Article
Chemistry, Analytical
Yao Xiao, Xin Wang, Enyou Li, Yiping Liu, Dandan Jiang, Mei Li, Chuang Chen, Haiyang Li
Summary: The newly developed method enables rapid and accurate determination of blood propofol concentration, without the need for sample pretreatment, in less than 1 minute. The dual calibration quantitative method successfully achieved accurate quantification of blood propofol.
ANALYTICA CHIMICA ACTA
(2021)
Article
Chemistry, Analytical
Vitaly A. Kostarev, Gennadii E. Kotkovskii, Alexander A. Chistyakov, Artem E. Akmalov
Summary: This study investigates the sensing capability of the FAIMS detector for nitro-explosives using dopants toluene and 1-methylnaphtalene combined with ultraviolet laser ionization. The results demonstrate that the presence of dopants leads to a significant increase in ion yield at lower laser intensities. Dopant-assisted laser ionization improves the limits of detection, suggesting a potential way to enhance the sensitivity of detectors and improve the portability of laser-based FAIMS prototypes.
Article
Chemistry, Analytical
Lingfeng Li, Hao Gu, Yanzhen Lv, Yunjing Zhang, Xingli He, Peng Li
Summary: Drift-time ion mobility spectrometer (DT-IMS) is a promising technology for gas detection and analysis in a miniaturized instrument. This study investigated the polarity switching of a DT-IMS based on a direct current (DC) corona discharge ionization source and proposed novel solutions for ion shutter control and aperture grid stabilization. By using a switchable high voltage power supply, voltage regulator diodes, optocouplers, and diodes, the developed DT-IMS was able to switch polarity within 10 ms and acquire mobility spectrum after 10 ms of stabilization. The system achieved a limit of detection (LoD) of 0.1 ng for ketamine and TNT when combined with a thermal desorption sampler. The work also led to simplified pneumatic design and reduction of necessary components. This research opens up possibilities for further miniaturization of DT-IMS without compromising its performance.
Article
Physics, Atomic, Molecular & Chemical
Liulin Deng, Jason M. LaForest, Gordon A. Anderson, John Daniel DeBord
Summary: A new high sensitivity, high-resolution platform was developed using SLIM ion mobility filter with QQQ-MS to enhance performance for targeted quantitative analysis. The experimental results demonstrated that the SLIM-QQQ approach significantly improved ion utilization efficiency and detection/quantification limits in various operating modes.
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
(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)
Article
Chemistry, Analytical
Andre Ahrens, Maria Allers, Henrike Bock, Moritz Hitzemann, Arne Ficks, Stefan Zimmermann
Summary: There is a growing demand for low-cost gas sensors that can detect small amounts of highly toxic substances in the air, including chemical warfare agents and toxic industrial chemicals. Ion mobility spectrometers are particularly suitable for this application due to their high sensitivity and fast response times.
ANALYTICAL CHEMISTRY
(2022)
Article
Biochemical Research Methods
Andrea McCann, Christopher Kune, Philippe Massonnet, Johann Far, Marc Ongena, Gauthier Eppe, Loic Quinton, Edwin De Pauw
Summary: With improved ion mobility resolution, it is now possible to separate small protomeric tautomers. This study observed the presence of protomers in the molecule surfactin, supporting the idea that protomeric tautomerism can still be observed in molecules above 1000 Da.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2022)
Article
Chemistry, Analytical
Binwang Yang, Jianna Yu, Wen Liu, Guoxing Jing, Wenshan Li, Wenjie Liu
Summary: Drift tube ion mobility spectrometer (IMS) has been widely recognized as the preferred equipment for on-site monitoring and identification of volatile organic compounds (VOCs) due to its simplicity, reliability, and sensitivity. This study presents a low-cost, miniaturized IMS with improved sensitivity and resolving power through the implementation of Fourier deconvolution multiplexing. Experimental evaluation demonstrates satisfactory performance of the developed spectrometer for the detection of various compounds.
Article
Chemistry, Analytical
Alexander Brzhozovskiy, Alexey Kononikhin, Anna E. Bugrova, Grigoriy Kovalev, Pierre-Olivier Schmit, Gary Kruppa, Evgeny N. Nikolaev, Christoph H. Borchers
Summary: Mass spectrometry-based quantitative proteomic methods, such as prm-PASEF, are important tools for protein biomarker discovery and validation. This study demonstrated the use of prm-PASEF for absolute protein quantitation in human plasma, with improved sensitivity and a broad dynamic range. The prm-PASEF method showed excellent correlation with MRM, highlighting its suitability for absolute quantitative proteomics.
ANALYTICAL CHEMISTRY
(2022)
Article
Biochemical Research Methods
O. Tara Liyanage, Ana Quintero, Jacob B. Hatvany, Elyssia S. Gallagher
Summary: This study presents a rapid hydrogen/deuterium exchange mass spectrometry method for analyzing solvated carbohydrates, by adjusting the reaction time through modifying the spray-solvent conductivity. The research demonstrates that monitoring hydrogen/deuterium exchange at multiple time points allows for the differentiation of three trisaccharide isomers with distinct structures.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2021)
Article
Chemistry, Analytical
Kelly L. Wormwood Moser, Gregory Van Aken, Daniel DeBord, Nathan Galen Hatcher, Laura Maxon, Melissa Sherman, Lihang Yao, Kim Ekroos
Summary: Defects in sphingolipid metabolism serve as a common link in various neurodegenerative disorders, and a better understanding of lipid content presents opportunities for the development of new therapeutic targets and biomarkers.
ANALYTICA CHIMICA ACTA
(2021)
Article
Chemistry, Analytical
Wanzhen Han, Shiyu Du, Caowei Tang, Yiling Li, Ting Jiang, Wei Xu
Summary: The integration of a liquid-phase ion trap with a miniature mass spectrometer improves detection sensitivity and enables enrichment and separation of ions, making it suitable for the analysis of low abundant target molecules.
ANALYTICA CHIMICA ACTA
(2022)
Article
Chemistry, Applied
Badrul Hisyam Zainudin, Salsazali Salleh, Abdul Syukur Yaakob, Rahmat Mohamed
Summary: A multiresidue quantitative and qualitative screening method for pesticide residues in dried cocoa beans was validated and applied successfully, with 32% of samples testing positive for specific pesticides in routine analysis.
Article
Chemistry, Analytical
Yao Xiao, Hang Li, Yan Liu, Chuang Chen, Huaiwen Cang, Mei Li, Yiqian Xu, Qimu Yang, Xin Wang, Haiyang Li
Summary: A method for determining the concentration of etomidate in blood was developed using positive photoionization ion mobility spectrometry, increasing detection sensitivity. Additionally, the use of pulse purge thermal desorption in bidirectional flow injection method improved analysis performance and reduced the impact of pressure fluctuation on quantitative accuracy.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Analytical
Patrick O. Helmer, Ilona D. Nordhorn, Ansgar Korf, Arne Behrens, Rebecca Buchholz, Florian Zubeil, Uwe Karst, Heiko Hayen
Summary: The study focuses on identifying complex lipid species using high-resolution mass spectrometry and separation methods, with enhanced accuracy through collision cross section and TIMS technology. The main emphasis is on distinguishing isomeric and isobaric lipid classes.
ANALYTICAL CHEMISTRY
(2021)
Article
Biochemical Research Methods
Ansgar T. Kirk, Torben Last, Stefan Zimmermann
JOURNAL OF CHROMATOGRAPHY A
(2017)
Article
Instruments & Instrumentation
E. Bunert, A. Heptner, T. Reinecke, A. T. Kirk, S. Zimmermann
REVIEW OF SCIENTIFIC INSTRUMENTS
(2017)
Article
Chemistry, Analytical
A. Heptner, T. Reinecke, N. Angerstein, S. Zimmermann
SENSORS AND ACTUATORS B-CHEMICAL
(2017)
Article
Chemistry, Analytical
T. Reinecke, P. Biechele, M. Sobocinski, H. Suhr, K. Bakes, D. Solle, H. Jantunen, T. Scheper, S. Zimmermann
SENSORS AND ACTUATORS B-CHEMICAL
(2017)
Review
Chemistry, Analytical
Mashaalah Zarejousheghani, Parvaneh Rahimi, Helko Borsdorf, Stefan Zimmermann, Yvonne Joseph
Summary: There is growing global concern about the health risks of water and air pollution, with EPA listing 129 different chemical compounds as priority pollutants. Long-term exposure to these chemicals can cause severe health effects, and MIPs show great potential for developing sensors to detect these pollutants.
