In-situ sampling of lipids in tissues using a porous membrane microprobe for direct mass spectrometry analysis

Recent advances in on-site mass spectrometry analysis for clinical applications

On-site quantitation of morphine in urine by fast derivatization and miniature mass spectrometry analysis

Deep-lipidotyping by mass spectrometry: recent technical advances and applications

Site-Specific Photochemical Reaction for Improved C=C Location Analysis of Unsaturated Lipids by Ultraviolet Photodissociation

Unraveling the complexity of the lipidome requires the development of novel approaches to facilitate structural identification and characterization of lipid species with isomer-level discrimination. Ultraviolet photodissociation tandem mass spectrometry (UVPD MS/MS) is a promising tool for structure determination of lipids. The sensitivity of UVPD for lipid analysis however is limited mainly due to weak absorption of UV photons by a C=C. Herein, a C=C site-specific derivatization, the Paternò-Büchi (PB) reaction, was used to incorporate a chromophore to the C=C moiety in fatty acyls, leading to significantly improved UVPD efficiency and sensitivity for pinpointing C=C locations. The wavelength-dependent photodissociation of the PB products demonstrated 4-CF3-benzophenone as the best reagent for UVPD in terms of the efficiency of generating C=C diagnostic fragments and simplicity for C=C location assignments. We demonstrated the effectiveness of this approach for the shotgun profiling of C=C location isomers in different lipid classes from complex lipid extracts, highlighting its potential to advancing the identification of the C=C bond locations in unsaturated lipids.

Development of a Miniature Mass Spectrometry System for Point-of-Care Analysis of Lipid Isomers Based on Ozone-Induced Dissociation

Single-cell lipidomics with high structural specificity by mass spectrometry

AbstractSingle-cell analysis is critical to revealing cell-to-cell heterogeneity that would otherwise be lost in ensemble analysis. Detailed lipidome characterization for single cells is still far from mature, especially when considering the highly complex structural diversity of lipids and the limited sample amounts available from a single cell. We report the development of a general strategy enabling single-cell lipidomic analysis with high structural specificity. Cell fixation is applied to retain lipids in the cell during batch treatments prior to single-cell analysis. In addition to tandem mass spectrometry analysis revealing the class and fatty acyl-chain for lipids, batch photochemical derivatization and single-cell droplet treatment are performed to identify the C=C locations and sn-positions of lipids, respectively. Electro-migration combined with droplet-assisted electrospray ionization enables single-cell mass spectrometry analysis with easy operation but high efficiency in sample usage. Four subtypes of human breast cancer cells are correctly classified through quantitative analysis of lipid C=C location or sn-position isomers in ~160 cells. Most importantly, the single-cell deep lipidomics strategy successfully discriminates gefitinib-resistant cells from a population of wild-type human lung cancer cells (HCC827), highlighting its unique capability to promote precision medicine.

Enabling High Structural Specificity to Lipidomics by Coupling Photochemical Derivatization with Tandem Mass Spectrometry

On-Demand Mass Spectrometry Analysis by Miniature Mass Spectrometer

Handheld Mass Spectrometer with Intelligent Adaptability for On-Site and Point-of-Care Analysis

Fast protein analysis enabled by high-temperature hydrolysis

A high-temperature microreaction system is developed for fast and selective hydrolysis of proteins, enabling direct analysis of protein biomarkers by mass spectrometry.

