Article
Chemistry, Analytical
Aodong Zhang, Jian Xu, Xiaolong Li, Zijie Lin, Yunpeng Song, Xin Li, Zhenhua Wang, Ya Cheng
Summary: This study proposes a method for the design and fabrication of a high-throughput micro free-flow electrophoresis (mu FFE) chip using laser-assisted chemical etching, electrode integration, and low-temperature bonding. The careful design of the height ratio of the separation chamber and electrode channels combined with a high flow rate of buffer solution allows for efficient removal of electrolysis-generated bubbles and enhances separation stability.
Article
Chemistry, Multidisciplinary
Alexandra C. Sun, Daniel J. Steyer, Richard I. Robinson, Carol Ginsburg-Moraff, Scott Plummer, Jinhai Gao, Joseph W. Tucker, Dirk Alpers, Corey R. J. Stephenson, Robert T. Kennedy
Summary: In the field of drug discovery, high-throughput experimentation techniques are used to optimize reactions and generate drug compound libraries quickly for evaluation. This study presents a segmented flow mass spectrometry-based platform to explore photoredox reactions in early-stage drug discovery. The technology enables fast analysis of photochemical reactions and evaluation of synthesized analogs, expanding the capabilities of photoredox catalysis in drug discovery.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Analytical
Se-woon Choe, Bumjoo Kim, Minseok Kim
Summary: Conventional membrane filtration techniques have limitations in the efficiency of separating biological particles, while microfluidic engineering allows for more efficient processing of rare biological samples in a continuous flow.
Article
Electrochemistry
Yingchao Liu, Yuanyu Huang, Mengxi Wu, Siyuan Kong, Weiqian Cao, Shunxiang Li, Guoquan Yan, Baohong Liu, Pengyuan Yang, Quanqing Zhang, Liang Qiao, Huali Shen
Summary: In this study, a novel microfluidic free-flow paper electrochromatography (mu-FFPE) method was developed by combining mu-FFE with filter paper-based chromatography, enabling continuous separation of charged analytes. The addition of filter paper as the stationary phase improved the stability of the separation system. The mu-FFPE showed great potential in the separation and analysis of various biological molecules.
Article
Chemistry, Analytical
Zdravko Siketic, Iva Bogdanovic Radovic, Marko Barac, Marko Brajkovic, Marijana Popovic Hadzija
Summary: MeV SIMS is a type of secondary ion mass spectrometry (SIMS) technique that uses MeV energy ions to desorb molecules from a sample surface. This study presents a new system for molecular imaging of organic materials using a continuous analytical beam and a start trigger based on the detection of secondary electrons. The system allows for the imaging of samples with a lateral resolution of about 20 μm and the analysis of samples of any thickness. The imaging capabilities of MeV SIMS are demonstrated on various samples to show its potential applications in biology and forensic science.
ANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
Jorvani Cruz Villarreal, Rory Kruithoff, Ana Egatz-Gomez, Paul D. Coleman, Robert Ros, Todd R. Sandrin, Alexandra Ros
Summary: Understanding cell-to-cell variation at the molecular level is critical for research and this study presents a microfluidic platform combined with MALDI-TOF-MS for the detection and quantification of targeted proteins from small cell ensembles. The integrated on-chip approach allows for protein quantification from cell lysate and demonstrates promising potential for single-cell analysis.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Mechanics
Desiree Ruiz-Martin, Javier Rivero-Rodriguez, Mario Sanchez-Sanz
Summary: This work focuses on the dynamics of solid particles flowing near a deformable interface formed by two co-flowing immiscible fluids in a microchannel. The study systematically analyzes the influence of various parameters on the hydrodynamic force exerted on the particles. The analysis includes both the pure inertial regime and the pure capillary regime, revealing the interaction mechanisms between the particles and the interface.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Chemistry, Multidisciplinary
Jan Leipert, Philipp T. Kaulich, Max K. Steinbach, Britta Steer, Konrad Winkels, Christine Blurton, Matthias Leippe, Andreas Tholey
Summary: Researchers have developed a sample preparation method based on protein aggregation and acidic elution, allowing for sensitive protein identification analysis of single nematodes on a digital microfluidics device. Compared to in-tube sample preparation, this method increases proteoform identifications by 46%. Label-free quantification also reveals changes in proteoform abundance that cannot be distinguished by bottom-up proteomics. This workflow facilitates proteoform-focused analysis on limited availability samples.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Physical
Dongxue Zhang, Liang Qiao
Summary: Population-level analysis masks heterogeneity between individual cells. Microfluidics coupled with mass spectrometry is a promising technique for studying single-cell omics. This review summarizes microfluidic chips designed for single-cell manipulation and discusses their applications in single-cell proteomics, metabolomics, lipidomics, and multi-omics.
