Publikationsliste Dr. Tobias Hutzenlaub

• Originalarbeiten in wissenschaftlichen Fachzeitschriften
• Reviews/Übersichtsartikel in wissenschaftlichen Fachzeitschriften
• Vorträge
• Konferenzbeiträge

Originalarbeiten in wissenschaftlichen Fachzeitschriften

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2023

• F. Schlenker, P. Juelg, J. Lüddecke, N. Paust, R. Zengerle, T. Hutzenlaub
  Nanobead handling on a centrifugal microfluidic LabDisk for automated extraction of cell-free circulating DNA with high recovery rates
  2023 Analyst

2021

• J.-N. Klatt, T.J. Dinh, O. Schilling, R. Zengerle, F. Schmidt, T. Hutzenlaub, N. Paust
  Automation of peptide desalting for proteomic liquid chromatography–tandem mass spectrometry by centrifugal microfluidics
  2021 Lab on a Chip, Band: 21, Nummer: 21, Seite: 2255
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  Kurzfassung

  For large-scale analysis of complex protein mixtures, liquid chromatography – tandem mass spectrometry (LC-MS/MS) has been proven to be one of the most versatile tools due to its high sensitivity and ability to both identify and quantify thousands of proteins in a single measurement. Sample preparation typically comprises site-specific cleavage of proteins into peptides, followed by desalting and concomitant peptide enrichment, which is commonly performed by solid phase extraction. Desalting workflows may include multiple liquid handling steps and are thus error prone and labour intensive. To improve the reproducibility of sample preparation for low amounts of protein, we present a centrifugal microfluidic disk that automates all liquid handling steps required for peptide desalting by solid phase extraction (DesaltingDisk). Microfluidic implementation was enabled by a novel centrifugal microfluidic dosing on demand structure that enabled mapping multiple washing steps onto a microfluidic disk. Evaluation of the microfluidic disk was performed by LC-MS/MS analysis of tryptic HEK-293 eukaryotic cell peptide mixtures desalted either using the microfluidic disk or a manual workflow. A comparable number of peptides were identified in the disk and manual set with 19 775 and 20 212 identifications, respectively. For a core set of 10 444 peptides that could be quantified in all injections, intensity coefficients of variation were calculated based on label-free quantitation intensities. The disk set featured smaller variability with a median CV of 9.3% compared to the median CV of 12.6% for the manual approach. Intensity CVs on protein level were lowered from 5.8% to 4.2% when using the LabDisk. Interday reproducibility for both workflows was assessed by LC-SRM/MS analysis of samples that were spiked with 11 synthetic peptides of varying hydrophobicity. Except for the most hydrophilic and hydrophobic peptides, the average CV was lowered to 3.6% for the samples processed with the disk compared to 7.2% for the manual workflow. The presented centrifugal microfluidic DesaltingDisk demonstrates the potential to improve reproducibility in the sample preparation workflow for proteomic mass spectrometry, especially for application with limited amount of sample material.
• J.-N. Klatt, T. Hutzenlaub, T. Subkowski, T. Müller, S. Hennig, R. Zengerle, N. Paust
  Blocking Protein Adsorption in Microfluidic Chips by a Hydrophobin Coating
  2021 ACS Appl. Polym. Mater., Band: 3, Nummer: 7, Seiten: 3278 - 3286
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  Kurzfassung

  Microfluidics allows the miniaturization of biochemical analyses. Small dimensions reduce sample and reagent consumption and enhance reaction rates. A downside is that high surface-to-volume ratios increase the unspecific binding of proteins to the substrate material. The resulting sample loss and reagent depletion decrease the sensitivity and specificity of protein-based assays, especially if low concentrations are analyzed. Here, we introduce the hydrophobin coating of microfluidic chips made of cyclic olefin copolymers (COC). The recombinant hydrophobin H*Protein B self-assembles into stable monolayers on hydrophobic surfaces, making them hydrophilic and thus reducing hydrophobic interactions between the chip surfaces and proteins. The substrate and sealing layers of the microfluidic chip were simply dip-coated and subsequently assembled by thermodiffusion bonding, which renders our coating procedure compatible with mass fabrication. Contact angle measurements and atomic force microscopy were used to evaluate the effect of high temperatures (107 °C) on COC substrates coated with H*Protein B. The efficiency of the protein-repellent coating was evaluated by depletion experiments with bovine serum albumin, human serum, and cerebrospinal fluid in microfluidic chips. Protein recovery was investigated down to protein concentrations of 0.3 μg/mL. Recoveries of 90% were observed with total protein amounts of 10 ng, even for microfluidic channels up to 835 mm in length and with a cross section of 80 μm × 230 μm in a COC 6013/8007 foil. For comparison, only 30 and 60% of the protein was recovered in uncoated microfluidic channels with lengths of 835 and 128 mm, respectively. The long-term stability of the hydrophobin-coated chips for 8 weeks was demonstrated.
• F. Schlenker, E. Kipf, N. Borst, N. Paust, R. Zengerle, F. von Stetten, P. Juelg, T. Hutzenlaub
  Centrifugal Microfluidic Integration of 4-Plex ddPCR Demonstrated by the Quantification of Cancer-Associated Point Mutations
  2021 Processes, Band: 2021, Nummer: 9, Ergänzungsband: 97
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  Kurzfassung

  We present the centrifugal microfluidic implementation of a four-plex digital droplet polymerase chain reaction (ddPCR). The platform features 12 identical ddPCR units on a LabDisk cartridge, each capable of generating droplets with a diameter of 82.7 +/- 9 µm. By investigating different oil–surfactant concentrations, we identified a robust process for droplet generation and stabilization. We observed high droplet stability during thermocycling and endpoint fluorescence imaging, as is required for ddPCRs. Furthermore, we introduce an automated process for fourcolor fluorescence imaging using a commercial cell analysis microscope, including a customized software pipeline for ddPCR image evaluation. The applicability of ddPCRs is demonstrated by the quantification of three cancer-associated KRAS point mutations (G12D, G12V and G12A) in a diagnostically relevant wild type DNA background. The four-plex assay showed high sensitivity (3.5–35 mutant DNA copies in 15,000 wild type DNA copies) and linear performance (R2 = 0.99) across all targets in the LabDisk.
• D. Kainz, B. Breiner, S. M. Früh, T. Hutzenlaub, R. Zengerle, N. Paust
  Eliminating viscosity bias in lateral flow tests
  2021 Microsystems & Nanoengineering, Band: 7, Seite: 72
• J.-N. Klatt, I. Schwarz, T. Hutzenlaub, R. Zengerle, F. Schwemmer, D. Kosse, J. Vincent, M. Scaer, K. Franaszczuk, D. Wadsworth, N. Paust
  Miniaturization, Parallelization, and Automation of Endotoxin Detection by Centrifugal Microfluidics
  2021 Analytical Chemistry, Band: 93, Nummer: 24
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  Kurzfassung

  We demonstrate microfluidic automation and parallelization of Limulus amebocyte lysate (LAL)-based bacterial endotoxin testing using centrifugal microfluidics. LAL is the standard reagent to test for endotoxin contaminations in injectable pharmaceuticals. The main features of the introduced system are more than 90% reduction of LAL consumption, from 100 μL/reaction to 9.6 μL/reaction, automated liquid handling to reduce opportunities for contamination and manual handling errors, and microfluidic parallelization by integrating 104 reactions into a single centrifugal microplate. In a single Eclipse microplate, 21 samples and their positive product controls are tested in duplicate. In addition, a standard curve with up to five points is generated, resulting in a total of 104 reactions. Test samples with a defined concentration of 0.5 endotoxin units per milliliter were tested, resulting in a coefficient of variation below 0.75%. A key feature for achieving a small coefficient of variation is ensuring the same path length along the microfluidic channels to the final reaction chambers for each sample and the reagent, so that any unspecific adsorption to the polymer surfaces does not affect the accuracy and precision. Analysis of a sample containing naturally occurring endotoxin with the developed microfluidic microplate yielded comparable results to the conventional testing method. A test with eight commercially available pharmaceuticals was found to pass all requirements for bacterial endotoxin testing as specified in the United States Pharmacopeia. The automated endotoxin testing system reveals specific advantages of centrifugal microfluidics for analytical biochemistry applications. Small liquid volumes are handled (metered, mixed, and aliquoted) in a very precise, highly integrated, and highly parallel manner within mass-fabricated microplates.
• L. Becherer, J. F. Hess, S. Frischmann, M. Bakheit, H. Nitschko, S. Stinco, F. Zitz, H. Hofer, G. Porro, F. Hausladen, K. Stock, D. Drossart, H. Wurm, H. Kuhn, D. Huber, T. Hutzenlaub, N. Paust, M. Keller, O. Strohmeier, S. Wadle, N. Borst, R. Zengerle, F. von Stetten
  Point-of-Care System for HTLV-1 Proviral Load Quantification by Digital Mediator Displacement LAMP
  2021 Micromachines, Band: 12, Nummer: 2, Seite: 159
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  Kurzfassung