On-site testing of multiple drugs of abuse in urine by a miniature dual-LIT mass spectrometer

Enhanced Phospholipid Isomer Analysis by Online Photochemical Derivatization and RPLC-MS

Single-Cell Mass Spectrometry Analysis of Metabolites Facilitated by Cell Electro-Migration and Electroporation

Targeted Quantification of Peptides Using Miniature Mass Spectrometry

Resolving Modifications on Sphingoid Base and N-Acyl Chain of Sphingomyelin Lipids in Complex Lipid Extracts

Comprehensive Characterization of Phospholipid Isomers in Human Platelets

Lipidome-wide characterization of phosphatidylinositols and phosphatidylglycerols on C C location level

Large-scale lipid analysis with C=C location and sn-position isomer resolving power

AbstractLipids play a pivotal role in biological processes and lipid analysis by mass spectrometry (MS) has significantly advanced lipidomic studies. While the structure specificity of lipid analysis proves to be critical for studying the biological functions of lipids, current mainstream methods for large-scale lipid analysis can only identify the lipid classes and fatty acyl chains, leaving the C=C location and sn-position unidentified. In this study, combining photochemistry and tandem MS we develop a simple but effective workflow to enable large-scale and near-complete lipid structure characterization with a powerful capability of identifying C=C location(s) and sn-position(s) simultaneously. Quantitation of lipid structure isomers at multiple levels of specificity is achieved and different subtypes of human breast cancer cells are successfully discriminated. Remarkably, human lung cancer tissues can only be distinguished from adjacent normal tissues using quantitative results of both lipid C=C location and sn-position isomers.

Rapid and on-site detection of multiple fentanyl compounds by dual-ion trap miniature mass spectrometry system

A lipidomic workflow capable of resolving sn- and CC location isomers of phosphatidylcholines

Large-scale profiling of phosphatidylcholines at the isomer level is achieved by incorporating gas-phase radical-directed fragmentation into an LC-MS/MS workflow.

Polydopamine-Modified Substrates for High-Sensitivity Laser Desorption Ionization Mass Spectrometry Imaging

Online photochemical derivatization enables comprehensive mass spectrometric analysis of unsaturated phospholipid isomers

High-Precision Quantitation of Biofluid Samples Using Direct Mass Spectrometry Analysis

Direct sampling mass spectrometry for clinical analysis

Direct sampling mass spectrometry enables high-performance clinical analysis, such as imaging, drug monitoring and point-of-care testing.

A Polymer Coating Transfer Enrichment Method for Direct Mass Spectrometry Analysis of Lipids in Biofluid Samples

Paper spray ionization mass spectrometry: recent advances and clinical applications

In-capillary microextraction for direct mass spectrometry analysis of biological samples

Shotgun Analysis of Diacylglycerols Enabled by Thiol–ene Click Chemistry

Polydopamine-functionalized poly(ether ether ketone) tube for capillary electrophoresis-mass spectrometry

Fast quantitation of pyrazole fungicides in wine by ambient ionization mass spectrometry

Paper capillary used for fast quantitation of pyrazole fungicides in wines.

Universal biomimetic preparation and immobilization of layered double hydroxide films and adsorption behavior

Ambient Ionization and Miniature Mass Spectrometry Systems for Disease Diagnosis and Therapeutic Monitoring

UV Lamp as a Facile Ozone Source for Structural Analysis of Unsaturated Lipids Via Electrospray Ionization-Mass Spectrometry

Using miniature MS system with automatic blood sampler for preclinical pharmacokinetics study

Aim: Preclinical pharmacokinetic studies are an essential part of modern drug development. In this work, we explored a new solution with onsite analysis using a miniature MS system, which can significantly improve the efficiency of the preclinical study. Materials & methods: A miniature mass spectrometer was used with an automatic blood sampler for onsite quantitation of drug compounds in whole blood samples. Slug-flow microextraction was used to replace the in-lab sample preparation. Results & conclusion: Animal studies were carried out using two drug compounds, using the auto sampler to take blood samples at preprogrammed time points. The miniature MS system was used to obtain drug concentrations, which were subsequently used to calculate the pharmacokinetic parameters.