Article
Chemistry, Analytical
Jens Twiefel, Anatoly Glukhovkoy, Sascha de Wall, Marc Christopher Wurz, Merle Sehlmeyer, Moritz Hitzemann, Stefan Zimmermann
Summary: This paper presents a novel approach for a co-resonant mass detector, addressing the challenge of detecting exceedingly small masses while simplifying setup and improving sensitivity. By combining longitudinal and bending vibrations and integrating an aluminum nitride piezoelectric element for excitation and sensing, the feasibility of the concept is demonstrated and shown to be a promising approach for future nano-mass detectors.
Article
Chemistry, Analytical
Marc Berger, Anne Zygmanowski, Stefan Zimmermann
Summary: A differential transformer has been used to measure directly through electrically non-conductive tubing, with radial winding showing higher sensitivity compared to longitudinal winding. This study demonstrates the potential for using the differential transformer as a truly contactless sensing system.
Article
Chemistry, Analytical
Ryoichi Nakagawa, Kai Saito, Hideyuki Kanematsu, Hidekazu Miura, Masatou Ishihara, Dana M. Barry, Takeshi Kogo, Akiko Ogawa, Nobumitsu Hirai, Takeshi Hagio, Ryoichi Ichino, Masahito Ban, Michiko Yoshitake, Stefan Zimmermann
Summary: Biofilms are the result of bacterial activity and a sensor that can detect biofilms is important. Graphene, which easily bonds with carbon compounds, could serve as a sensor for monitoring biofilm formation and growth. Previous research showed that CVD graphene film has higher sensitivity for biofilm formation. This new research focuses on preparing bilayer graphene with high mechanical strength to overcome the mechanical disadvantage of monolayer graphene when used as a biofilm sensor.
Article
Computer Science, Information Systems
Moritz Hitzemann, Kirsten J. Dehning, Adrian Gehl, Erk-Fietje Sterr, Stefan Zimmermann
Summary: Split-ring resonators (SRR) are simple electrical circuits that show a significant shift in resonance frequency even with the smallest changes in split capacitance. We present a new capillary split-ring resonator CaSRR, which is capable of accurately detecting very fast changes in split capacity. The proposed method is based on the analysis of the transmitted signal at a single frequency using demodulation.
Article
Computer Science, Information Systems
Moritz Hitzemann, Martin Lippmann, Jonas Trachte, Alexander Nitschke, Olaf Burckhardt, Stefan Zimmermann
Summary: This paper introduces a new concept of an isolated power supply for electronic components, with high insulation strength and power transmission, achieving high overall efficiency. Through the use of a coreless PCB transformer and investigation of different coil geometries, as well as comparison with a low-cost design, high efficiency and high insulation voltage are achieved.
Article
Computer Science, Information Systems
Jonas Winkelholz, Moritz Hitzemann, Alexander Nitschke, Anne Zygmanowski, Stefan Zimmermann
Summary: Resistive voltage dividers tend to have a highly non-linear transfer function due to the influence of parasitic and stray capacitances. This article presents an improved resistive voltage divider with additional compensation capacities to extend the linear bandwidth. The performance of this new voltage divider is demonstrated by measuring high-voltage pulses.
Article
Chemistry, Analytical
Kirsten J. Dehning, Moritz Hitzemann, Alexander Gossmann, Stefan Zimmermann
Summary: Amino acids play a vital role in life as they are essential components of proteins and necessary for cell growth and maintenance. This study introduces a split-ring resonator as a sensitive and simple detector for amino acids. The split-ring resonator uses the electromagnetic properties of a liquid sample to determine the resonance frequency, and initial measurements show detection limits for tested amino acids ranging from 105 μM to 1564 μM. With an envelope detector, the split-ring resonator can be used in ion chromatography and achieve detection limits of 485 μM for aspartic acid and 956 μM for lysine at a flow rate of 0.5 mL/min.
Proceedings Paper
Engineering, Electrical & Electronic
Erik Bunert, Andre Heptner, Ansgar T. Kirk, Oliver Kaebein, Stefan Zimmermann, Alexander Kusch, Marc Christopher Wurz
2017 30TH INTERNATIONAL VACUUM NANOELECTRONICS CONFERENCE (IVNC)
(2017)
Article
Spectroscopy
Ansgar T. Kirk, Kai Bakes, Stefan Zimmermann
INTERNATIONAL JOURNAL FOR ION MOBILITY SPECTROMETRY
(2017)
Article
Chemistry, Analytical
Ansgar T. Kirk, Christian-Robert Raddatz, Stefan Zimmermann
ANALYTICAL CHEMISTRY
(2017)