  This paper presents a universal point-of-care system for fully automated quantification of human T-cell lymphotropic virus type 1 (HTLV-1) proviral load, including genomic RNA, based on digital reverse RNA transcription and c-DNA amplification by MD LAMP (mediator displacement loop-mediated isothermal amplification). A disposable microfluidic LabDisk with pre-stored reagents performs automated nucleic acid extraction, reaction setup, emulsification, reverse transcription, digital DNA amplification, and quantitative fluorogenic endpoint detection with universal reporter molecules. Automated nucleic acid extraction from a suspension of HTLV-1-infected CD4+ Tlymphocytes (MT-2 cells) yielded 8 +/- 7 viral nucleic acid copies per MT-2 cell, very similar to the manual reference extraction (7 +/- 2 nucleic acid copies). Fully automated sample processing from whole blood spiked with MT-2 cells showed a comparable result of 7 +/- 3 copies per MT-2 cell after a run time of two hours and 10 min.
• F. Schlenker, E. Kipf, M. Deuter, I. Höffkes, M. Lehnert, R. Zengerle, F von Stetten, F. Scherer, J. Wehrle, N. von Bubnoff, P. Juelg, T. Hutzenlaub, N. Borst
  Stringent Base Specific and Optimization-Free Multiplex Mediator Probe ddPCR for the Quantification of Point Mutations in Circulating Tumor DNA
  2021 cancers, Band: 13, Nummer: 22, Seite: 5742
• P. Juelg, E. Kipf, M. Specht, M. Fillies, C. Eckert, N. Paust, R. Zengerle, M. Lehnert, T. Hutzenlaub
  The MRD disk: automated minimal residual disease monitoring by highly sensitive centrifugal microfluidic multiplex qPCR
  2021 Lab Chip, Band: 21, Seiten: 558 - 570
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  Kurzfassung

  We present a proof-of-principle study on automated, highly sensitive and multiplexed qPCR quantification by centrifugal microfluidics. The MRD disk can be used for standardisation of repetitive, longitudinal assays with high requirements on reproducibility and sensitivity, such as cancer monitoring. In contrast to high-throughput qPCR automation by bulky and expensive robotic workstations we employ a small centrifugal microfluidic instrument, addressing the need of low- to mid-throughput applications. As a potential application we demonstrate automated minimum residual disease (MRD) monitoring of prognostic markers in patients with acute lymphoblastic leukaemia (ALL). The disk-workflow covers all aspects of clinical gold standard MRD quantification: generation of standard curves, specificity controls, no template controls and quantification of the ALL patient sample. We integrated a highly sensitive, colorimetric 2-plex analysis of MRD targets, as well as a 2-plex analysis of reference genes, both in parallel and in a single LabDisk cartridge. For this purpose, a systematic procedure for crosstalk- and signal-to-noise-optimisation is introduced, providing a guideline for efficient multiplex readout inside microfluidic platforms. The qPCR standard curves (n = 12/12) generated on-disk reach clinically required linearity (R2 = 98.1% to R2 = 99.8%). In three consecutive MRD disk runs with an ALL patient sample containing the two representative MRD targets VH3D3D5JH3 and VkIkde, we observe high accordance between the on-disk quantifications (48 ± 6 copies/reaction and 69 ± 6 copies/reaction) and the expected concentrations (57 copies/reaction for both targets). In comparison to the clinical gold standard of manually pipetted, singleplex assays, the MRD disk yields comparable limit of quantification (1 × 10−4) in n = 6/6 analyses (vs. n = 4/4 in gold standard) and a limit of detection (1 × 10−5) in n = 6/6 analysis (vs. n = 2/4 in gold standard). The automation reduces the risk of manual liquid handling errors, making the MRD disk an attractive solution to assure reproducibility in moderate-throughput, longitudinal gene quantification applications.
• M. Tsagiopoulou, M. C. Maniou, N. Pechlivanis, A. Togkousidis, M. Kotrová, T. Hutzenlaub, I. Kappas, A. Chatzidimitriou, F. Psomopoulos
  UMIc: A Preprocessing Method for UMI Deduplication and Reads Correction
  2021 Front. Genet., Band: May, 28
• F. Schlenker, E. Kipf, N. Borst, T. Hutzenlaub, R. Zengerle, F. von Stetten, P. Juelg
  Virtual Fluorescence Color Channels by Selective Photobleaching in Digital PCR Applied to the Quantification of KRAS Point Mutations
  2021 Analytical Chemistry, Band: 93, Nummer: 30, Seiten: 10538 - 10545
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  Kurzfassung

  Multiplexing of analyses is essential to reduce sample and reagent consumption in applications with large target panels. In applications such as cancer diagnostics, the required degree of multiplexing often exceeds the number of available fluorescence channels in polymerase chain reaction (PCR) devices. The combination of photobleaching-sensitive and photobleaching-resistant fluorophores of the same color can boost the degree of multiplexing by a factor of 2 per channel. The only additional hardware required to create virtual fluorescence color channels is a low-cost light-emitting diode (LED) setup for selective photobleaching. Here, we present an assay concept for fluorescence color multiplexing in up to 10 channels (five standard channels plus five virtual channels) using the mediator probe PCR with universal reporter (UR) fluorogenic oligonucleotides. We evaluate the photobleaching characteristic of 21 URs, which cover the whole spectral range from blue to crimson. This comprehensive UR data set is employed to demonstrate the use of three virtual channels in addition to the three standard channels of a commercial dPCR device (blue, green, and red) targeting cancer-associated point mutations (KRAS G12D and G12V). Moreover, a LOD (limit of detection) analysis of this assay confirms the high sensitivity of the multiplexing method (KRAS G12D: 16 DNA copies/reaction in the standard red channel and KRAS G12V: nine DNA copies/reaction in the virtual red channel). Based on the presented data set, optimal fluorogenic reporter combinations can be easily selected for the application-specific creation of virtual channels, enabling a high degree of multiplexing at low optical and technical effort.

2020

• J. F. Hess, M. Kotrová, S. Calabrese, N. Darzentas, T. Hutzenlaub, R. Zengerle, M. Brüggemann, N. Paust
  Automation of amplicon-based library preparation for next generation sequencing by centrifugal microfluidics
  2020 Anal Chem, Band: 92, Nummer: 19, Seiten: 12833 - 12841
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  Kurzfassung

  Next generation sequencing has become a mainstream method in bioanalysis. Improvements in sequencing and bioinformatics turned the complex and cumbersome library preparation to the bottle neck in terms of reproducibility and costs in the complete NGS workflow. Here, we introduce an automated library preparation approach based on a generic centrifugal microfluidic car-tridge. Multiplex polymerase chain reaction amplification and subsequent clean-up were processed with all reagents pre-stored on disk, including cell line-based DNA as quality control. Exchange of pre-stored reagents allows to apply the cartridge to different target genes. Sequencing of automatically prepared libraries from T-cell receptor and immunoglobulin gene rearrangements in context of lymphoproliferative disorders demonstrated excellent clean-up performance between 91.9% and 99.9% of target DNA reads and successful amplification of all target regions by up to 15 forward combined with four reverse primers. The fully auto-mated library preparation by centrifugal microfluidics thus offers attractive automation options in diagnostic settings.
• J.-N. Klatt, M. Depke, N. Goswami, N. Paust, R. Zengerle, F. Schmidt, T. Hutzenlaub
  Tryptic digestion of human serum for proteomic mass spectrometry automated by centrifugal microfluidics
  2020 Lab Chip, Band: 20, Seite: 2937
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  Kurzfassung

  Mass spectrometry has become an important analytical tool for protein research studies to identify, characterise and quantify proteins with unmatched sensitivity in a highly parallel manner. When transferred into clinical routine, the cumbersome and error-prone sample preparation workflows present a major bottleneck. In this work, we demonstrate tryptic digestion of human serum that is fully automated by centrifugal microfluidics. The automated workflow comprises denaturation, digestion and acidification. The input sample volume is 1.3 μl only. A triplicate of human serum was digested with the developed microfluidic chip as well as with a manual reference workflow on three consecutive days to assess the performance of our system. After desalting and liquid chromatography tandem mass spectrometry, a total of 604 proteins were identified in the samples digested with the microfluidic chip and 602 proteins with the reference workflow. Protein quantitation was performed using the Hi3 method, yielding a 7.6% lower median intensity CV for automatically digested samples compared to samples digested with the reference workflow. Additionally, 17% more proteins were quantitated with less than 30% CV in the samples from the microfluidic chip, compared to the manual control samples. This improvement can be attributed to the accurate liquid metering with all volume CVs below 1.5% on the microfluidic chip. The presented automation solution is attractive for laboratories in need of robust automation of sample preparation from small volumes as well as for labs with a low or medium throughput that does not allow for large investments in robotic systems.

2019

• P. Juelg, M. Specht, E. Kipf, M. Lehnert, C. Eckert, M. Keller, T. Hutzenlaub, F. von Stetten, R. Zengerle, N. Paust
  Automated serial dilutions for high-dynamic-range assays enabled by fill-level-coupled valving in centrifugal microfluidics
  2019 Lab Chip, Band: 19, Seiten: 2205 - 2219
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  Kurzfassung

  We introduce a new concept for centrifugal microfluidics that enables fully automated serial dilution generation without any additional means besides temperature control. Key feature is time-independent, serial valving of mixing chambers by fill-level-coupled temperature change rate (FLC-TCR) actuated valving. The automated dilution is realized under continuous rotation which enables reliable control of wetting liquids without the need of any additional fabrication steps such as hydrophobic coatings. All fluidic features are implemented in a monolithic fashion and disks are manufactured by foil thermoforming for scalable manufacturing. The new valving concept is demonstrated to reliably prevent valving if the diluted sample is not added to the mixing chamber (n = 30) and ensures valving if the dilution stage is completed (n = 15). Accuracy and precision of the automated serial dilution are verified by on-disk generation of qPCR standard curve dilutions and compared with manually generated reference dilutions. In a first step, the 5-log-stages standard curves are evaluated in a commercial qPCR thermocycler revealing a linearity of R² ≥ 99.92 % for the proposed LabDisk method vs. R² ≥ 99.67 % in manual reference dilutions. In a second step, the disk automated serial dilution is combined with on-disk qPCR thermocycling and readout, both inside a LabDisk Player. A 4-log-stages linearity of R² ≥ 99.81 % and a sensitivity of one leukemia associated ETV6-RUNX1 mutant DNA copy in a background of 100,000 wild-type DNA copies is achieved.
• D. Kainz, S. M. Früh, T. Hutzenlaub, R. Zengerle, N. Paust
  Flow control for lateral flow strips with centrifugal microfluidics
  2019 Lab Chip, Seiten: 2718 - 2727
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  Kurzfassung

  Lateral flow strips (LFSs) are widely used for clinical diagnostics. The restricted flow control of the current designs is one challenge to the development of quantitative and highly sensitive LFSs. Here, we present a flow control for LFSs using centrifugal microfluidics. In contrast to previously presented implementations of lateral flow membranes into centrifugal microfluidic cartridges, we direct the flow radially outwards through the membrane. We control the flow using only the centrifugal force, thus it is independent of membrane wetting properties and permeability. The flow rate can be decreased and increased, enabling control of incubation times for a wide variety of samples. We deduced a formula as a guideline for the integration of chromatographic membranes into centrifugal microfluidic disks to ensure that all the sample liquid flows through the membrane, hence safely avoiding bypass flow around the membrane. We verified the calculated operation conditions using different membranes, different flow rates, and different sample viscosities.

2016

• F. Stumpf, F. Schwemmer, T. Hutzenlaub, D. Baumann, O. Strohmeier, G. Dingemanns, G. Simons, C. Sager, L. Plobner, F. von Stetten, R. Zengerle, D. Mark
  LabDisk with complete reagent prestorage for sample-to-answer nucleic acid based detection of respiratory pathogens verified with influenza A H3N2 virus
  2016 Lab Chip, Band: 16, Seiten: 199 - 207
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  Kurzfassung

  Portable point-of-care devices for pathogen detection require easy, minimal and user-friendly handling steps and need to have the same diagnostic performance compared to centralized laboratories. In this work we present a fully automated sample-to-answer detection of influenza A H3N2 virus in a centrifugal LabDisk with complete prestorage of reagents. Thus, the initial supply of the sample remains the only manual handling step. The self-contained LabDisk automates by centrifugal microfluidics all necessary process chains for PCR-based pathogen detection: pathogen lysis, magnetic bead based nucleic acid extraction, aliquoting of the eluate into 8 reaction cavities, and real-time reverse transcription polymerase chain reaction (RT-PCR). Prestored reagents comprise air dried specific primers and fluorescence probes, lyophilized RT-PCR mastermix and stick-packaged liquid reagents for nucleic acid extraction. Employing two different release frequencies for the stick-packaged liquid reagents enables on-demand release of highly wetting extraction buffers, such as sequential release of lysis and binding buffer. Microfluidic process-flow was successful in 54 out of 55 tested LabDisks. We demonstrate successful detection of the respiratory pathogen influenza A H3N2 virus in a total of 18 LabDisks with sample concentrations down to 2.39 × 104 viral RNA copies per ml, which is in the range of clinical relevance. Furthermore, we detected RNA bacteriophage MS2 acting as internal control in 3 LabDisks with a sample concentration down to 75 plaque forming units (pfu) per ml. All experiments were applied in a 2 kg portable, laptop controlled point-of-care device. The turnaround time of the complete analysis from sample-to-answer was less than 3.5 hours.
• I. Schwarz, S. Zehnle, T. Hutzenlaub, R. Zengerle, N. Paust
  System-level network simulation for robust centrifugal-microfluidic lab-on-a-chip systems
  2016 Lab Chip, Band: 16, Seiten: 1873 - 1885
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  Kurzfassung

  Centrifugal microfluidics shows a clear trend towards a higher degree of integration and parallelization1. This trend leads to an increase in number and density of integrated microfluidic unit operations. The fact that all unit operations are processed by the same common spin protocol turns higher integration into higher complexity. To allow for efficient development anyhow, we introduce advanced lumped models for network simulations in centrifugal microfluidics. These models consider the interplay of centrifugal and Euler pressures, viscous dissipation, capillary pressures and pneumatic pressures. The simulations are fast and simple to set up and allow for the precise prediction of flow rates as well as switching and valving events. During development, channel and chamber geometry variations due to manufacturing tolerances can be taken into account as well as pipetting errors, variations of contact angles, compliant chamber walls and temperature variations in the processing device. As an example for considering these parameters during development, we demonstrate simulation based robustness analysis for pneumatic siphon valving in centrifugal microfluidics. Subsequently the influence of liquid properties on pumping and valving is studied for four liquids relevant for biochemical analysis, namely: water (large surface tension), blood plasma (large contact angle hysteresis), ethanol/water (highly wetting) and glycerine/water (highly viscous). In a second example, we derive a spin protocol to attain a constant flow rate under varying pressure conditions. Both examples show excellent agreement to experimental validations.

