Development and validation of an LC method for the determination of six corticosteroids, salicylic acid and parabens in different pharmaceutical formulations

peer reviewedaudience: researcher, professional, student, popularizationMise au point de méthodes d’analyse en vue de l’étude de stabilité des principes actifs dans des formes dermopharmaceutiques dans le cadre de l’établissement d’un Nouveau Formulaire Thérapeutique valid

Développement d’une méthode de dosage automatisé du méthotrexate dans le plasma humain par couplage direct à la chromatographie liquide de l’extraction sur phase solide à empreintes moléculaires

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Separation of aminoglutethimide enantiomers using single and dual cyclodextrin system in capillary electrophoresis

peer reviewedaudience: researcher, professional, student, popularizatio

PPERFORMANCE EVALUATION OF TWO MIPS FOR THE SPE-LC-UV DETERMINATION OF p-[18F]MPPF IN PLASMA

FP6 STRP 516984 MI-lab-on-chi

Separation of isobaric phosphorothioate oligonucleotides in capillary electrophoresis: study of the influence of cationic cyclodextrins on chemo and stereoselectivity

Phosphorothioate (PS) oligonucleotides have drawn more and more attention lately due to their great therapeutic potential. The presence of one (or several) phosphorothioate moiety (ies) improves pharmacokinetic properties but at the same time creates an additional chiral center for each phosphorothioate linkage, and thus diastereomers. It is therefore important to develop analytical strategies to monitor individual species to enable more in-depth investigations. In this study, a PVA coated capillary with a background electrolyte made of 100 mM phosphoric acid adjusted to pH 3.0 with triethanolamine was used. A design of experimental approach provides the optimal conditions for the separation of the eight isobaric diastereomers bearing one phosphorothioate linkage (Mix 1), and the separation of the 12 isobaric diastereomers of a mixture made of oligonucleotides with two phosphorothioate linkages (Mix 2). Remarkably, full separation in Mix 1 could be achieved using a combination of a cationic cyclodextrin (2-hydroxy-3-N,N,N-trimethylamino) propyl-γ-CD chloride, and an anionic cyclodextrin (carboxymethyl-β-cyclodextrin sodium salt), while a second cationic cyclodextrin (2-hydroxy-3-N,N,N-trimethylamino) propyl-β-CD chloride) was required for Mix 2, providing additional selectivity

Automated method for the determination of a new matrix metalloproteinase inhibitor in ovine plasma and serum by coupling of restricted access material for on-line sample clean-up to liquid chromatography

A fully automated liquid chromatographic method was developed for the determination of Ro 28-2653, a new synthetic inhibitor of matrix metalloproteinases (MMPs), in ovine serum and plasma. The method was based on the coupling of a pre-column packed with restricted access material, namely LiChrospher RP-8 ADS (alkyl diol silica), for sample clean-up to an analytical column containing octyl silica stationary phase. One hundred mul of biological sample, to which 2-propanol was automatically added, were injected onto the ADS pre-column, which was then washed with a washing liquid consisting of a mixture of 25 mM phosphate buffer (pH 7.0) and acetonitrile (90: 10; v/v) for 10 min. By rotation of the switching valve, the analyte was then eluted in the back-flush mode with the LC mobile phase composed of a mixture of acetonitrile and 25 mM phosphate buffer (pH 7.0) (57:43; v/v). The UV detection was performed at 395 nm. The main parameters likely to influence the sample preparation technique were investigated. The method was then validated over a concentration range from 17.5 to 1950 ng/mI, the first concentration level corresponding to the lower limit of quantitation. At this concentration level, the mean bias and the R.S.D. value for intermediate precision were -2.4% and 4.2%, respectively. (C) 2004 Elsevier B.V. All rights reserved

DEVELOPMENT AND VALIDATION OF A METHOD FOR THE LC DETERMINATION p-[18F]MPPF IN PLASMA USING A MISPE

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