Article
Chemistry, Analytical
Yuanji Gao, Yuan Li, Binpeng Zhan, Quan He, Heping Zhu, Weiwei Chen, Qi Yin, Hongru Feng, Yuanjiang Pan
Summary: The ambient electric arc ionization (AEAI) device is a novel and convenient ion source for mass spectrometry that can be used for versatile sample analysis. It is considered a soft ionization technique with the protonated ion as the main species. AEAI coupled with a high-resolution Orbitrap mass spectrometer can analyze a variety of organic compounds with different polarities, potentially serving as an alternative to traditional ionization methods.
Article
Chemistry, Analytical
Vincen Wu, Jocelyn Tillner, Emrys Jones, James S. McKenzie, Dipa Gurung, Anna Mroz, Liam Poynter, Daniel Simon, Cristina Grau, Xavier Altafaj, Marc-Emmanuel Dumas, Ian Gilmore, Josephine Bunch, Zoltan Takats
Summary: This study examines the suitability of desorption electro-flow focusing ionization (DEFFI) for mass spectrometry imaging (MSI) of biological tissue, comparing its performance to the traditional desorption electrospray ionization (DESI). The flow focusing mechanism in DESI offers advantages such as a rotationally symmetric electrospray jet, higher intensity, controllable parameters, and better portability. The optimized parameters for DEFFI result in similar images to DESI but with better sensitivity.
ANALYTICAL CHEMISTRY
(2022)
Review
Chemistry, Analytical
Sarmila Amatya Shrestha, Sangwon Cha
Summary: The paper reviews the application of ambient desorption/ionization mass spectrometry in the direct analysis of solid materials, covering various sampling and desorption processes. Real-world analysis cases include pharmaceuticals, food products, forensic analysis, and surface contaminant analysis. ADI techniques provide efficient and simplified methods for direct desorption and ionization of analytes from untreated samples under ambient conditions.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Analytical
Nattapong Chantipmanee, Jasmine S. Furter, Peter C. Hauser
Summary: The instrument is based on a miniature plasma source, which enables rapid identification of different drugs and components in coffee, with the advantages of low cost and easy replication.
ANALYTICA CHIMICA ACTA
(2022)
Article
Chemistry, Analytical
Taghi Sahraeian, Enoch Amoah, Dmytro S. Kulyk, Abraham K. Badu-Tawiah
Summary: A high-throughput droplet imbibition mass spectrometry experiment was developed for direct analysis of ultra-small volumes of complex mixtures. This method utilizes glass capillaries and charged microdroplets to sample and transfer the analyte, resulting in increased sensitivity and analysis efficiency.
ANALYTICAL CHEMISTRY
(2023)
Article
Instruments & Instrumentation
George C. -Y. Chan, Carsten Engelhard, Joshua S. Wiley, Ayanna U. Shoulds, R. Graham Cooks, Gary M. Hieftje, Jacob T. Shelley
Summary: In this paper, the optical spectroscopy of the low-temperature plasma (LTP) probe and its interaction with a sample substrate and a grounded metallic needle were investigated. It was found that the LTP probe exhibits important spectral characteristics under certain conditions, which are correlated with the mass-spectral results. Temporally and spatially resolved imaging provided insights into important processes in the LTP plasma jet.
APPLIED SPECTROSCOPY
(2023)
Article
Chemistry, Analytical
Keguo Teng, Jianbo Shi, Yanping Zhu, Quan Yu
Summary: New ionization sources are driving the growth and application of mass spectrometry analysis. This study introduces a new voltage-free ionization method called micro-tapered aperture nebulization ionization (MANI), which utilizes a common micro-tapered aperture atomizer. It is discovered that liquid nebulization on this type of atomizer can ionize the dissolved analytes in droplets without requiring additional voltage and gas. By constructing a compact MANI source using a commercially available atomizer module in a 3D-printed chamber, high ion yield and satisfactory quantitative performance are achieved, making it ideal for analyzing aqueous solutions. The MANI source demonstrates broad applicability and can be easily extended to other applications, such as liquid extraction surface analysis and direct analysis of gaseous analytes.
ANALYTICAL METHODS
(2022)
Review
Chemistry, Analytical
Vera Plekhova, Kimberly De Windt, Margot De Spiegeleer, Marilyn De Graeve, Lynn Vanhaecke
Summary: Biofluid metabolomics is a valuable tool for discovering biomarkers related to disease, genetics, and exposure. Direct infusion and ambient ionization mass spectrometry offer attractive alternatives for rapid analysis with minimal sample handling.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Ivan Prokhorov, Joachim Mohn
Summary: The relative abundance of methane isotopologues provides valuable insights into the global methane cycle. A new preconcentration device called CleanEx has been developed, which allows for quantitative extraction of methane from large volumes of sample gas and enables precise monitoring of methane isotopes from ambient air to process-derived methane.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yue Wu, Ho-Fai Chau, Yik-Hoi Yeung, Waygen Thor, Hei-Yui Kai, Wai-Lun Chan, Ka-Leung Wong
Summary: In this study, a novel synthetic method for the efficient preparation of prefunctionalized core porphyrins and the controllable construction of various valent porphyrin-peptide conjugates was reported. Compared to traditional methods, this approach is faster, greener, and requires only one final-stage purification.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Materials Science, Ceramics
Bo Chen, Norbert Willenbacher
Summary: Due to its high ionic conductivity and stability to lithium metal, Li6.4La3Zr1.4Ta0.6O12 (LLZTO) has become one of the most promising solid electrolyte materials. However, traditional processing technologies lack structural diversity and complexity, making it difficult to be widely used in industrial production. This study presents three LLZTO ink formulations that can be printed with excellent properties, allowing for the fabrication of complex 3D structures.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Engineering, Biomedical
Nafiseh Rafiei, Mohammadamir G. Moghadam, Aaron Au, Romario Regeenes, Subbulakshmi Chidambaram, Tao Liang, Yufeng Wang, Christopher M. Yip, Herbert Gaisano, Jonathan Rocheleau
Summary: This article introduces a versatile microfluidic device for 3D fluorescence imaging of mouse or human pancreas PCTs, positioning them within a chamber with tall channels for media exchange. The device localizes shear stress to small regions on tissue surfaces and allows for controlled media exchange at lower flowrates than conventional chambers. It enables high-resolution imaging of immunofluorescently labeled PCTs on a confocal and with a large field of view on a SPIM without compromising image quality.
Article
Biochemical Research Methods
Li-Xue Jiang, Matthias Polack, Xiangtang Li, Manxi Yang, Detlev Belder, Julia Laskin
Summary: Novel laser-assisted etching of a fused silica microfluidic probe for liquid extraction-based ambient mass spectrometry imaging provides a simplified and scalable fabrication method for robust monolithic microfluidic probes. Evaluation on mouse tissue sections demonstrates the capability of this technology.
Article
Chemistry, Analytical
Xuechao Pang, Shanshan Gao, Man Ga, Jin Zhang, Zhigang Luo, Yanhua Chen, Ruiping Zhang, Jiuming He, Zeper Abliz
Summary: The method developed can map hundreds of different polar functional metabolites in the rat brain, including neurotransmitters, purines, organic acids, polyamines, cholines, and carbohydrates. It was also used to discover dysregulated metabolites and brain microregions involved in the pathology of Alzheimer's disease. Additionally, the methodology serves as a powerful visualizing tool for exploring metabolic events in central nervous system diseases.
ANALYTICAL CHEMISTRY
(2021)
Article
Biochemical Research Methods
Liping Xu, Kai Zhang, Xin Geng, Hongli Li, David Da Yong Chen
Summary: A modified method was used for analyzing human metabolites in exhaled breath, providing a more complete picture of the human breath metabolome. The method allows rapid and direct analysis of breath samples with different status, featuring simple operation and metabolite identification, requiring little or no sample preparation.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2022)
Review
Spectroscopy
Michael Caleb Bagley, Kenneth P. Garrard, David C. Muddiman
Summary: In the past 15 years, ambient ionization techniques, particularly matrix-assisted laser desorption electrospray ionization, have made significant advancements in mass spectrometry imaging. These techniques have been developed and improved with different laser systems and mass spectrometers, leading to transformative developments in the imaging platform.
MASS SPECTROMETRY REVIEWS
(2023)
Article
Biochemical Research Methods
Cristina Arciniega, Kenneth P. Garrard, Jacob P. Guymon, Jeffrey G. Manni Sr, Alex Apffel, John C. Fjeldsted, David C. Muddiman
Summary: High-throughput screening (HTS) is a technique used by pharmaceutical companies to quickly screen multiple compound libraries for potential drugs. Mass spectrometry (MS) is a popular choice for HTS because it can analyze hundreds to thousands of compounds simultaneously without additional chemical derivatization. In this study, we developed an infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) source coupled directly to an Agilent 6545 mass spectrometer for direct analysis from well plates. The source used a laser operating at 100 Hz with high ionization efficiency, and a metal capillary was constructed to improve ion transmission and sensitivity.
JOURNAL OF MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Ying Xi, Alexandria L. Sohn, Alena N. Joignant, Stephanie M. Cologna, Boone M. Prentice, David C. Muddiman
Summary: Mass spectrometry imaging (MSI) is an important analytical technique for reporting the spatial location and abundance of detected ions in various studies. However, the lack of consistency in data reporting creates challenges in comparing MSI data. To address this issue, a unified data reporting system called SMART is proposed, which aims to capture essential baseline information for MSI studies. The tutorial emphasizes the necessity of establishing a uniform reporting system to facilitate the interpretation and comparison of MSI data.
JOURNAL OF MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Hongxia Bai, Jeffrey G. Manni Sr, David C. Muddiman
Summary: Infrared laser used in mass spectrometry imaging often leads to nonuniform ablation due to its Gaussian profile, which decreases image quality. To address this issue, researchers integrated a diffractive optical element into the optical path to generate homogeneous intensity distribution, ensuring complete sample removal with laser pulses.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Seth M. Eisenberg, Kevan T. Knizner, David C. Muddiman
Summary: Mass spectrometry imaging (MSI) is an analytical technique that detects and visualizes thousands of m/z values in two- and three-dimensional space. Discriminating sample-related analytes from ambient ions conventionally requires manual investigation of each ion heatmap, which is time-consuming and subjective. In this study, an ion classification tool (ICT) was developed using object-based image analysis in MATLAB, which accurately classified ions as on-tissue or background based on binary conversion and the number of detected objects.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
Alena N. N. Joignant, Ying Xi, David C. C. Muddiman
Summary: Biospecimens with flat surfaces are needed for laser-based mass spectrometry imaging. However, imperfections in the sampling stages and non-flat samples require a deeper understanding of the laser beam's depth of focus. This tutorial explores the parameters and equations that describe the depth of focus of a Gaussian laser beam and presents methods to address surface roughness exceeding the laser's depth of focus.
JOURNAL OF MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Russell R. Kibbe, David C. Muddiman
Summary: Profile data collection in mass spectrometry imaging (MSI) studies often results in large files and long processing times. This study compares profile and centroid data collection methods in high-resolution accurate mass MSI. The results show that centroid data collection improves mass measurement accuracy and lipid annotation sensitivity compared to profile data collection.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Mary F. Wang, Alexandria L. Sohn, Juhi Samal, Kevin Erning, Tatiana Segura, David C. Muddiman
Summary: Two preparatory methods for mass spectrometry imaging (MSI), fresh-frozen and sucrose-embedded, paraformaldehyde (PFA) fixed, were evaluated in terms of ion abundance, putative lipid identifications, and preservation of analyte spatial distributions. Sucrose-embedded, PFA-fixed tissues without an ice matrix showed significantly higher numbers of putatively identified lipid species in positive and negative ion modes compared to the traditional gold-standard fresh-frozen tissue preparation with an exogenous ice matrix. Sucrose-embedded tissues also demonstrated improved spatial distribution of ions. These findings support sucrose-embedding without ice matrix as an alternative preparatory technique for IR-MALDESI-MSI.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Tana V. Palomino, David C. Muddiman
Summary: This study presents a new rule that can predict the number of sialic acids on a glycan. By utilizing infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) in negative-ion mode mass spectrometry, the number of sialic acids on the glycan can be predicted based on the experimental isotopic distribution of a detected glycan. This new rule improves the capability of IR-MALDESI to analyze sialylated N-linked glycans within biological tissues, providing confident glycan annotations and compositions.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Ying Xi, Kevan T. T. Knizner, Kenneth P. P. Garrard, David C. C. Muddiman
Summary: This study presents a mass spectrometry imaging (MSI) method that automatically corrects discernible height differences across surfaces during imaging experiments. A chromatic confocal sensor is incorporated into the infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) system to measure the sample surface height at each analytical scan location, allowing for adjustment of the z-axis position of the sample during MSI data acquisition. The method is evaluated using a tilted mouse liver section and an unsectioned Prilosec tablet, showing consistent ablated spot sizes and shapes and revealing the measured ion spatial distribution.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Mary F. Wang, Morgan M. Ritter, Seth W. Kullman, David C. Muddiman
Summary: In this study, the feasibility of sucrose-embedding with paraformaldehyde fixation as an alternative matrix for IR-MALDESI analysis in whole-body zebrafish samples was investigated. The results demonstrated that sucrose-embedding method obtained more lipid annotation information compared to the conventional fresh-frozen sample preparation. This is important for studying and analyzing disease states in whole-body zebrafish.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Juhi Samal, Tana V. Palomino, Judy Chen, David C. Muddiman, Tatiana Segura
Summary: N-linked glycosylation is a complex protein modification that plays a role in cellular signaling and metabolism. Aberrant protein glycosylation is a characteristic feature of many diseases. Spatial profiling of N-glycans through imaging on tissue sections can be used for disease diagnosis. Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) is a sensitive technique that can be used for mass spectrometry imaging.
ANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
Seth M. Eisenberg, Kevan T. Knizner, David C. Muddiman
Summary: Mass spectrometry imaging (MSI) is a technique for measuring and visualizing the spatial distribution of ions in a sample. METASPACE is commonly used for annotation in high-resolution, accurate mass imaging data, but its reported confidence scores often do not accurately reflect the confidence level. The metabolite annotation confidence score (MACS) is an alternative system based on fundamental metrics to generate values that reflect the confidence of an annotation in HRAM-MSI data.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Alena N. Joignant, Morgan M. Ritter, Kevan T. Knizner, Kenneth P. Garrard, Seth W. Kullman, David C. Muddiman
Summary: This study proposes a novel method of mass spectrometry imaging (MSI) to reduce the acquisition time of MSI data using nested regions of interest (nROIs). By utilizing nROIs, a smaller region of interest can be imaged at higher spatial resolution nested within a larger region of interest at lower spatial resolution, conserving maximal spatial and chemical information while decreasing acquisition time. The nROI method was characterized on mouse liver and applied to top-hat MSI of zebrafish, resulting in significant improvements in acquisition time and spatial detail. The nROI method can be applied to any method where acquiring larger high-resolution ROIs poses a practical challenge.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)
Article
Biochemical Research Methods
Alena N. Joignant, Kevan T. Knizner, Ying Xi, David C. Muddiman
Summary: This study establishes an optimal sample thickness for IR-MALDESI-MSI at around 7 micrometers, as analyzing thicker tissue sections (>10 μm) results in lower ion abundance, decreased signal over long analysis times, and more frequent instrument cleaning.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2023)