2015

• F. Schwemmer, T. Hutzenlaub, D. Buselmeier, N. Paust, F. von Stetten, D. Mark, R. Zengerle, D. Kosse
  Centrifugo-pneumatic multi-liquid aliquoting – parallel aliquoting and combination of multiple liquids in centrifugal microfluidics
  2015 Lab Chip, Band: 15, Seiten: 3250 - 3258
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  Kurzfassung

  The generation of mixtures with precisely metered volumes is essential for reproducible automation of laboratory workflows. Splitting a given liquid into well-defined metered sub-volumes, the so-called aliquoting, has been frequently demonstrated on centrifugal microfluidics. However, so far no solution exists for assays that require simultaneous aliquoting of multiple, different liquids and the subsequent pairwise combination of aliquots with full fluidic separation before combination. Here, we introduce the centrifugo-pneumatic multi-liquid aliquoting designed for parallel aliquoting and pairwise combination of multiple liquids. All pumping and aliquoting steps are based on a combination of centrifugal forces and pneumatic forces. The pneumatic forces are thereby provided intrinsically by centrifugal transport of the assay liquids into dead end chambers to compress the enclosed air. As an example, we demonstrate simultaneous aliquoting of 1.) a common assay reagent into twenty 5 µl aliquots and 2.) five different sample liquids, each into four aliquots of 5 µl. Subsequently, the reagent and sample aliquots are simultaneously transported and combined into twenty collection chambers. All coefficients of variation for metered volumes were between 0.4% - 1.0% for intra-run variations and 0.5% - 1.2% for inter-run variations. The aliquoting structure is compatible to common assay reagents with a wide range of liquid and material properties, demonstrated here for contact angles between 20° and 60°, densities between 789 and 1855 kg / m3 and viscosities between 0.89 and 4.1 mPa s. The centrifugo-pneumatic multi-liquid aliquoting is implemented as a passive fluidic structure into a single fluidic layer. Fabrication is compatible to scalable fabrication technologies such as injection molding or thermoforming and does not require any additional fabrication steps such as hydrophilic or hydrophobic coatings or integration of active valves.

2014

• L. Zielke, T. Hutzenlaub, D. R. Wheeler, I. Manke, T. Arlt, N. Paust, R. Zengerle, S. Thiele
  A Combination of X-Ray Tomography and Carbon Binder Modeling: Reconstructing the Three Phases of LiCoO2 Li-Ion Battery Cathodes
  2014 Adv Energy Mater, Band: 4, Seite: 1301617
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  Kurzfassung

  X-ray tomography allows the active-material domain (LiCoO2) of Li-ion battery cathodes to be imaged, but it is unable to resolve the carbon-binder domain (CBD). Here, a new method for creating a complete 3D representation (virtual design) of all three phases of a cathode is provided; this includes the active-material domain, the CBD, and the electrolyte-filled pore space. It combines X-ray tomographic data of active material with a statistically modeled CBD. Two different statistical CBD morphology models are compared as examples: i) a random cluster model representing a standard mixture of carbon black and polyvenylidene fluoride (PVDF) and ii) a fiber model. The transport parameters are compared in a charged and a discharged cathode. The results demonstrate that the CBD content and morphology changes the ionic and electronic transport parameters dramatically and thus cannot be neglected. Calculations yield that the fiber model shows up to three times higher electrical conductivity at the same CBD content (discharged case) and better ionic diffusion conditions for all CBD contents. In the charged case, the morphology impact on electrical conduction is small. This effective method to generate transport parameters for different CBDs can be transferred to other CBD morphologies and electrodes.
• L. Zielke, T. Hutzenlaub, D. R. Wheeler, C.-W. Chao, I. Manke, A. Hilger, N. Paust, R. Zengerle, S. Thiele
  Three-Phase Multiscale Modeling of a LiCoO 2 Cathode: Combining the Advantages of FIB–SEM Imaging and X-Ray Tomography
  2014 Adv Energy Mater, Band: 5, Seite: 1401612
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  Kurzfassung

  LiCoO 2 electrodes contain three phases, or domains, each having specific-intended functions: ion-conducting pore space, lithium-ion-reacting active material, and electron conducting carbon-binder domain (CBD). Transport processes take place in all domains on different characteristic length scales: from the micrometer scale in the active material grains through to the nanopores in the carbon-binder phase. Consequently, more than one imaging approach must be utilized to obtain a hierarchical geometric representation of the electrode. An approach incorporating information from the micro- and nanoscale to calculate 3D transport-relevant properties in a largereconstructed active domain is presented. Advantages of focused ion beam/ scanning electron microscopy imaging and X-ray tomography combined by a spatial stochastic model, validated with an artifi cially produced reference structure are used. This novel approach leads to signifi cantly different transport relevant properties compared with previous tomographic approaches: nanoporosity of the CBD leads to up to 42% additional contact area between active material and pore space and increases ionic conduction by a factor of up to 3.6. The results show that nanoporosity within the CBD cannot be neglected.
• T. Hutzenlaub, S. Thiele, N. Paust, R. Spotnitz, R. Zengerle, C. Walchshofer
  Three-dimensional electrochemical Li-ion battery modelling featuring a focused ion-beam/scanning electron microscopy based three-phase reconstruction of a LiCoO2 cathode
  2014 Electrochim Acta, Band: 115, Seiten: 131 - 139
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  Kurzfassung

  We combine a three-phase, three-dimensional reconstruction of a LiCoO2battery cathode based onfocused ion-beam/scanning electron microscopy (FIB/SEM) imaging with an electrochemical model. Themodel considers the electric potential and lithium/salt concentration distribution in both the liquid elec-trolyte and the solid active-material phases. In contrast to previously presented models, we spatiallyresolve the carbon-binder phase to provide a more realistic description of the electric potential. Weobserve that carbon-binder coverage of the solid electrolyte interface (SEI) impedes local surface reac-tions and thus affects lithium redistribution. For the considered cathode, the total surface to volumeratio of the SEI is reduced from 11.2 × 105to 6.5 × 105m2m−3when the carbon-binder phase is modelledexplicitly. This leads to increased inhomogeneity of the lithium concentration in active-material grainsduring charging.Additionally, we study lithium/salt concentration in the electrolyte, revealing gradients between 0.9and 1.5 kmol m−3depending on the distance to the separator. This is significant because the lithium/saltconcentration directly affects the ion transport properties of the electrolyte.

2013

• T. Hutzenlaub, A. Asthana, J. Becker, R. Wheeler, R. Zengerle, S. Thiele
  FIB/SEM-based calculation of tortuosity in a porous LiCoO2 cathode for a Li-ion battery
  2013 Electrochem Commun, Band: 27, Seiten: 77 - 80
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  Kurzfassung

  We present a new method to quantify tortuosity in the porous, LiCoO2 cathode of a Li-ion battery. The starting point is a previously published 3D reconstruction from FIB/SEM images with three phases, the active material domain, carbon-binder domain and pore space. Based on this geometrical configuration, we compute effective diffusivities, from which we in turn derive tortuosity values for the pore space ranging between 5 and 11.6 for the three spatial directions. In a next step, we compare our approach to an imaging method that employs back-filling material. These methods do not differentiate between the carbon-binder domain and the pore space. Thus we remove the carbon-binder domain from our 3D reconstruction and add its volume to the pore space. As a result of this procedure, the tortuosity is greatly reduced to values between 1.5 and 1.9. Experiments suggest that both results for tortuosity are inaccurate and that the real values lie somewhere between these parameter sets. Hence, based on experimental data, we propose a nanoporous carbon-binder domain and derive intermediate tortuosity values between 4.2 and 6.1. These values are consistent with experimental values for similar Li-ion cathodes reported previously.
• T. Hutzenlaub, J. Becker, R. Zengerle, S. Thiele
  How Coarsening the 3D Reconstruction of a Porous Material Influences Diffusivity and Conductivity Values
  2013 ECS Electrochemistry Letters, Band: 2, Seiten: F14 - F17
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  Kurzfassung