Article
Engineering, Chemical
Yiyang Wang, Panagiotis Dimitrakopoulos
Summary: The study reveals that a constriction connecting two straight microchannels significantly facilitates lateral capsule migration compared to straight channels. Different migration mechanisms occur under different conditions, with increased interfacial deformation leading to increased lateral cross-streamline migration in downstream straight channels.
Article
Multidisciplinary Sciences
Dongxue Zhang, Fan Yin, Qin Qin, Liang Qiao
Summary: Bacterial antimicrobial resistance (AMR) is a major challenge to current society, and understanding the molecular changes during bacterial self-saving responses can lead to new inhibition methods. This study used microfluidics mass spectrometry to identify metabolic changes in extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-E. coli) during filamentation. The up-regulation of cyclic dinucleotide c-di-GMP, which is related to bacterial resistance and tolerance, was observed. By inhibiting the synthesis of c-di-GMP through a chemical inhibitor, the minimum inhibitory concentration of ceftriaxone against ESBL-E. coli was significantly decreased. This study uncovers molecular changes during bacterial filamentation and proposes a method to inhibit antibiotic-resistant bacteria.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Analytical
Kevin Jooss, Luis F. Schachner, Rachel Watson, Zachary B. Gillespie, Sarah A. Howard, Marcus A. Cheek, Matthew J. Meiners, Amin Sobh, Jonathan D. Licht, Michael-Christopher Keogh, Neil L. Kelleher
Summary: The study introduces a new platform for separating and characterizing whole nucleosomes and their modifications, aiding in understanding epigenetic regulatory mechanisms. The platform offers low sample requirements and costs, with high detection sensitivity.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Analytical
Renata Konasova, Maria Butnariu, Veronika Solinova, Vaclav Kasicka, Dusan Koval
Summary: Charged polymer coatings on the inner fused silica capillary wall enable tunable electroosmotic flow velocity for optimizing peak resolution and separation efficiency in capillary electrophoresis.
ANALYTICA CHIMICA ACTA
(2021)
Review
Chemistry, Analytical
Tomoyoshi Soga
Summary: Capillary electrophoresis mass spectrometry (CE-MS) is a powerful tool for comprehensive analysis of low-molecular-weight charged metabolites. This review discusses the strategies and principles of CE-MS-based metabolomics analyses, including sample preparation, CE separation modes, interfacing techniques, and mass spectrometers. Additionally, it highlights new techniques to increase throughput ability in CE-MS for metabolomics.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2023)
Review
Chemistry, Analytical
Ketki Bagwe, Noah Gould, Kendall R. Johnson, Alexander R. Ivanov
Summary: Tissues and cell populations exhibit high levels of heterogeneity at the cellular level, making it important to analyze smaller sample sizes to capture subtle differences between cells. Capillary electrophoresis coupled with mass spectrometry (CE-MS) is a powerful technique for proteomics and metabolomics analysis at the single-cell level, and this review focuses on its applications and recent advances in sample preparation, separation, MS acquisition, and data analysis.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
Benjamin Krafft, Rajapandiyan Panneerselvam, David Geissler, Detlev Belder
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2020)
Article
Chemistry, Analytical
Sebastian K. Piendl, David Geissler, Laura Weigelt, Detlev Belder
ANALYTICAL CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Rico Warias, Daniele Ragno, Alessandro Massi, Detlev Belder
CHEMISTRY-A EUROPEAN JOURNAL
(2020)
Article
Biochemical Research Methods
Benjamin Krafft, Anna Tycova, Raphael D. Urban, Christian Dusny, Detlev Belder
Summary: This study introduces a disposable and low-cost lab-on-a-chip device utilizing a nanoporous membrane for the identification of bacterial pathogens in drinking water. The device showed promising results in rapid and reliable pathogen detection, making it suitable for common pathogens in spiked tap water.
Article
Chemistry, Analytical
Martin Schirmer, Konstantin Wink, Stefan Ohla, Detlev Belder, Andreas Schmid, Christian Dusny
ANALYTICAL CHEMISTRY
(2020)
Article
Biochemical Research Methods
Chris Pruefert, Raphael David Urban, Tillmann Georg Fischer, Jose Villatoro, Daniel Riebe, Toralf Beitz, Detlev Belder, Kirsten Zeitler, Hans-Gerd Loehmannsroeben
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2020)
Article
Biochemical Research Methods
Raphael D. Urban, Tillmann G. Fischer, Ales Charvat, Konstantin Wink, Benjamin Krafft, Stefan Ohla, Kirsten Zeitler, Bernd Abel, Detlev Belder
Summary: This approach involves generating droplets of non-polar solvents in an aqueous matrix and ionizing the solutes with an IR laser for mass spectrometric analysis at atmospheric pressure. It works for both non-polar solvents such as n-heptane and water non-miscible solvents like chloroform. It has been successfully applied to monitor the photooxidation of N-phenyl-1,2,3,4-tetrahydroisoquinoline in a proof of concept study.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2021)
Article
Biochemical Research Methods
Sadat Hasan, Maximilian E. Blaha, Sebastian K. Piendl, Anish Das, David Geissler, Detlev Belder
Summary: This research introduces a label-free detection technique using time-resolved two-photon excitation (TPE) fluorescence detection at 532 nm in droplet microfluidics. A polydimethylsiloxane-fused silica (FS) hybrid chip was developed to provide high optical transparency in the deep-UV range and suitable surface properties for droplet microfluidics. The system incorporating a 532-nm picosecond laser, time-correlated single-photon counting (TCSPC), and a chip-integrated dielectrophoretic pulsed actuator was utilized to sort droplets containing specific compounds and screen yeast cells based on their protein autofluorescence.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Nora T. Hartner, Konstantin Wink, Christian-Robert Raddatz, Christian Thoben, Martin Schirmer, Stefan Zimmermann, Detlev Belder
Summary: The coupling of droplet microfluidics and high-resolution drift tube IMS system enables chemical-specific monitoring of reactions in droplets at single droplet level, achieving limit of detections down to 200 nM to 1 µM. This approach is cost-effective and robust, making it ideal for chemical-specific end-of-line detection for segmented flow experiments.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Konstantin Wink, Marie van Der Loh, Nora Hartner, Matthias Polack, Christian Dusny, Andreas Schmid, Detlev Belder
Summary: Chemically specific and quantifiable monitoring of biocatalytic transformations at the single-cell level has been achieved through the integration of droplet microfluidics, cell imaging, and mass spectrometry.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Analytical
Anish Das, Sebastian Fehse, Matthias Polack, Rajapandiyan Panneerselvam, Detlev Belder
Summary: We present a new approach for surface-enhanced Raman spectroscopy (SERS) detection in digital microfluidics (DMF) using a microspray hole (mu SH) that utilizes electrostatic spray (ESTAS) for sample transfer. A novel ESTAS-compatible stationary SERS substrate was developed and characterized for sensitive and reproducible SERS measurements. Proof-of-concept experiments showed successful detection of various analyte molecules with micro-molar detection limits using the DMF chip and provided vibrational spectroscopic data of an organic reaction occurring in the DMF device.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Tobias Haensch, Franziska D. Zitzmann, Heinz-Georg Jahnke, Maximilian E. Blaha, Erik Paternoga, Kirsten Zeitler, Detlev Belder, Andrea A. Robitzki
Summary: This article introduces the miniaturization and integration of chemical reactions into fluidic systems to reduce solvent and reactant usage while increasing synthesis efficiency. Real-time, label-free monitoring is achieved through electrochemical impedance spectroscopy. The optimization of electrode structures in microfluidic channels allows for sensitive detection and quantification of compounds like propranolol. The integrated electrodes also enable the monitoring and control of fluidic flows for purification processes during free-flow electrophoresis.
Article
Chemistry, Multidisciplinary
Hannes Westphal, Rico Warias, Chris Weise, Daniele Ragno, Holger Becker, Matthias Spanka, Alessandro Massi, Roger Glaser, Christoph Schneider, Detlev Belder
Summary: A highly integrated microfluidic device is developed for parallel study of stereoselective heterogeneous catalytic processes. It combines multiple packed-bed mu-flow reactors with a chiral separation unit on a chip, seamlessly connected to mass spectrometry. The device allows automated fluidic setup and enables the study of different catalysts' performance using small amounts of resources.
REACTION CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Analytical
Nora T. Hartner, Christian-Robert Raddatz, Christian Thoben, Sebastian K. Piendl, Stefan Zimmermann, Detlev Belder
ANALYTICAL CHEMISTRY
(2020)
Article
Biochemical Research Methods
Andrea J. Peretzki, Sabine Schmidt, Elias Flachowsky, Anish Das, Renata F. Gerhardt, Detlev Belder
