A fully automatic cross used solid-phase extraction online coupled with ultra-high performance liquid chromatography-tandem mass spectrometry system for the trace analysis of multi-class pharmaceuticals in water samples.

A fully automatic system, which integrated cross used solid-phase extraction with ultra-high performance liquid chromatography-tandem mass spectrometry, was developed and validated for the simultaneous determination of multi-class pharmaceuticals (62 in total) in Milli-Q water, tap water, lake water, and ground water. The online system allowed the cross-utilization of two SPE columns without significant carryover and achieved an automatic, sensitive and fast analysis, requiring about 14 min per analysis. The features of the online system were systematically investigated and the analytical conditions were fully optimized.

Quantitative determination of bioactive proteins in diphtheria tetanus acellular pertussis (DTaP) vaccine by liquid chromatography tandem mass spectrometry.

A liquid chromatography tandem mass spectrometry method (LC-MS/MS) was developed to determine simultaneously the bioactive proteins including pertussis toxin (PT) subunits, filamentous hemagglutinin (FHA), pertactin (PRN) and fimbriae (FIM) in diphtheria, tetanus and acellular pertussis combined vaccine (DTaP). The trypsin digestion conditions were investigated in detail using PT reference to achieve satisfactory results in detection of the peptides on LC-MS/MS with a Bio-C18 column. The performance of the described method was evaluated using reference proteins and the results showed a wide linear range (0.

[Determination of tracheal cytotoxin in pertussis and diphtheria tetanus acellular pertussis vaccines using liquid chromatography-tandem mass spectrometry].

Tracheal cytotoxin (TCT) is a toxic glycopeptide, which contribute to the adverse effects of pertussis toxin (PT) and related vaccines. Although pharmacopeias limit the amount of TCT in PT product, there is no recommended TCT determination method in any pharmacopeia. In this study, a liquid chromatography-tandem mass spectrometry method was developed to determine TCT.

A novel two-dimensional liquid chromatography - Mass spectrometry method for direct drug impurity identification from HPLC eluent containing ion-pairing reagent in mobile phases.

In this study, a novel two dimensional liquid chromatography - mass spectrometry (2D-LC-MS) method with use of a weak anion exchange column between the 1st DLC RP column and the 2nd DLC RP column (RP1-WAX-RP2) was developed and applied to identify drug impurities from MS incompatible mobile phases containing sodium 1-octanesulfonate and non-volatile buffer. The 1st DLC conditions follow exactly the original standard HPLC method recorded in Chinese Pharmacopeia (ChP), European Pharmacopeia (EP) or US Pharmacopeia (USP). An impurity fraction was collected with a built-in sample loop (100 μL) and transferred to the WAX column where 1-octanesulfonate and phosphate were trapped and removed.

Lipidomics study of the protective effects of isosteviol sodium on stroke rats using ultra high-performance supercritical fluid chromatography coupling with ion-trap and time-of-flight tandem mass spectrometry.

Isosteviol sodium (STV-Na) was reported to possess significant protective effects on ischemic stroke in recent years. However, the protective mechanism of STV-Na against stroke was still unclear. In this work, an untargeted lipidomics approach based on the ultra high-performance supercritical fluid chromatography coupling with ion-trap and time-of-flight tandem mass spectrometry (UHSFC-IT-TOF/MS) was employed to investigate the lipid profiles of stroke rats with STV-Na treatment for the first time.

Determination of major aromatic constituents in vanilla using an on-line supercritical fluid extraction coupled with supercritical fluid chromatography.

An on-line supercritical fluid extraction coupled with supercritical fluid chromatography method was developed for the determination of four major aromatic constituents in vanilla. The parameters of supercritical fluid extraction were systematically investigated using single factor optimization experiments and response surface methodology by a Box-Behnken design. The modifier ratio, split ratio, and the extraction temperature and pressure were the major parameters which have significant effects on the extraction.

Pre-column dilution large volume injection ultra-high performance liquid chromatography-tandem mass spectrometry for the analysis of multi-class pesticides in cabbages.