  Coarsening the resolution of a 3D reconstruction is a common approach to make simulations feasible with regard to computational resources. We coarsen the reconstruction of a PEMFC cathode catalyst layer and investigate how this influences parameters such as diffusivity and conductivity. This is also an indication of how trustworthy these parameters are in the first place, because imaging itself is a coarsened representation of the real morphology. While diffusivity remains approximately constant due to the opposing behavior of bulk and Knudsen diffusivity, conductivity is strongly affected. The method introduced here is transferable to evaluate 3D reconstructions of other porous materials.
• T. Hutzenlaub, J. Becker, R. Zengerle, S. Thiele
  Modelling the water distribution within a hydrophilic and hydrophobic 3D reconstructed cathode catalyst layer of a proton exchange membrane fuel cell
  2013 J Power Sources, Band: 227, Seiten: 260 - 266
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  Kurzfassung

  We reconstruct a section of the cathode catalyst layer (CCL) of a Gore PEMFC membrane electrode assembly three-dimensionally with nanometre scale resolution. Subsequently, we present a new modelling method to fill the pore space of this matrix stepwise with water, enabling the description of varying saturation conditions of the CCL. The method is based on a 3D pore size distribution and enables to differentiate between a hydrophilic and a hydrophobic CCL. It utilizes a sequence to fill the pores according to their size, going from small to large (hydrophilic) or vice versa (hydrophobic), until a predefined value of water saturation is reached. We compare both cases by calculating an effective diffusivity for oxygen in nitrogen in all spatial directions. Both the hydrophilic and the hydrophobic case display a similar ability to transport oxygen up to approximately 50% water saturation of the pore space. At higher water saturation, we calculate larger diffusivity values for the hydrophobic case. Finally, we calculate the specific reaction surface area that is accessible from the gas diffusion layer via unfilled pores for all water saturation conditions. At 50% saturation, the hydrophobic case displays a twenty times larger reaction surface area than the hydrophilic case.
• S. Thiele, T. Fürstenhaupt, D. Banham, T. Hutzenlaub, V. Birss, C. Ziegler, R. Zengerle
  Multiscale tomography of nanoporous carbon-supported noble metal catalyst layers
  2013 J Power Sources, Band: 228, Seiten: 185 - 192
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  Kurzfassung

  Noble metal catalysts are a scarce, non-renewable resource, and yet are required in a wide range of industrial applications, including in polymer electrolyte membrane fuel cells (PEMFCs). The effectiveness of PEMFCs depends not only on the size, active surface area, and distribution of the Pt catalyst nanoparticles, which affects reaction kinetics, but also on the porous structure of the carbon support, which affects mass transport. Unfortunately, the very different size scales – several nm for the Pt catalyst vs. several μm for the porosity features – cannot be characterized by a single method. Here, we present a novel approach for integrating information from both of these size scales to build a single geometrical model. Focused Ion Beam – Scanning Electron Microscope tomography (SEMt) was carried out on a commercial PEMFC cathode catalyst layer to characterize porosity, connectivity as well as pore-size and grain-size distribution. Transmission Electron Microscopy tomography (TEMt) was used to analyze volume and surface area distributions of nanometer sized platinum catalyst particles. Further, we propose an up-scaling approach to translate the information obtained from TEMt to SEMt. Knowledge of catalyst particle locations within the solid support matrix will be critical in enabling the analysis of limiting transport processes in PEMFC CCLs.

2012

• T. Hutzenlaub, S. Thiele, R. Zengerle, C. Ziegler
  Three-Dimensional Reconstruction of a LiCoO2 Li-Ion Battery Cathode
  2012 Electrochem Solid St, Band: 15, Nummer: 3, Seiten: A33 - A36
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  Kurzfassung

  In the reported work, we reconstruct a LiCoO2 cathode three-dimensionally, for the first time differentiating between all three constituents: (i) active material, (ii) binder and (iii) pore space for this specific material. We apply a hybrid method of manual and grey-scale threshold segmentation to reconstruct a cuboid with a volume of approximately 4500 µm3. The reconstructed geometry is characterised to support the data basis of homogenized cathode models. We solve numerically for electrical conductivity and derive electrical tortuosity analytically from the result. Pore space connectivity and pore size distribution are also calculated. The segmented images are provided as supplementary electronic material.

2011

• T. Hutzenlaub, N. Paust, R. Zengerle, C. Ziegler
  The effect of wetting properties on bubble dynamics and fuel distribution in the flow field of direct methanol fuel cells
  2011 J Power Sources, Band: 196, Seiten: 8048 - 8056
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  Kurzfassung

  We investigate CO2 bubble dynamics on the anode side of a direct methanol fuel cell (DMFC). In contrast to previous studies, we analyse the effect of both channel wall and diffusion layer wettability by observing two-phase flow from the side at different mean velocities of the fuel supply. Hydrophobic and hydrophilic flow channel surfaces are compared experimentally. The hydrophilic flow channel leads to a minimum pressure drop along the channel. Bubbles show virtually no pinning and consequently travel at approximately the mean fuel velocity inside the channel. In contrast to this, we observe bubble pinning in the hydrophobic flow channels. The critical fuel velocities necessary for detachment of the bubbles mainly depends on bubble length. We identify and describe a new bubble bypass configuration where fuel bypass channels are solely generated in a favourable position underneath a blocking bubble along the diffusion layer. This enforces fuel to bypass the CO2 bubble at a large relative velocity close to the diffusion layer, thus enhancing mass transfer. Our experimental findings are in excellent agreement with a CFD/analytical model. This model allows for quantitative prediction of average bypass flow velocity.

Reviews/Übersichtsartikel in wissenschaftlichen Fachzeitschriften

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2020

• J. F. Hess, T.A. Kohl, M. Kotrová, K. Roensch, T. Paprotka, V. Mohr, T. Hutzenlaub, M. Brüggemann, R. Zengerle, S. Niemann, N. Paust
  Library preparation for next generation sequencing: A review of automation strategies
  2020 Biotechnol Adv, Seite: 107537
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  Kurzfassung

  Next generation sequencing is in the process of evolving from a technology used for research purposes to one which is applied in clinical diagnostics. Recently introduced high throughput and benchtop instruments offer fully automated sequencing runs at a lower cost per base and faster assay times. In turn, the complex and cumbersome library preparation, starting with isolated nucleic acids and resulting in amplified and barcoded DNA with sequencing adapters, has been identified as a significant bottleneck. Library preparation protocols usually consist of a multistep process and require costly reagents and substantial hands-on-time. Considerable emphasis will need to be placed on standardisation to ensure robustness and reproducibility. This review presents an overview of the current state of automation of library preparation for next generation sequencing. Major challenges associated with library preparation are outlined and different automation strategies are classified according to their functional principle. Pipetting workstations allow high-throughput processing yet offer limited flexibility, whereas microfluidic solutions offer great potential due to miniaturisation and decreased investment costs. For the emerging field of single cell transcriptomics for example, microfluidics enable singularisation of tens of thousands of cells in nanolitre droplets and barcoding of the RNA to assign each nucleic acid sequence to its cell of origin. Finally, two applications, the characterisation of bacterial pathogens and the sequencing within human immunogenetics, are outlined and benefits of automation are discussed.

2019

• J. F. Hess, S. Zehnle, P. Juelg, T. Hutzenlaub, R. Zengerle, N. Paust
  Review on pneumatic operations in centrifugal microfluidics
  2019 Lab Chip, Band: 22, Seiten: 3745 - 3770
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  Kurzfassung

  Centrifugal microfluidics allows for miniaturization, automation and parallelization of laboratory workflows. The fact that centrifugal forces are always directed radially outwards has been considered a main drawback for the implementation of complex workflows leading to the requirement of additional actuation forces for pumping, valving and switching. In this work, we review and discuss the combination of centrifugal with pneumatic forces which enables transport of even complex liquids in any direction on centrifugal systems, provides actuation for valving and switching, offers alternatives for mixing and enables accurate and precise metering and aliquoting. In addition, pneumatics can be employed for timing to carry out any of the above listed unit operations in a sequential and cascaded manner. Firstly, different methods to generate pneumatic pressures are discussed. Then, unit operations and applications that employ pneumatics are reviewed. Finally, a tutorial section discusses two examples to provide insight into the design process. The first tutorial explains a comparatively simple implementation of a pneumatic siphon valve and provides a workflow to derive optimum design parameters. The second tutorial discusses cascaded pneumatic operations consisting of temperature change rate actuated valving and subsequent pneumatic pumping. In conclusion, combining pneumatic actuation with centrifugal microfluidics allows for the design of robust fluidic networks with simple fluidic structures that are implemented in a monolithic fashion. No coatings are required and the overall demands on manufacturing are comparatively low. We see the combination of centrifugal forces with pneumatic actuation as a key enabling technology to facilitate compact and robust automation of biochemical analysis.

