PubAg

Main content area

You searched for: Journal Analytica chimica acta Remove constraint Journal: Analytica chimica acta Subject ionization Remove constraint Subject: ionization Subject derivatization Remove constraint Subject: derivatization Text Availability Citation in PubAg Remove constraint Text Availability: Citation in PubAg
Start Over

Search

26  Search Results

1 - 26 of 26
Number of results to display per page

Search Results

1. Derivatization enhanced separation and sensitivity of long chain-free fatty acids: Application to asthma using targeted and non-targeted liquid chromatography-mass spectrometry approach

Author:
Bian, Xiqing; Sun, Baoqing; Zheng, Peiyan; Li, Na; Wu, Jian-Lin
Source:
Analytica chimica acta 2017 v.989 pp. 59-70
ISSN:
0003-2670
Subject:
ambient temperature; analytical chemistry; asthma; bioactive properties; deoxycholic acid; derivatization; detection limit; dodecanoic acid; eicosapentaenoic acid; free fatty acids; humans; hypertension; inflammation; insulin resistance; ionization; liquid chromatography; mass spectrometry; metabolomics; multivariate analysis; palmitic acid; patients; prostaglandins; ursodeoxycholic acid
Abstract:
... Long chain-free fatty acids (LCFFAs) play pivotal roles in various physiological functions, like inflammation, insulin resistance, hypertension, immune cell behavior and other biological activities. However, the detection is obstructed by the low contents, structural diversity, high structural similarity, and matrix interference. Herein, a fast cholamine-derivatization, within 1 min at room temper ...
DOI:
10.1016/j.aca.2017.08.009

2. Stable isotope N-phosphoryl amino acids labeling for quantitative profiling of amine-containing metabolites using liquid chromatography mass spectrometry

Author:
Zhang, Shanshan; Shi, Jinwen; Shan, Changkai; Huang, Chengting; Wu, Yile; Ding, Rong; Xue, Yuhua; Liu, Wen; Zhou, Qiang; Zhao, Yufen; Xu, Pengxiang; Gao, Xiang
Source:
Analytica chimica acta 2017 v.978 pp. 24-34
ISSN:
0003-2670
Subject:
amino acids; analytical chemistry; derivatization; diastereomers; enantiomers; esters; hydrophilicity; hydrophobicity; ionization; liquid chromatography; matrix-assisted laser desorption-ionization mass spectrometry; metabolites; metabolomics; nuclear magnetic resonance spectroscopy; peptides; phosphates; phosphorus; proteomics; stable isotopes; stereoisomerism; urine
Abstract:
... Stable isotope chemical labeling liquid chromatography-mass spectrometry (LC-MS) is a powerful strategy for comprehensive metabolomics profiling, which can improve metabolites coverage and quantitative information for exploration of metabolic regulation in complex biological systems. In the current work, a novel stable isotope N-phosphoryl amino acids labeling strategy (SIPAL) has been successful ...
DOI:
10.1016/j.aca.2017.04.025

3. Coupling of gas chromatography and electrospray ionization high resolution mass spectrometry for the analysis of anabolic steroids as trimethylsilyl derivatives in human urine

Author:
Cha, Eunju; Jeong, Eun Sook; Cha, Sangwon; Lee, Jaeick
Source:
Analytica chimica acta 2017
ISSN:
0003-2670
Subject:
anabolic steroids; analytical chemistry; derivatization; dissociation; formic acid; gas chromatography; humans; ionization; ions; mass spectrometry; methanol; solvents; steroids; urine
Abstract:
... In this study, gas chromatography (GC) was interfaced with high resolution mass spectrometry (HRMS) with electrospray ionization source (ESI) and the relevant parameters were investigated to enhance the ionization efficiency. In GC-ESI, the distances (x-, y- and z) and angle between the ESI needle, GC capillary column and MS orifice were set to 7 (x-distance), 4 (y-distance), and 1 mm (z-distance) ...
DOI:
10.1016/j.aca.2017.01.058

4. Determination of total cyanide in soil by isotope dilution GC/MS following pentafluorobenzyl derivatization

Author:
Campanella, Beatrice; Biancalana, Lorenzo; D'Ulivo, Lucia; Onor, Massimo; Bramanti, Emilia; Mester, Zoltan; Pagliano, Enea
Source:
Analytica chimica acta 2017
ISSN:
0003-2670
Subject:
acetone; analytical chemistry; derivatization; detection limit; digestion; gas chromatography-mass spectrometry; hydrogen cyanide; ionization; isotope dilution technique; phosphoric acid; sodium hydroxide; soil; soil sampling; toxicity
Abstract:
... The high toxicity of cyanide, along with its widespread industrial use, has fuelled interest in the development of analytical methods for its determination in complex matrices. In this study, we propose a novel approach for the measurement of total cyanide in soil samples based on single-step derivatization with pentafluorobenzyl bromide (F5Bn−Br) followed by quantitation with gas chromatography m ...
DOI:
10.1016/j.aca.2017.01.026

5. Development of C60-based labeling reagents for the determination of low-molecular-weight compounds by matrix assisted laser desorption ionization mass (I): Determination of amino acids in microliter biofluids

Author:
Wu, Pin; Xiao, Hua-Ming; Ding, Jun; Deng, Qian-Yun; Zheng, Fang; Feng, Yu-Qi
Source:
Analytica chimica acta 2017
ISSN:
0003-2670
Subject:
amino acids; analytical chemistry; blood serum; cerebrospinal fluid; correlation; derivatization; desorption; detection limit; ionization; mass spectrometry; molecular weight; urine
Abstract:
... Quantification of low molecular weight compounds (<800 Da) using matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI MS) is challenging due to the matrix signal interference at low m/z region and poor reproducibility of MS responses. In this study, a C60 labeling-MALDI MS strategy was proposed for the fast, sensitive and reliable determination of amino acids (AAs) i ...
DOI:
10.1016/j.aca.2017.01.018

6. The 5-azoniaspiro[4.4]nonyl group for improved MS peptide analysis: A novel non-fragmenting ionization tag for mass spectrometric sensitive sequencing of peptides

Author:
Setner, Bartosz; Rudowska, Magdalena; Kluczyk, Alicja; Stefanowicz, Piotr; Szewczuk, Zbigniew
Source:
Analytica chimica acta 2017
ISSN:
0003-2670
Subject:
ammonium; analytical chemistry; bovine serum albumin; derivatization; dissociation; electrospray ionization mass spectrometry; hydrophobicity; ionization; liquid chromatography; models; peptides; tandem mass spectrometry; thiols; ubiquitin
Abstract:
... A novel class of ionization tags, based on 5-azoniaspiro[4.4]nonyl (ASN+) scaffold were designed for improved analysis of peptides by electrospray tandem mass spectrometry (ESI-MS/MS). A new labeling agent, 1-{[3-oxo-3-(pentafluorophenoxy)propyl]carbamoyl}-5-azoniaspiro[4.4]nonane, was developed to react with amine and/or thiol group-containing peptides. The ionization efficiency of peptides resul ...
DOI:
10.1016/j.aca.2017.07.029

7. MALDI-MS analysis of sialylated N-glycan linkage isomers using solid-phase two step derivatization method

Author:
Li, Henghui; Gao, Wenjie; Feng, Xiaojun; Liu, Bi-Feng; Liu, Xin
Source:
Analytica chimica acta 2016 v.924 pp. 77-85
ISSN:
0003-2670
Subject:
derivatization; analytical chemistry; blood serum; humans; lactones; biomarkers; antibodies; drugs; ionization; pharmaceutical industry; amides; byproducts; isomers; esterification; sialic acids; patients; volunteers; mass spectrometry; desorption
Abstract:
... Sialic acids usually locate at the terminal of many glycan structures in either α(2,3) or α(2,6) linkage, playing different roles in various biological and pathological processes. Several linkage specific carboxyl derivatization methods have been reported to discriminate between α(2,3) and α(2,6)-linked sialic acids by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Among ...
DOI:
10.1016/j.aca.2016.04.023

8. Towards metals analysis using corona discharge ionization ion mobility spectrometry

Author:
Jafari, Mohammad T.; Saraji, Mohammad; Sherafatmand, Hossein
Source:
Analytica chimica acta 2016 v.909 pp. 84-90
ISSN:
0003-2670
Subject:
analytical chemistry; carbon tetrachloride; chelating agents; derivatization; detection limit; hydrides; ionization; liquid-phase microextraction; mercury; pH; solvents; spectroscopy; statistical analysis
Abstract:
... For the first time, the capability of corona discharge ionization ion mobility spectrometry (CD-IMS) in the determination of metal complex was evaluated. The extreme simplicity of dispersive liquid–liquid microextraction (DLLME) coupled to the high sensitivity of CD-IMS measurement could make this combination really useful for simple, rapid, and sensitive determination of metals in different sampl ...
DOI:
10.1016/j.aca.2015.12.036

9. Potential of atmospheric pressure chemical ionization source in gas chromatography tandem mass spectrometry for the screening of urinary exogenous androgenic anabolic steroids

Author:
Raro, M.; Portolés, T.; Pitarch, E.; Sancho, J.V.; Hernández, F.; Garrostas, L.; Marcos, J.; Ventura, R.; Segura, J.; Pozo, O.J.
Source:
Analytica chimica acta 2016 v.906 pp. 128-138
ISSN:
0003-2670
Subject:
anabolic steroids; analytical chemistry; atmospheric pressure; derivatization; detection limit; enzymatic hydrolysis; gas chromatography-mass spectrometry; ionization; ions; liquid-liquid extraction; monitoring; screening; tandem mass spectrometry; urine
Abstract:
... The atmospheric pressure chemical ionization (APCI) source for gas chromatography-mass spectrometry analysis has been evaluated for the screening of 16 exogenous androgenic anabolic steroids (AAS) in urine. The sample treatment is based on the strategy currently applied in doping control laboratories i.e. enzymatic hydrolysis, liquid–liquid extraction (LLE) and derivatization to form the trimethyl ...
DOI:
10.1016/j.aca.2015.11.041

10. Profiling and relative quantification of phosphatidylethanolamine based on acetone stable isotope derivatization

Author:
Wang, Xiang; Wei, Fang; Xu, Ji-qu; Lv, Xin; Dong, Xu-yan; Han, Xianlin; Quek, Siew-young; Huang, Feng-hong; Chen, Hong
Source:
Analytica chimica acta 2016 v.902 pp. 142-153
ISSN:
0003-2670
Subject:
acetone; alkylation; analytical chemistry; derivatization; high fat diet; ionization; liver; mass spectrometry; models; phosphatidylethanolamines; qualitative analysis; quantitative analysis; rats; stable isotopes
Abstract:
... Phosphatidylethanolamine (PE) is considered to be one of the pivotal lipids for normal cellular function as well as disease initiation and progression. In this study, a simple, efficient, reliable, and inexpensive method for the qualitative analysis and relative quantification of PE, based on acetone stable isotope derivatization combined with double neutral loss scan-shotgun electrospray ionizati ...
DOI:
10.1016/j.aca.2015.11.003

11. Charged tag founded in N-(1-chloroalkyl)pyridinium quaternization for quantification of fatty aldehydes

Author:
Cao, Yanjing; Guan, Qing; Sun, Tuanqi; Qi, Wanshu; Guo, Yinlong
Source:
Analytica chimica acta 2016
ISSN:
0003-2670
Subject:
aldehydes; analytical chemistry; bubbles; carcinoma; derivatization; detection limit; electrospray ionization mass spectrometry; high performance liquid chromatography; humans; ionization; pyridines; sulfur dioxide; tissues
Abstract:
... N-(1-chloroalkyl)pyridinium quaternization was developed for the derivatization of fatty aldehydes. Differing from common pre-charged reagents, non-charged pyridine and thionyl chloride were designed to add permanently charged tag on aldehydes. Pyridine was far less competitive than charged derivatives in ionization. Thionyl chloride in excess was quenched by deionized water, converting into less ...
DOI:
10.1016/j.aca.2016.05.032

12. Determination of carbohydrates in tobacco by pressurized liquid extraction combined with a novel ultrasound-assisted dispersive liquid–liquid microextraction method

Author:
Cai, Kai; Hu, Deyu; Lei, Bo; Zhao, Huina; Pan, Wenjie; Song, Baoan
Source:
Analytica chimica acta 2015 v.882 pp. 90-100
ISSN:
0003-2670
Subject:
acetates; analytical chemistry; carbohydrates; centrifugation; chloroform; correlation; cultivars; derivatization; detection limit; flue-cured tobacco; gas chromatography; ionization; liquid-phase microextraction; response surface methodology; sodium chloride; ultrasonic treatment
Abstract:
... A novel derivatization-ultrasonic assisted-dispersive liquid–liquid microextraction (UA-DLLME) method for the simultaneous determination of 11 main carbohydrates in tobacco has been developed. The combined method involves pressurized liquid extraction (PLE), derivatization, and UA-DLLME, followed by the analysis of the main carbohydrates with a gas chromatography-flame ionization detector (GC-FID) ...
DOI:
10.1016/j.aca.2015.03.013

13. A new strategy to determine the protein mutation site using matrix-assisted laser desorption ionization in-source decay: Derivatization by ionic liquid

Author:
Guo, Mengzhe; Zhai, Yixing; Guo, Cheng; Liu, Yaqin; Tang, Daoquan; Pan, Yuanjiang
Source:
Analytica chimica acta 2015 v.865 pp. 31-38
ISSN:
0003-2670
Subject:
analytical chemistry; derivatization; desorption; disulfide bonds; ionic liquids; ionization; ions; matrix-assisted laser desorption-ionization mass spectrometry; mutation; peptides; post-translational modification; proteins; thiols
Abstract:
... Matrix-assisted laser desorption ionization (MALDI) time-of-flight mass spectrometry (TOF-MS) can be considered as state of the art in the field of proteins and peptides analysis. In this work, we have designed an ionic liquid derivative strategy to obtain abundant fragment ions in MALDI in-source decay (ISD) and used the analysis of angiogenin with mutation in the fortieth (K40I) as an instance. ...
DOI:
10.1016/j.aca.2015.01.047

14. Biogenic aldehyde determination by reactive paper spray ionization mass spectrometry

Author:
Bag, Soumabha; Hendricks, P.I.; Reynolds, J.C.; Cooks, R.G.
Source:
Analytica chimica acta 2015 v.860 pp. 37-42
ISSN:
0003-2670
Subject:
aminophenols; analytical chemistry; derivatization; detection limit; dissociation; formaldehyde; hydroxybenzaldehyde; ionization; ions; mass spectrometry; paper; phenol; quantitative analysis; spectrometers; statistical analysis
Abstract:
... Ionization of aliphatic and aromatic aldehydes is improved by performing simultaneous chemical derivatization using 4-aminophenol to produce charged iminium ions during paper spray ionization. Accelerated reactions occur in the microdroplets generated during the paper spray ionization event for the tested aldehydes (formaldehyde, n-pentanaldehyde, n-nonanaldehyde, n-decanaldehyde, n-dodecanaldehyd ...
DOI:
10.1016/j.aca.2015.01.007

15. An isotope-labeled chemical derivatization method for the quantitation of short-chain fatty acids in human feces by liquid chromatography–tandem mass spectrometry

Author:
Han, Jun; Lin, Karen; Sequeira, Carita; Borchers, Christoph H.
Source:
Analytica chimica acta 2015 v.854 pp. 86-94
ISSN:
0003-2670
Subject:
analytical chemistry; cecum; colon; derivatization; detection limit; diet; feces; homeostasis; humans; intestinal microorganisms; ionization; liquid chromatography; metabolism; monitoring; noninsulin-dependent diabetes mellitus; patients; quantitative analysis; short chain fatty acids; tandem mass spectrometry
Abstract:
... Short-chain fatty acids (SCFAs) are produced by anaerobic gut microbiota in the large bowel. Qualitative and quantitative measurements of SCFAs in the intestinal tract and the fecal samples are important to understand the complex interplay between diet, gut microbiota and host metabolism homeostasis. To develop a new LC-MS/MS method for sensitive and reliable analysis of SCFAs in human fecal sampl ...
DOI:
10.1016/j.aca.2014.11.015

16. Investigating sub-2μm particle stationary phase supercritical fluid chromatography coupled to mass spectrometry for chemical profiling of chamomile extracts

Author:
Jones, Michael D.; Avula, Bharathi; Wang, Yan-Hong; Lu, Lu; Zhao, Jianping; Avonto, Cristina; Isaac, Giorgis; Meeker, Larry; Yu, Kate; Legido-Quigley, Cristina; Smith, Norman; Khan, Ikhlas A.
Source:
Analytica chimica acta 2014 v.847 pp. 61-72
ISSN:
0003-2670
Subject:
Chamaemelum nobile; Matricaria chamomilla; analytical chemistry; apigenin; chamomile; derivatization; ionization; mass spectrometry; multivariate analysis; principal component analysis; sesquiterpenoid lactones; supercritical fluid chromatography
Abstract:
... Roman and German chamomile are widely used throughout the world. Chamomiles contain a wide variety of active constituents including sesquiterpene lactones. Various extraction techniques were performed on these two types of chamomile. A packed-column supercritical fluid chromatography–mass spectrometry method was designed for the identification of sesquiterpenes and other constituents from chamomil ...
DOI:
10.1016/j.aca.2014.06.031

17. Rapid identification of traditional Chinese herbal medicine by direct analysis in real time (DART) mass spectrometry

Author:
Wang, Yang; Li, Chunmei; Huang, Liang; Liu, Li; Guo, Yunlong; Ma, Li; Liu, Shuying
Source:
Analytica chimica acta 2014 v.845 pp. 70-76
ISSN:
0003-2670
Subject:
Corydalis; Fritillaria thunbergii; alkaloids; analytical chemistry; derivatization; flavonoids; ginsenosides; herbal medicines; ionization; mass spectrometry; rapid methods; temperature
Abstract:
... Direct analysis in real time-mass spectrometry (DART-MS) was employed as a novel fast method to identify traditional Chinese herbal medicine (TCHM). In order to obtain high quality mass spectra, the ionization temperature was optimized for every kind of sample. With minimal or no sample pretreatment, major TCHM components, including alkaloids, flavonoids and some ginsenosides, were directly detect ...
DOI:
10.1016/j.aca.2014.06.014

18. Total microcystins analysis in water using laser diode thermal desorption-atmospheric pressure chemical ionization-tandem mass spectrometry

Author:
Roy-Lachapelle, Audrey; Fayad, Paul B.; Sinotte, Marc; Deblois, Christian; Sauvé, Sébastien
Source:
Analytica chimica acta 2014 v.820 pp. 76-83
ISSN:
0003-2670
Subject:
World Health Organization; analytical chemistry; cost effectiveness; derivatization; detection limit; drinking water; guidelines; ionization; microcystin-LR; oxidation; screening; tandem mass spectrometry; water analysis
Abstract:
... A new approach for the analysis of the cyanobacterial microcystins (MCs) in environmental water matrices has been developed. It offers a cost efficient alternative method for the fast quantification of total MCs using mass spectrometry. This approach permits the quantification of total MCs concentrations without requiring any derivatization or the use of a suite of MCs standards. The oxidation pro ...
DOI:
10.1016/j.aca.2014.02.021

19. On-line coupling of macroporous resin column chromatography with direct analysis in real time mass spectrometry utilizing a surface flowing mode sample holder

Author:
Zeng, Shanshan; Wang, Lu; Chen, Teng; Qu, Haibin
Source:
Analytica chimica acta 2014 v.811 pp. 43-50
ISSN:
0003-2670
Subject:
Panax notoginseng; analytical chemistry; chemical composition; chromatography; derivatization; helium; ionization; mass spectrometry; pharmaceutical industry; porous media; process monitoring; statistical analysis
Abstract:
... A surface flowing mode sample holder was designed as an alternative sampling strategy for direct analysis in real time mass spectrometry (DART-MS). With the sample holder, the on-line coupling of macroporous resin column chromatography with DART-MS was explored and the new system was employed to monitor the column chromatography elution process of Panax notoginseng. The effluent from macroporous r ...
DOI:
10.1016/j.aca.2013.12.014

20. Simultaneous derivatization and air-assisted liquid–liquid microextraction of some aliphatic amines in different aqueous samples followed by gas chromatography-flame ionization detection

Author:
Farajzadeh, Mir Ali; Nouri, Nina
Source:
Analytica chimica acta 2013 v.775 pp. 50-57
ISSN:
0003-2670
Subject:
amines; derivatization; detection limit; gas chromatography; glass; ionization; liquid-phase microextraction; solvents
Abstract:
... The paper presents a new method based on simultaneous derivatization and air-assisted liquid–liquid microextraction (AALLME) for the extraction and preconcentration of some aliphatic amines prior to gas chromatography-flame ionization detection (GC-FID). Primary aliphatic amines are derivatized and extracted simultaneously by a fast reaction with butylchloroformate (derivatization agent/extraction ...
DOI:
10.1016/j.aca.2013.03.004

21. Determination of polycyclic aromatic hydrocarbons and their oxy-, nitro-, and hydroxy-oxidation products

Author:
Cochran, R.E.; Dongari, N.; Jeong, H.; Beránek, J.; Haddadi, S.; Shipp, J.; Kubátová, A.
Source:
Analytica chimica acta 2012 v.740 pp. 93-103
ISSN:
0003-2670
Subject:
air; derivatization; gas chromatography-mass spectrometry; ionization; methane; monitoring; oxidation; particulates; polycyclic aromatic hydrocarbons; smoke; solid phase extraction; temperature
Abstract:
... A sensitive method has been developed for the trace analysis of PAHs and their oxidation products (i.e., nitro-, oxy-, and hydroxy-PAHs) in air particulate matter (PM). Following PM extraction, PAHs, nitro-, oxy-, and hydroxy-PAHs were fractionated using solid phase extraction (SPE) based on their polarities. Gas chromatography–mass spectrometry (GC–MS) conditions were optimized, addressing inject ...
DOI:
10.1016/j.aca.2012.05.050

22. Determination of perfluorocarboxylic acids in water by ion-pair dispersive liquid–liquid microextraction and gas chromatography–tandem mass spectrometry with injection port derivatization

Author:
Liu, Wen-Lin; Ko, Yen-Chen; Hwang, Bao-Huey; Li, Zu-Guang; Yang, Thomas Ching-Cherng; Lee, Maw-Rong
Source:
Analytica chimica acta 2012 v.726 pp. 28-34
ISSN:
0003-2670
Subject:
acids; derivatization; detection limit; gas chromatography; hydrogen; ionization; liquid-phase microextraction; river water; tandem mass spectrometry
Abstract:
... A novel technique for derivatization in a gas chromatograph injection port after a one-step extraction of trace perfluorocarboxylic acids (PFCAs) in water with ion pair formation during dispersive liquid–liquid microextraction (DLLME) was investigated. Tetrabutylammonium hydrogen sulfate (TBAHS) was used as the ion pair reagent. PFCA butyl ester derivatives were formed in the GC injection port and ...
DOI:
10.1016/j.aca.2012.03.019

23. Novel methods for the quantification of (2E)-hexadecenal by liquid chromatography with detection by either ESI QTOF tandem mass spectrometry or fluorescence measurement

Author:
Lüth, Anja; Neuber, Corinna; Kleuser, Burkhard
Source:
Analytica chimica acta 2012 v.722 pp. 70-79
ISSN:
0003-2670
Subject:
derivatization; detection limit; fluorescence; human cell lines; ionization; liquid chromatography; metabolism; quantitative analysis; sphingolipids; tandem mass spectrometry
Abstract:
... Sphingosine-1-phosphate lyase (SPL) is the only known enzyme that irreversibly cleaves sphingosine-1-phosphate (S1P) into phosphoethanolamine and (2E)-hexadecenal during the final step of sphingolipid catabolism. Because S1P is involved in a wide range of physiological and diseased processes, determining the activity of the degrading enzyme is of great interest. Therefore, we developed two procedu ...
DOI:
10.1016/j.aca.2012.01.063

24. Improvement and extension of the application scope for matrix-assisted laser desorption/ionization mass spectrometric analysis-oriented N-alkylpyridinium isotope quaternization

Author:
Wang, Hang; Wang, Haoyang; Zhang, Li; Zhang, Jing; Leng, Jiapeng; Cai, Tingting; Guo, Yinlong
Source:
Analytica chimica acta 2011 v.707 no.1-2 pp. 100-106
ISSN:
0003-2670
Subject:
byproducts; carbohydrates; cholesterol; derivatization; desorption; fatty alcohols; ionization; isotopes; mass spectrometry; screening; solvents; urine
Abstract:
... Based on our previous report on N-alkylpyridinium isotope quaternization (NAPIQ) for the analysis of cholesterol and fatty alcohols, we have further developed the NAPIQ method for wider applications in screening various small compounds. The reaction scope and improvement were investigated via the screening of compounds with different reaction sites. The experimental results showed that the NAPIQ s ...
DOI:
10.1016/j.aca.2011.09.019

25. N-Alkylpyridinium isotope quaternization for matrix-assisted laser desorption/ionization Fourier transform mass spectrometric analysis of cholesterol and fatty alcohols in human hair

Author:
Wang, Hang; Wang, Haoyang; Zhang, Li; Zhang, Jing; Guo, Yinlong
Source:
Analytica chimica acta 2011 v.690 no.1 pp. 1-9
ISSN:
0003-2670
Subject:
amino acids; cations; cholesterol; derivatization; desorption; detection limit; fatty acids; fatty alcohols; humans; ionization; isotopes; mass spectrometry; phenols; pyridines
Abstract:
... Isotope-coded reagents have been developed for labeling of amino acids, phenols and fatty acids, but not for alcohols. In this work, a simple reaction based on direct N-alkylpyridinium isotope quaternization (NAPIQ) was developed for mild derivatization of cholesterol and fatty alcohols. Different from the conventional quaternary reagents with cations on themselves, two simple and charge-neutral r ...
DOI:
10.1016/j.aca.2011.02.017

26. Derivatization of (5R)-hydroxytriptolide from benzylamine to enhance mass spectrometric detection: Application to a Phase I pharmacokinetic study in humans

Author:
Liu, Jia; Chen, Xiaoyan; Zhang, Yifan; Miao, Hong; Liu, Ke; Li, Liang; Zhong, Dafang
Source:
Analytica chimica acta 2011 v.689 no.1 pp. 69-76
ISSN:
0003-2670
Subject:
acetonitrile; ammonium hydroxide; anti-inflammatory activity; clinical trials; derivatization; humans; ionization; liquid chromatography; pH; pharmacokinetics; solvents; tandem mass spectrometry
Abstract:
... (5R)-Hydroxytriptolide, a semisynthetic structural analog of triptolide, exhibits anti-inflammatory and immunosuppressive effect both in vitro and in vivo. The compound is currently undergoing Phase I clinical trials. This work describes the quantification of (5R)-hydroxytriptolide in human plasma based on chemical derivatization from benzylamine. Analysis through liquid chromatography–tandem mass ...
DOI:
10.1016/j.aca.2011.01.016