EarlyView Articles

A validated HPLC‐PDA method for identification and quantification of two bioactive alkaloids, ephedrine and cryptolepine, in different Sida species

Published: Jul 23, 2013

Author(s): Arnab Chatterjee, Satyanshu Kumar, Sunil K. Chattopadhyay

Journal: Biomedical Chromatography

ABSTRACT A simple, rapid, accurate and reproducible reverse‐phase HPLC method has been developed for the identification and quantification of two alkaloids ephedrine and cryptolepine in different extracts of Sida species using photodiode array detection. Baseline separation of the two alkaloids was achieved on a Waters RP‐18 X‐terra column (250 × 4.6 mm, 5 µm) using a solvent system consisting of a mixture of water containing 0.1%...

Development and validation of a stability‐indicating assay including the isolation and characterization of degradation products of metaxalone by LC‐MS

Published: Jul 23, 2013

Author(s): R. Nageswara Rao, Hassan Farah, Prafulla Kumar Sahu, Muthumani Janarthan, Ch. Gangu Naidu

Journal: Biomedical Chromatography

ABSTRACT A stability‐indicating reverse‐phase high‐performance liquid chromatography–mass spectrometric method was developed and validated for the assay of metaxalone through forced degradation under acidic, alkaline, photo, oxidative and peroxide stress conditions. Separation of degradation products was accomplished on a reverse‐phase Phenomenex C18 (250 × 4.6 mm, 5 µm) column thermostated at 25°C using 10 mM aqueous ammonium acetate: methanol...

Rapid and simple LC‐MS/MS screening of 64 novel psychoactive substances using dried blood spots

Published: Jul 19, 2013

Author(s): Lars Ambach, Ana Hernández Redondo, Stefan König, Wolfgang Weinmann

Journal: Drug Testing and Analysis

The range of novel psychoactive substances (NPS) including phenethylamines, cathinones, piperazines, tryptamines, etc. is continuously growing. Therefore, fast and reliable screening methods for these compounds are essential and needed. The use of dried blood spots (DBS) for a fast straightforward approach helps to simplify and shorten sample preparation significantly. DBS were produced from 10 µl of whole blood and extracted offline with...

An unusual case of risperidone instability in a fatality presenting an analytical and interpretative challenge

Published: Jul 19, 2013

Author(s): Kerry Taylor, Simon Elliott

Journal: Drug Testing and Analysis

This paper describes the detection and characterization of unusual metabolite/breakdown products of the anti‐psychotic drug risperidone in post‐mortem blood and urine as part of a toxicological investigation into an unexpected death of a male suffering from paranoid schizophrenia prescribed risperidone and previously paroxetine. Compounds detected in the post‐mortem blood and urine specimens were shown to be benzisoxazole ring scission...

Variability of cannabis potency in the Venice area (Italy): A survey over the period 2010–2012

Published: Jul 19, 2013

Author(s): Luca Zamengo, Giampietro Frison, Chiara Bettin, Rocco Sciarrone

Journal: Drug Testing and Analysis

Cannabis is the most widely used illicit substance globally, with an estimated annual prevalence in 2010 of 2.6–5.0% of the adult population. Concerns have been expressed about increases in the potency of cannabis products. A high tetrahydrocannabinol (THC) content can increase anxiety, depression, and psychotic symptoms, and can increase the risk of dependence and adverse effects on the respiratory and cardiovascular systems in regular...

Expanding analytical possibilities concerning the detection of stanozolol misuse by means of high resolution/high accuracy mass spectrometric detection of stanozolol glucuronides in human sports drug testing

Published: Jul 19, 2013

Author(s): Wilhelm Schänzer, Sven Guddat, Andreas Thomas, Georg Opfermann, Hans Geyer, Mario Thevis

Journal: Drug Testing and Analysis

Anabolic‐androgenic steroids (AAS) represent one of the most frequently detected classes of prohibited substances in doping controls. Due to their long‐lasting beneficial effects on athletic performance, utmost retrospectivity via urine analysis is desirable and accomplished by targeting long‐term metabolites of the respective drugs. In case of stanozolol, a substantial variety of metabolites has enabled the identification of numerous...

Toward sub‐micro‐XRF working at nanometer range using capillary optics

Published: Jul 19, 2013

Author(s): M. Dehlinger, C. Fauquet, F. Jandard, A. Bjeoumikhov, S. Bjeoumikhova, R. Gubzhokov, A. Erko, I. Zizak, D. Pailharey, S. Ferrero, B. Dahmani, D. Tonneau

Journal: X-Ray Spectrometry

Capillary optics are used for X‐ray fluorescence micro‐analysis using the Cu Kα line provided by a rotating anode. The excitation beam is focused using a polycapillary lens on a Co–Ti sample. Cylindrical glass capillaries of various diameters are fitted to the X‐ray detector (Energy Dispersive X‐Ray (EDX) analyzer) and displaced along the irradiated zone of the sample. The fluorescence is studied as a function of capillary position. Good...

LC‐ESI‐MS/MS analysis and pharmacokinetics of jolkinolide B, a potential antitumor active component isolated from Euphorbia fischeriana , in rat plasma

Published: Jul 19, 2013

Author(s): Yang Li, Xiao‐Li Liu, Zhen‐Gang Cai, Si‐Xi Zhang

Journal: Biomedical Chromatography

ABSTRACT A simple, specific and reproducible liquid chromatography–electrospray ionization mass spectrometry was developed and validated for the determination of jolkinolide B, a potential antitumor active component isolated from Euphorbia fischeriana, in rat plasma. Chromatographic separation was achieved on a Venusil MP‐C18 column using an isocratic elution. Jolkinolide B and osthole (internal standard) were monitored by positive electrospray ...

Development of HPLC/fluorescence detection method for chiral resolution of dansylated benzimidazoles derivatives

Published: Jul 19, 2013

Author(s): Emmanuelle Lipka, Julie Charton, Claude Vaccher

Journal: Biomedical Chromatography

ABSTRACT The development of high performance liquid chromatography method on amylose‐based stationary phase (Chiralpak AD) with n‐hexane–2‐propanol (90:10, v/v) as mobile phase allowed the enantioseparation of non‐dansylated and dansylated benzimidazole derivatives, prepared from potent‐AMPK activators, to be achieved. Using both fluorescence and ultraviolet detection, limits of detection and quantification were determined. Fluorescence...

Protein purification by aminosquarylium cyanine dye‐affinity chromatography

Published: Jul 19, 2013

Author(s): M. S. Silva, V. C. Graça, L. V. Reis, P. F. Santos, P. Almeida, J. A. Queiroz, F. Sousa

Journal: Biomedical Chromatography

ABSTRACT The most selective purification method for proteins and other biomolecules is affinity chromatography. This method is based on the unique biological‐based specificity of the biomolecule–ligand interaction and commonly uses biological ligands. However, these ligands may present some drawbacks, mainly because of their cost and lability. Dye‐affinity chromatography overcomes the limitations of biological ligands and is widely...

Screening and long‐term retrospection for psychoactive drugs in presumptive drug‐facilitated crimes using segmented single hairs

Published: Jul 18, 2013

Author(s): Detlef Thieme, Carina Baumer, Hans Sachs, Joerg Teske

Journal: Drug Testing and Analysis

Interaction study of acetylcholinestrase inhibitors on pharmacokinetics of memantine in rat plasma by HPLC‐fluorescence method

Published: Jul 17, 2013

Author(s): Mohamed G. Hassan, Rie Ikeda, Mitsuhiro Wada, Naotaka Kuroda, Hanaa M. Abdel‐Wadood, Horria A. Mohamed, Kenichiro Nakashima

Journal: Biomedical Chromatography

ABSTRACT The present study aims to investigate the possibility of interaction of donepezil (DP) and galantamine (GAL) as acetylcholinestrase inhibitors, on memantine (MT) hydrochloride in rat plasma by HPLC‐fluorescence detection. The separation of MT was achieved within 12 min without interference of DP and GAL on the chromatogram. MT levels in rat plasma with a single administration of MT (2.5 mg/kg, i.p.) and those with a...

Application of a portable XRF spectrometer for classification of potash glass beads unearthed from tombs of Han Dynasty in Guangxi, China

Published: Jul 16, 2013

Author(s): S. Liu, Q. H. Li, Q. Fu, F. X. Gan, Z. M. Xiong

Journal: X-Ray Spectrometry

Thirty‐seven glass beads excavated from the Han Dynasty tombs in Hepu county, Guangxi, China, were analyzed using a portable X‐ray fluorescence (PXRF) spectrometer. Reference sample Corning glass D is used to check precision and accuracy of the equipment for major and minor components. The results of inductively coupled plasma atomic emission spectroscopy and PXRF are compared to evaluate the quality of equipment for trace elements....

The secondary transfer of gunshot residue: an experimental investigation carried out with SEM‐EDX analysis

Published: Jul 16, 2013

Author(s): James French, Ruth Morgan, James Davy

Journal: X-Ray Spectrometry

Gunshot residue (GSR) is produced when a firearm is discharged and is routinely used in the forensic reconstruction of incidents involving firearms. SEM‐EDX with automated detection and analysis software was used to investigate the extent of GSR secondary transfer following the discharge of a firearm. A series of experiments, which mimicked real‐world scenarios, was set up to explore these under‐researched mechanisms. The findings...

Investigation and visualization of resolution theorems in self modeling curve resolution (SMCR) methods

Published: Jul 16, 2013

Author(s): Mahsa Akbari, Hamid Abdollahi

Journal: Journal of Chemometrics

Different approaches have been proposed during recent years to improve the solutions obtained by multivariate curve resolution methods, among them studies on circumstances that result in unique answers are of particular importance. Three so‐called resolution theorems proposed by Rolf Manne comprehensively discuss and survey these conditions. Despite the importance of these theorems, they have not attracted much attention in the...

Brown adipose tissue mapping in rats with combined intermolecular double‐quantum coherence and Dixon water–fat MRI

Published: Jul 15, 2013

Author(s): Jianfeng Bao, Xiaohong Cui, Shuhui Cai, Jianhui Zhong, Congbo Cai, Zhong Chen

Journal: NMR in Biomedicine

Brown adipose tissue (BAT) is a promising therapeutic target in obesity studies. Recently, MRI has been proposed for the mapping of BAT. However, because of the limitation of spatial resolution, similar to the existing positron emission tomography and computed tomography techniques for BAT detection, it fails to distinguish BAT cells when they are mixed with other cells. In this work, a new MRI method is proposed, combining intermolecular...

Determination of chidamide in rat plasma by LC‐MS and its application to pharmacokinetics study

Published: Jul 15, 2013

Author(s): Xianqin Wang, Mengchun Chen, Congcong Wen, Qingwei Zhang, Jianshe Ma

Journal: Biomedical Chromatography

ABSTRACT A sensitive and selective liquid chromatography mass spectrometry method for determination of chidamide in rat plasma was developed. After addition of linezolid as internal standard, protein precipitation by acetonitrile–methanol (9:1, v/v) was used as sample preparation. Chromatographic separation was achieved on a Zorbax SB‐C18 (2.1 × 150 mm, 5 µm) column with acetonitrile–0.1% formic acid as mobile phase with gradient elution. An...

Determination of pseudo‐ginsenoside GQ in human plasma by high performance liquid chromatography–tandem mass spectrometry

Published: Jul 15, 2013

Author(s): Jiping Huo, Hongyun Wang, Pei Hu, Pingya Li, Jinping Liu, Ji Jiang

Journal: Biomedical Chromatography

ABSTRACT A specific, sensitive and rapid method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC‐MS/MS) was developed for the determination of pseudo‐ginsenoside GQ in human plasma. Liquid–liquid extraction was used to isolate the analyte from biological matrix followed by injection of the extracts onto a C8 column with isocratic elution. Detection was carried out on a triple quadrupole tandem mass...

Ultra‐performance liquid‐chromatography with tandem mass spectrometry for rapid analysis of pharmacokinetics, biodistribution and excretion of schisandrin after oral administration of Shengmaisan

Published: Jul 15, 2013

Author(s): Sheng‐wen Lu, Ai‐hua Zhang, Hui Sun, Guang‐li Yan, Ying Han, Xiu‐hong Wu, Xi‐jun Wang

Journal: Biomedical Chromatography

ABSTRACT This study aimed to investigate the in vivo behaviors of the main components in traditional Chinese medicine (TCM) fomulae. The plasma pharmacokinetics, tissue distribution and excretion of the main component‐schisandrin in rats after oral administration of a classical TCM prescription, shengmaisan (SMS), were studied by a developed and validated UPLC‐MS/MS method. The separation of schisandrin was achieved on a UPLC HSS T3...

Diagnosis of coronary heart disease based on ¹ H NMR spectra of human blood plasma using genetic algorithm‐based feature selection

Published: Jul 14, 2013

Author(s): Mahdi Vasighi, Ali Zahraei, Saeed Bagheri, Jamshid Vafaeimanesh

Journal: Journal of Chemometrics

1H NMR spectroscopy was used for the diagnosis of coronary heart disease (CHD) by using human blood plasma samples. One‐dimensional 1H NMR spectra from 29 normal and 35 CHD patients were obtained and investigated. Classification model was built on the basis of linear discriminant analysis in order to establish adequate model for discrimination between pathological and normal samples. Because of high similarity between 1H NMR spectra of...