Layered double hydroxides based ion exchange extraction for high sensitive analysis of non-steroidal anti-inflammatory drugs

An etched polyether ether ketone tube covered with immobilized graphene oxide for online solid phase microextraction of quaternary alkaloids prior to their quantitation by HPLC-MS/MS

Electrochemically modified carbon fiber bundles as selective sorbent for online solid-phase microextraction of sulfonamides

Paper-capillary spray for direct mass spectrometry analysis of biofluid samples

Photochemical Tagging for Quantitation of Unsaturated Fatty Acids by Mass Spectrometry

Mitigation of sensory and motor deficits by acrolein scavenger phenelzine in a rat model of spinal cord contusive injury

Electroosmotic pump-supported molecularly imprinted monolithic column for capillary chromatographic separation of nitrophenol isomers

Growth of metal–organic framework HKUST-1 in capillary using liquid-phase epitaxy for open-tubular capillary electrochromatography and capillary liquid chromatography

Polydopamine-based immobilization of zeolitic imidazolate framework-8 for in-tube solid-phase microextraction

Tyrosinase inhibitor screening in traditional Chinese medicines by electrophoretically mediated microanalysis

Preparation of a novel molecularly imprinted polymer for the highly selective extraction of baicalin

Jacket-free stir bar sorptive extraction with bio-inspired polydopamine-functionalized immobilization of cross-linked polymer on stainless steel wire

Novel molecularly imprinted magnetic nanoparticles for the selective extraction of protoberberine alkaloids in herbs and rat plasma

Selective and sensitive determination of protoberberines by capillary electrophoresis coupled with molecularly imprinted microextraction

Simultaneous determination of three curcuminoids in Curcuma longa L . by high performance liquid chromatography coupled with electrochemical detection

Mussel-inspired polydopamine-assisted hydroxyapatite as the stationary phase for capillary electrochromatography

Graphene/polydopamine-modified polytetrafluoroethylene microtube for the sensitive determination of three active components inFructus Psoraleaeby online solid-phase microextraction with high-performance liquid chromatography

Covalent immobilization of graphene onto stainless steel wire for jacket-free stir bar sorptive extraction

Enhancement of capillary electrochromatographic separation performance by conductive polymer in a layer-by-layer fabricated graphene stationary phase

Sensitive determination of the potential biomarker sarcosine for prostate cancer by LC-MS with N,N ′-dicyclohexylcarbodiimide derivatization

Adsorptive behavior and solid-phase microextraction of bare stainless steel sample loop in high performance liquid chromatography

Polymer Monolith Microextraction Coupled with HPLC for Determination of Jasmonates in Wintersweet Flowers

Preparation of micropipette tip-based molecularly imprinted monolith for selective micro-solid phase extraction of berberine in plasma and urine samples

Determination of Kynurenine and Tryptophan in Human Plasma by Stacking-Micellar Electrokinetic Chromatography

Highly selective extraction of baicalin in natural herbs and medicinal preparations by molecularly imprinted polymer

Analysis of active alkaloids in the Menispermaceae family by nonaqueous capillary electrophoresis-ion trap mass spectrometry

Identification and quantification of active alkaloids in Catharanthus roseus by liquid chromatography–ion trap mass spectrometry

Development of β-cyclodextrin-Modified Silica and Polyporous Polymer Particles for Solid-Phase Extraction of Methyl Jasmonate in Aqueous and Plant Samples

Mussel inspired polydopamine functionalized poly(ether ether ketone) tube for online solid-phase microextraction–high performance liquid chromatography and its application in analysis of protoberberine alkaloids in rat plasma

Universal Multilayer Assemblies of Graphene in Chemically Resistant Microtubes for Microextraction

A poly (4-vinylpridine-co-ethylene glycol dimethacrylate) monolithic concentrator for in-line concentration-capillary electrophoresis analysis of phenols in water samples

Identification and quantification of oleanolic acid and ursolic acid in Chinese herbs by liquid chromatography-ion trap mass spectrometry

Simultaneous determination of vinblastine and its monomeric precursors vindoline and catharanthine in Catharanthus roseus by capillary electrophoresis-mass spectrometry

Simultaneous Separation of Four Metal Ions by CE Using Bis(2-Pyridylmethyl) (8-Pyridylmethyloxy-Quinoline-2-Methyl)Amine as Chelating Agent