Pre-column dilution large volume injection (PD-LVI), a novel sample injection technique for reverse phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), was developed in this study. The PD-LVI UHPLC-MS/MS system was designed by slightly modifying the commercial UHPLC-MS/MS equipment with a mixer chamber. During the procedure of PD-LVI, sample solution of 200μL was directly carried by the organic mobile phase to the mixer and diluted with the aqueous mobile phase.

An automatic versatile system integrating solid-phase extraction with ultra-high performance liquid chromatography-tandem mass spectrometry using a dual-dilution strategy for direct analysis of auxins in plant extracts.

An automatic versatile system which integrated solid phase extraction (SPE) with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed. Diverse commercial SPE columns can be used under an ambient pressure in this online system realized by a dual-dilution strategy. The first dilution enabled the direct injection of complex samples with minimal pretreatment, and the second dilution realized direct introduction of large volume of strong eluent into the UHPLC column without causing peak broadening or distortion.

[Rapid screening and confirmation of hormones in health foods by high performance liquid chromatography-ion trap-time of flight tandem mass spectrometry].

A method was developed for the screening, confirmation and quantification of 21 hormones including progesterones, etrogens, glucocorticoids and resorcylic acid lactones in health foods by high performance liquid chromatography-ion trap-time of flight tandem mass spectrometry (HPLC-IT-TOF-MS). The analytes in the sample were extracted with acetonitrile containing 1.0% (v/v) acetic acid and the extract was purified with the mixed QuEChERS sorbents.

[Determination of 14 heterocyclic aromatic amines in wine by liquid chromatography-ion trap-time of flight tandem mass spectrometry].

A rapid qualitative and quantitative analytical method was developed for the simultaneous determination of 14 heterocyclic aromatic amines (HAAs) in wine by liquid chromatography-ion trap-time of flight tandem mass spectrometry (LC-IT-TOF MS). HAAs were extracted from the samples by ethyl acetate under alkaline condition. The quantitation was carried out using internal standard method.

Integration of high accuracy N-terminus identification in peptide sequencing and comparative protein analysis via isothiocyanate-based isotope labeling reagent with ESI ion-trap TOF MS.

A multifunctional isothiocyanate-based isotope labeling reagent, [d (0)]-/[d (6)]-4,6-dimethoxy pyrimidine-2-isothiocyanate (DMPITC), has been developed for accurate N-terminus identification in peptide sequencing and comparative protein analysis by ESI Ion-trap TOF mass spectrometry. In contrast with the conventional labeling reagent phenyl isothiocyanate (PITC), DMPITC showed more desirable properties such as rapid labeling, sensitivity enhancement, and facilitating peptide sequencing. More significantly, DMPITC-based labeling strategy possessed the capacity of higher reliable N-terminus identification owning to the high-yield b(1) ion combined with the isotope validation of 6 Da.

Global detection and identification of components from crude and processed traditional Chinese medicine by liquid chromatography connected with hybrid ion trap and time-of-flight-mass spectrometry.

We herein present a chemical profiling method to efficiently process the information acquired by ultra fast liquid chromatography (UFLC)-electrospray ionization source in combination with hybrid ion trap and high-resolution time-of-flight mass spectrometry (UFLC-(ESI)-IT-TOF/MS), facilitating the structural determination of serial components contained in crude or processed traditional Chinese medicine (TCM). Under the optimized UFLC and IT-TOF-MS(n) conditions, over 39 compounds were separated and detected in crude or processed Fructus corni within 25 min. The components were identified by comparing the mass spectra and retention time with reference compounds, or tentatively assigned by elucidating low-energy collision-induced dissociation (CID) fragment ions and matching empirical molecular formula with that of the published compounds.

Characterization and sequence identification of angiotensin II by a novel method involving ultra-fast liquid chromatography assay coupled with matrix-assisted laser desorption/ionization quadrupole ion trap time-of-flight five tandem mass spectrometry analysis.

High-throughput proteomics aims to investigate dynamically changing proteins expressed by a full organism, specific tissue or cellular compartment under certain conditions. High-sensitivity mass spectrometry has gradually become a significant tool for characterizing peptides. Here, we analyzed angiotensin II using ultra-fast liquid chromatography (UFLC) coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS).