Search results for "CAPILLARY ELECTROPHORESIS"

High-throughput capillary electrophoresis frontal analysis method for the study of drug interactions with human serum albumin at near-physiological c…

2004

The application of the short-end capillary injection to capillary electrophoresis frontal analysis (CE-FA) to study the interaction between basic, neutral and acid drugs towards human serum albumin (HSA) at near-physiological conditions is presented. The compounds selected display a wide range of binding affinities and the results obtained were in good agreement with those reported in the literature. An equation for the estimation of the number of primary binding sites and their corresponding affinity constants is developed isolating the experimentally measured variables in just one axis. The proposed CE-FA method to screen drug interactions with HSA under physiological conditions is simple…

Characterization of basic drug–human serum protein interactions by capillary electrophoresis

2006

Drug-protein interactions are determining factors in the therapeutic, pharmacodynamic and toxicological drug properties. The affinity of drugs towards plasmatic proteins is apparently well established in bibliography. Albumin (HSA) especially binds neutral and negatively charged compounds; alpha(1)-acid glycoprotein (AGP) binds many cationic drugs, lipoproteins bind to nonionic and lipophilic drugs and some anionic drugs while globulins interact inappreciably with the majority of drugs. In this paper, the characterization of the interaction between cationic drugs, beta-blockers and phenotiazines towards HSA, AGP, and both HSA + AGP mixtures of proteins under physiological conditions by CE-f…

A novel approach for analysis of oligonucleotide-cisplatin interactions by continuous elution gel electrophoresis coupled to isotope dilution inducti…

2008

In this work we present a novel approach for in vitro studies of cisplatin interactions with 8-mer oligonucleotides. The approach is based on the recently developed coupling of continuous elution gel electrophoresis (GE) to an inductively coupled plasma-sector field mass spectrometer (ICP-SFMS) with the aim of monitoring the interaction process between this cytostatic drug and the nucleotides. In contrast to existing methods, the electrophoretic separation conditions used here allow both the determination of the reaction kinetics in more detail as well as the observation of dominant intermediates. Two different nucleotides sequences have been investigated for comparison purposes, one contai…

Analysis of Rauwolfia Alkaloids Employing Capillary Electrophoresis-Mass Spectrometry

1997

Abstract Capillary electrophoresis-mass spectrometry (CE-MS) was applied to analyse extracts of roots and cell suspension cultures from Rauwolfia serpentina. Most of the alkaloids known to be present in the respective plant material have been resolved via CE and assigned according to their electrospray mass spectra.

Capillary electrophoresis–inductively coupled plasma-mass spectrometry hyphenation for the determination at the nanogram scale of metal affinities an…

2012

Abstract A screening strategy based on hyphenated capillary electrophoresis and inductively coupled plasma mass spectrometry (CE–ICP-MS) was developed to classify phosphorylated ligands according to their europium(III) binding affinity in a hydro-organic medium (sodium formate, pH 3.7, H2O/MeOH 90:10, v/v). Taking advantage of the high sensibility of ICP-MS for detecting phosphorus, this method enabled to assess the affinity of a variety of phosphorylated compounds, including phosphine oxides, thiophosphines, phosphonates, and phosphinates, in less than 1 h and using less than 5 ng of substance. By varying the total europium concentration, complexation constants could be determined accordin…

Analysis of Fungicides in Fruits and Vegetables by Capillary Electrophoresis-Mass Spectrometry

2006

Development of a new multiplex assay for STR typing of telogen hair roots

2006

Abstract We have developed a new strategy in which 10 STR systems plus amelogenin were simultaneously amplified from telogen hair roots with maximal fragment sizes smaller than 270 base pairs. The multiplex includes six STR loci from the European standard set of loci (ESS) for DNA databases (D3S1358, D8S1179, D21S11, THO1, FGA and VWA) as well as four additional STR systems selected for their robustness and short amplicon sizes (D2S1338, D12S391, TPOX and D5S818). Due to the biotinylation of the reverse primers from five STRs systems, these PCR products can be separated from the other six amplicons after PCR amplification. The two sub-multiplexes were then analyzed in two different runs on …

Assays for Detection of Fungal Hallucinogens Such as Psilocybin and Psilocin

2016

Abstract Methods applicable to the detection of hallucinogenic indole compounds, namely psilocybin, psilocin, and related molecules, that have been developed so far for purposes of mycological research, toxicological studies, or forensic investigations are described in this chapter. The most current literature as well as some interesting older publications are cited, providing a historical overview of the subject. Methods of qualitative and quantitative analysis are presented. Additionally, preliminary purification steps and sample treatment before the exact quantitative determination are proposed. The methods described utilized various analytical techniques for the measurement of psilocybi…

Capillary zone electrophoresis of alkaloids

1998

Abstract A comprehensive discussion of important aspects for the analysis of alkaloids by capillary zone electrophoresis (CZE) is given. The influence of structure on the electrophoretic mobility (EM) of indole alkaloids was investigated using a running buffer which is generally applicable to the CZE analysis of alkaloids. The EM, which at the applied conditions was mostly dependent on the size and shape of the solvated analyte ions, was additionally affected by the presence of hydrogen bonds or ion–dipole interactions between protonated and unprotonated alkaloids of the same species. This could be derived from the existence of alkaloidal dimer cluster ions [2M+H]+ when mass spectrometry wa…

General approach for the analysis of various alkaloid classes using capillary electrophoresis and capillary electrophoresis-mass spectrometry

1997

Abstract The analysis of various alkaloid classes employing capillary electrophoresis (CE) and on-line combined CE-mass spectrometry (CE-MS) is described. A CE method is presented for the analysis of alkaloids without derivatisation or purification. The separation of four different groups of alkaloids consisting of monoterpenoid indole alkaloids, protoberberines/benzophenanthridines, β-carboline alkaloids, and isoquinolines from poppy by free zone capillary electrophoresis has been obtained using a 1:1 mixture of 100 mmol 1 −1 ammonium acetate (pH 3.1) and acetonitrile. The influence of alkaloid structure on the electrophoretic mobility is discussed. The CE-MS reconstructed total ion curren…