Vorträge

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2024

• E. Kipf, P. Jülg, F. Schlenker, M. Fillies, C. Kranig, M. Specht, S. Groeneveld-Krentz, S. Neumann, R. Zengerle, F. von Stetten, N. Borst, R. Kirschner-Schwabe, T. Hutzenlaub, M. Lehnert, C. Eckert
  Messung des individuellen Therapieansprechens von akuten lymphoblastischen Leukämien (IRMA-4-ALL)
  2024 Translationale Forschung in der Personalisierten Medizin – Chancen und Hürden, Netzwerkveranstaltung für geförderte Projekte der „Innovationen für die individualisierte Medizin“ und der „Translationsp

2017

• F. Schuler, S. Wadle, N. Borst, M. Schulz, L. Becherer, J. Li, M. Specht, T. Hutzenlaub, N. Paust, R. Zengerle, F. von Stetten
  A Technology Platform for Digital Nucleic Acid Diagnostics at the Point of Care (invited talk)
  2017 3. Münchner point-of-care testing symposium, Deutsche Gesellschaft für Klinische Chemie und Laboratoriumsmedizin (DGKL), München, 13.-15. 3. 2017
• F. Schuler, N. Borst, S. Wadle, M. Schulz, M. Specht, J. Li, L. Becherer, T. Hutzenlaub, N. Paust, R. Zengerle, F. von Stetten
  Centrifugal Step Emulsification Allows Miniaturized Digital Droplet-RPA,-LAMP and -PCR on the Centrifugal Microfluidic Platform (invited talk)
  2017 9th Annual lab-on-a-chip & microfluidics Conference, Selectbio, Munich, 10.-11.5. 2017

Konferenzbeiträge

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2025

• J. Sum, T. Truong, C. Mikloska, M. Oberländer, N. von Bubnoff, L. Christiansen, S. Tornow, S. Derer, F. Janke, H. Sültmann, S. Zeissig, M. Linnebacher, C. Schafmayer, I. Nazarenko, F. Scherer, H. Becker, M. Kalweit, M. Lehnert, T. Hutzenlaub, R. Zengerle, N. Paust, P. Juelg
  Liquid Biopsy using Methylation Analysis-coupled digital PCR of Biomarkers to Detect Early-Onset Colorectal Cancer
  2025 Kongress "Prevention of eoCRC" HARMONIZE des OUTLIVE Verbundes, Lübeck, 24. – 26.03.2025
• C. Hensel, C. Kleber, J. N. Klatt, T. Hutzenlaub, F. von Stetten, J. C. Behrends, A. Schreiber
  Protein Sample Preparation for Nanopore Recording
  2025 Single Molecule Protein Sequencing (SMPS), Bolzano/Italy, January 18-24, 2025

2024

• T-T. Truong, Y. Kaku, J. Schlanderer, F. Schlenker, E. Kipf, E. Dazert, F. Axt, N. von Bubnoff, S. Kartmann, N. Borst, N. Paust, T. Hutzenlaub, P Juelg
  A robotic microfluidic approach for rapid sample-to-answer analysis of cell-free DNA
  2024 13th CNAPS International Symposium on Circulating Nucleic Acids in Plasma and Serum, Graz/Austria, 4-6 March 2024
• N. Klatt, M. Hinrichs, T. Hutzenlaub
  Centrifugal Microfluidic Automation of Proteomic Sample Preparation Techniques
  2024 40th International Symposium on Microscale Separations and Bioanalysis 2024 (MSB 2024), Brno/Czech Republic, 19-22 May 2024
• M. Neugebauer, S. Calabrese, A. Markl, L. Schumacher, T. Wolper, T-T. Truong, P. Juelg, N. Borst, T. Hutzenlaub, F. Scherer, F. von Stetten, M. Lehnert
  Increasing digital PCR performance in liquid biopsy using reporter emission multiplexing
  2024 13th CNAPS International Symposium on Circulating Nucleic Acids in Plasma and Serum, Graz/Austria, 4-6 March 2024
• J.F. Hess, J. Rüdiger, T. Hutzenlaub
  Microfluidic Automation of Library Preparation for Nanopore Sequencing
  2024 40th International Symposium on Microscale Separations and Bioanalysis 2024 (MSB 2024), Brno/Czech Republic, 19-22 May 2024

2023

• T.-T. Truong, K. Mikloska, N. Paust, T. Hutzenlaub, L. Kubetzko, S. Derer, N. von Bubnoff, P. Juelg
  Comparison of DNA reference material for pre analytics : Nucleosomal plasma spike ins reveal true recovery efficiencies of circulating cell free DNA extractions
  2023 ISMRC 2023 - 13th International Symposium on Minimal Residual Cancer, Hamburg, 02.-04.05.2023
• S. Murad, M. Heyer, F. Lickert, J. Menges, S. Calabrese, T. Hutzenlaub, N. Paust, P. Juelg
  Fast and bubble-free filling of nano-imprinted high-density picoliter well arrays for digital assays enabled by centrifugal microfluidics
  2023 MicroTAS 2023, Katovice/Poland, 15.-19.10.2023
• E. Mahmodi Arjmand, F. Schlenker, G. Grether, T. Tu Troung, T. Hutzenlaub, R. Zengerle, N. Paust, J. Lüddecke, P. Juelg
  Gleichzeitige Extraktion von extrazellulären Vesikeln und zellfreier DNA aus einer einzigen Blutprobe durch zentrifugale Mikrofluidik
  2023 Mikrosystemtechnik Kongress 2023, Dresden, 23.-25.10.2023
• C. Engelmann, C. Kleber, Y. Kaku, T.-T. Truong, N. Klatt, P. Jülg, T. Ensslen, P. Jain, J. Schwaiger, S. Kartmann, T. Hutzenlaub, A. Schreiber
  Protein Sample Preparation for Nanopore Technology
  2023 Black Forest Nanopore Meeting, Freiburg, 06.-09.11.2023
• T. Tu-Truong, Y. Kaku, S. ElGenk, M. Bösenberg, H. Sültmann, T. Gemoll, N. von Bubnoff, E. Dazert, L. Kubetzko, S. Derer, M. Oberländer, A. Katalinic, R. Deck, C. Sina, H. Busch, S. Kartmann, J. Lüddecke, T. Hutzenlaub, N. Paust, P. Juelg
  Robotic centrifugal microfluidics: a novel automation platform for large sample volume applications demonstrated by cell-free DNA isolation
  2023 MicroTAS 2023, Katovice/Poland, 15.-19.10.2023

2022

• T. Tu Truong, F. Schlenker, L. Karkossa, E. M. Arjmand, G. Grether, J. Lüddecke, U. A. Walker, S. Giaglis, N. Paust, T. Hutzenlaub, P. Juelg
  Towards standardization of pre-analytics: Highly efficient platelet-poor-plasma generation for ccfmtDNA analysis on a centrifugal microfluidic platform
  2022 EACR Liquid Biopsy, Bergamo, Italy, May 24-26, 2022

2021

• J.-N. Klatt, T.-L. Dinh, O. Schilling, R. Zengerle, F. Schmidt, T. Hutzenlaub, N. Paust
  Automation of Solid Phase Extraction for Peptide Desalting by Centrifugal Microfluidics
  2021 37th International Symposium on Microscale Separations and Bioanalysis 2021, Boston/USA (online), 12.-15.07.2021
• J.-N. Klatt, T.J. Dinh, N. Paust, R. Zengerle, F. Schmidt, O.Schilling, T. Hutzenlaub
  Automation of peptide desalting by centrifugal microfluidics
  2021 MicroTAS 2021, Palm Springs/USA, 10.-14.10.2021, online
• D. Kainz, B. Breiner, R. Zengerle, N. Paust, T. Hutzenlaub, S. M. Früh
  Determining binding kinetics of a PCT lateral flow assay during runtime
  2021 MicroTAS 2021, Palm Springs/USA, 10.-14.10.2021, online
• P. Juelg, E. Kipf, M. Specht, J. Menges, M. Fillies, C. Eckert, N. Paust, R. Zengerle, M. Lehnert, T. Hutzenlaub
  Die MRD Disk: Automatisiertes Monitoring Minimaler Resterkrankung durch hochsensitive, zentrifugal-mikrofluidische Multiplex-qPCR / The MRD disk: automated minimal residual disease monitoring by highly sensitive centrifugal microfluidic multiplex qPCR
  2021 MST
• F. Schlenker, L. Karkossa, N. Paust, R. Zengerle, S. Giaglis, U. A. Walker, T. Hutzenlaub, P. Juelg
  Generation of platelet poor plasma for circulating cell-free mitochondrial DNA analysis on a centrifugal microfluidic platform
  2021 Micro and Nano Engineering Conference, Turin, Italy, 20. – 23.09.2021
• L. Becherer, J.F. Hess, S. Frischmann, M. Bakheit, H. Nitschko, S. Stinco, F. Zitz, H. Hofer, G. Porro, F. Hausladen, K. Stock, D. Drossart, H. Wurm, H. Kuhn, D. Huber, T. Hutzenlaub, N. Paust, M. Keller, O. Strohmeier, S. Wadle, N. Borst, R. Zengerle, F. von Stetten
  Point-of-Care System for HTLV-1 Proviral Load Quantification by Digital Mediator Displacement LAMP
  2021 MST-Kongress, Ludwigsburg, 08.-10.11.2021

2020

• A. Brunauer, B. Breiner, S. Hennig, D. Kainz, R. Verboket, B. Johannsen, D. Baumgartner, K. Mitsakakis, L. Gutzweiler, Z. Shu, P. Koltay, T. Hutzenlaub, N. Paust, R. Zengerle, F. von Stetten, S. M. Früh
  Actuation principles for bioanalytical platforms to combat infectious diseases
  2020 Virtual EMBL Conference: Microfluidics: Designing the Next Wave of Biological Inquiry 2020, 13.-15.07.2020
• J. F. Hess, M. Kotrová, S. Calabrese, T. Hutzenlaub, R. Zengerle, M. Brüggemann, N. Paust
  Automated library preparation for next generation sequencing of immunoglobulin gene rearrangements by centrifugal microfluidics
  2020 MicroTAS 2020, 04.-09.10.2020, virtual
• F. Schlenker, E. Kipf, N. Borst, T. Hutzenlaub, N. Paust, R. Zengerle, F. von Stetten, P. Juelg
  Centrifugal microfluidic 4 Plex digital droplet PCR for quantification of circulating tumor DNA
  2020 MicroTAS 2020, 04.-09.10.2020, virtual
• F. Schlenker, E. Kipf, M. Deuter, I. Hoeffkes, N. Borst, T. Hutzenlaub, R. Zengerle, F. von Stetten, N. von Bubnoff, P. Juelg
  Low optimization effort for highly sensitive assays for point mutation quantification in CTDNA: the Mediator Probe digital PCR
  2020 Liquid Biopsy Symposium, 30.10.2020, virtuell

2019

• F. Schlenker, E. Kipf, S. Jenne, N. Borst, J. Lüddecke, K. Dormanns, T. Hutzenlaub, J. Steinert, N. Paust, R. Zengerle, F. von Stetten, P. Juelg
  Doubling the order of color-multiplexing by photobleaching in Mediator Probe droplet digital PCR
  2019 EACR-ESMO Joint Conference on Liquid Biopsies, Bergamo/Italien, 15. – 17. 05. 2019
• D. Kainz, S. M. Früh, T. Hutzenlaub, R. Zengerle, N. Paust
  Flow profile through exposed porous media in centrifugal microfluidics
  2019 MicroTAS, 27. – 31. October 2019, Basel/Switzerland
• P. Juelg, M. Specht, M. Meyer, E. Kipf, F. Schlenker, F. Baensch, S. Neumann, F. von Stetten, R. Zengerle, N. Paust, M. Fillies, R. Kirschner-Schwabe, S. Groeneveld-Krentz, M. Lehnert, C. Eckert, T. Hutzenlaub
  Individual Response Monitoring Assay (IRMA) – Standardization Of Personalized Multiplex Biomarker Quantification
  2019 EACR-ESMO Joint Conference on Liquid Biopsies, Bergamo/Italien, 15. – 17.05. 2019
• P. Juelg, M. Specht, M. Meyer, E. Kipf, F. Schlenker, F. Bänsch, S. Neumann, F. von Stetten, R. Zengerle, N. Paust, M. Fillies, R. Kirschner-Schwabe, S. Groeneveld-Krentz, M. Lehnert, C. Eckert, T. Hutzenlaub
  Standardization of Personalized Multiplex Biomarker Quantification: Individual Response Monitoring Assay (IRMA)
  2019 MST-Kongress, 28. - 30.Oktober 2019, Berlin
• S. M. Früh, D. M. Kainz, T. Hutzenlaub, R. Zengerle, N. Paust
  Tailor-made immunological reactions in lateral flow strips enables by total flow control
  2019 Wissenschaftsforum Chemie, Aachen, 15. -18.09.2019
• A. Brunauer, B. Breiner, D. Kainz, R. Verboket, F. von Stetten, R. Zengerle, N. Paust, T. Hutzenlaub, S. M. Früh
  Towards digital diagnostic devices - From smart membrane cartridges to highly integrated test stripes
  2019 Diagnostics-4-Future, 27. – 28. 11. 2019, Konstanz

2018

• P. Juelg, M. Specht, E. Kipf, M. Lehnert, C. Eckert, N. Paust, F. von Stetten, R. Zengerle, T. Hutzenlaub
  Automation of qPCR based Minimal Residual Disease Monitoring by Centrifugal Microfluidics
  2018 11th Symposium on minimal residual cancer, 03. – 05.05.2018, Montpellier, Frankreich
• J. F. Hess, S. Yazar, N. Paust, R. Zengerle, T. Hutzenlaub
  Capillary Valve for Microfluidic Foil Chips Fabricated by Micro-Milled Metal Master Tools
  2018 MicroTAS 2018, 11. -15. November 2018, Kaohsiung / Taiwan
• P. Juelg, M. Specht, E. Kipf, M. Lehnert, C. Eckert, N. Paust, R. Zengerle, T. Hutzenlaub
  LabDisk for fully automated quantification of two leukemia associated gene targets
  2018 MicroTAS 2018, 11. -15. November 2018, Kaohsiung / Taiwan
• D. Kainz, S. M. Früh, T. Hutzenlaub, R. Zengerle, N. Paust
  Total flow control for lateral flow tests with centrifugal microfluidics
  2018 MicroTAS 2018, 11. -15. November 2018, Kaohsiung / Taiwan
• P. Juelg, M. Specht, E. Kipf, M. Lehnert, C. Eckert, N. Paust, F. von Stetten, R. Zengerle, T. Hutzenlaub
  Towards Standardization of Molecular Diagnostic Workflows: Centrifugal Microfluidic Automation of qPCR for Cancer Monitoring
  2018 6th International Molecular Diagnostics Europe, Lissabon / Portugal, 22. - 24. 05.2018

2017

• P. Juelg, M. Specht, E. Kipf, M. Lehnert, C. Eckert, S. Wadle, M. Keller, N. Paust, R. Zengerle, T. Hutzenlaub
  Centrifugal microfluidic automation of dilution series for high dynamic range assays demonstrated for decadal dilutions up to 1:100,000
  2017 MicroTAS 2017, Savannah /USA, 22.-26.10.2017
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  Kurzfassung

  For the first time we present the centrifugal microfluidic automation of an extensive dilution series that can cover all biochemically relevant dilution ranges. In contrast to existing methods, the new concept is based on iteration loops of individual dilution steps that can be easily combined in a theoretically unlimited fashion. Thus, any combination and range of dilutions can be implemented. The concept was demonstrated by generating a qPCR standard curve for cancer biomarker ETV6-RUNX1 up to 1:100,000. We achieved the following analytical performance characteristics: A high coefficient of determination of R²=98.9 %, equidistant quantification cycles of ΔCq=3.4±0.3 and low replicate variation coefficients of CV<3.5 %.
• F. Schuler, N. Borst, S. Wadle, M. Schulz, M. Specht, J. Li, L. Becherer, T. Hutzenlaub, N. Paust, R. Zengerle, F. v. Stetten
  Eine Technologieplattform für die digitale Nukleinsäurediagnostik vor Ort (A Technology Platform for Digital Nucleic Acid Diagnostics at the Point of Care)
  2017 3. Münchner Point-of-Care-Testing Symposium der DGKL (Deutsche Gesellschaft für Klinische Chemie und Laboratoriumsmedizin e.V.) 13. – 15. März 2017, München

2015

• F. Stumpf, F. Schwemmer, T. Hutzenlaub, O. Strohmeier, F. von Stetten, R. Zengerle, D. Mark
  Automated sample-to-answer nucleic acid testing with frequency controlled reagent release from cartridge integrated stickpacks
  2015 18th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers 2015), Anchorage, Alaska, 21. – 25.06.2015 IEEE, Seiten: 743 - 746
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  Kurzfassung

  For the first time we demonstrate an automated centrifugal Lab-on-a-Disk system for sample-to-answer point-of-care testing of multiple nucleic acid targets that features pre-storage of all required liquid reagents for nucleic acid extraction as well as primers and probes and magnetic beads. Highly wetting and thus hardly controllable liquid buffers were pre-stored in stickpacks with frequency controlled on-demand reagent release enabling automated addition of binding buffer after sample lysis. The self-contained Lab-on-a-Disk system automates all necessary assay steps for PCR-based pathogen detection: RNA extraction, aliquoting of the RNA and geometrically multiplexed real-time RT-PCR. As a proof-of-principle, we demonstrated detection of as little as 15 plaque forming units (pfu) of RNA bacteriophage MS2 in a 200 µL sample in 3.5 hours.
• F. Stumpf, F. Schwemmer, T. Hutzenlaub, O. Strohmeier, F. von Stetten, R. Zengerle, D. Mark
  Automatisierte Nukleinsäurediagnostik in der LabDisk mittels frequenzgesteuerter Freisetzung vorgelagerter Reagenzien
  2015 6. Mikrosystemtechnik Kongress (MST Kongress 2015), Karlsruhe, 26. – 28.10.2015
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  Kurzfassung

  Präsentiert wird ein neues Verfahren zur automatisierten Sample-to-answer Point-of-Care Diagnostik auf der zentrifugal-mikrofluidischen LabDisk Plattform. Hochbenetzende und fluidisch schwer handhabbare Flüssigreagenzien für die Nukleinsäure-Extraktion werden in Stick-packs vorgelagert und können drehfrequenzgesteuert freigesetzt werden. Magnetische Beads, Primer und Fluoreszenzsonden werden durch Eintrocknung vorgelagert. Die LabDisk Plattform ermöglicht die Automatisierung aller erforderlichen Assayschritte der Pathogendetektion: RNA Extraktion und Aufreinigung, Aliquotieren der RNA sowie multiplex real-time RT-PCR. 15 PFU (plaque forming units) RNA-phage MS2 in einem 200 μL Sample werden in weniger als 3 Stunden detektiert.
• L. Zielke, R. Moroni, T. Hutzenlaub, D.R. Wheeler, I. Manke, T. Arlt, N. Paust, R. Zengerle, S. Thiele
  Modeling the missing carbon phase in X-ray tomographic reconstructions of a metal-based battery cathode
  2015 ModVal, 12th Symposium on Fuel Cell and Battery Modeling and Experimental Validation. Munzingen (Germany), 26. - 27.03.2015

2014

• L. Zielke, T. Hutzenlaub, D. R. Wheeler, I. Manke, T. Arlt, N. Paust, R. Zengerle, S. Thiele
  Combining X-ray tomography with virtual design in LiCoO2 electrodes
  2014 Gordon Research Seminar Batteries, Ventura/CA March 09.-14.03.2014
• I. Schwarz, S. Zehnle, G. Czilwik, T. Hutzenlaub, F. von Stetten, D. Mark, R. Zengerle, N. Paust
  Rapid development of centrifugal microfluidic assay automation by network-simulation based fluidic design
  2014 Biosensors 2014, Melbourne, Australia, 27.05.2014 – 30.05.2014

2013

• S. Thiele, T. Hutzenlaub, R. Zengerle
  A 3D water model in a tomographic reconstruction of a PEMFC cathode catalyst layer
  2013 Hydrogen + Fuel Cell Conference 2013 (HFC 2013) in Vancouver, Canada, 16. - 19.06.2013
  » Kurzfassung anzeigen« Kurzfassung verbergen
  Kurzfassung

  The cathode catalyst layer (CCL) of a polymer electrolyte membrane fuel cell (PEMFC), where the oxygen reduction reaction takes place, is still considered a major source for performance losses [1]. As transport processes within a CCL strongly depend on the morphology of the layer we introduced 3D PEMFC CCL reconstruction by Focused Ion Beam / Scanning Electron Tomography tomography (SEMt) in the past [3]. However, imaging the microstructure is only the first step towards understanding transport processes within the CCL. Water management is also a major factor influencing the PEMFC CCL performance [4]. We present a 3D water model in a CCL reconstruction of a commercial MEA that is able to depict hydrophilic and hydrophobic water distributions. We further show how this influences diffusion and active surface area. This can be considered as a first step towards understanding the influence of water management on performance.
• T. Hutzenlaub, A. Asthana, J. Becker, D.R. Wheeler, R. Zengerle, S. Thiele
  Calculation of tortuosity in a Li-ion battery cathode based on FIB/SEM tomography
  2013 Advances in Electrochemical Materials Science and Manufacturing; Pretoria, South Africa, 07. – 10.04.2013
• S. Thiele, T. Hutzenlaub, R. Zengerle
  Multi-scale tomography of nano-porous hydrogen fuel cell catalyst layers
  2013 5th International Conference on Porous Media & Annual Meeting in Prague, Tschechien, 21.-24.05.2013
• S. Thiele, T. Hutzenlaub, R. Zengerle
  Multi-scale tomography to understand mass transport limitations in the cathode catalyst layer of a PEMFC
  2013 Hydrogen + Fuel Cell Conference 2013 (HFC 2013) in Vancouver, Canada, 16. - 19.06.2013
  » Kurzfassung anzeigen« Kurzfassung verbergen
  Kurzfassung

  The cathode catalyst layer (CCL) of a polymer electrolyte membrane fuel cell (PEMFC ), where the oxygen reduction reaction occurs, has a major influence on PEMFC performance [1]. Optimizing transport of all reactants to reaction centers is central in the high current density regime where mass transport limitations occur [2]. In the past, we demonstrated that the pore structure in the CCL can be reconstructed using Focused Ion Beam / Scanning Electron Tomography tomography (SEMt) approaches [3]. SEMt resolution is however not high enough to image Pt catalyst morphologies. We developed an approach to combine SEMt with a Transmission Electron Microscopy tomographic (TEMt) approach within the same geometry. Thereby we include information from two different scales and two different tomographic techniques. For the first time we present results on diffusion time and electron transport time through the pore space to all imaged active centers. This is an important step to understand mass transport limitations in the CCL.

2012

• T. Hutzenlaub, R. Zengerle, S. Thiele
  Reconstruction of the active material, binder and pore space of a LiCoO2 Li-ion battery cathode
  2012 221st ECS Meeting Seattle, WA | May 6-10, 2012 , Seite: Nr. 547