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Toxicological screening of human plasma by on‐line SPE‐HPLC‐DAD: identification and quantification of acidic and neutral drugs
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Ludmila Mut Thomas Grobosch Torsten Binscheck‐Domaß Wolfgang Frenzel 《Biomedical chromatography : BMC》2016,30(3):343-362
A multi‐analyte screening method for the quantification of 50 acidic/neutral drugs in human plasma based on on‐line solid‐phase extraction (SPE)–HPLC with photodiode array detection (DAD) was developed, validated and applied for clinical investigation. Acetone and methanol for protein precipitation, three different SPE materials (two electro‐neutral, one strong anion‐exchange, one weak cation‐exchange) for on‐line extraction, five HPLC‐columns [one C18 (GeminiNX), two phenyl‐hexyl (Gemini C6‐Phenyl, Kinetex Phenyl‐Hexyl) and two pentafluorophenyl (LunaPFP(2), KinetexPFP)] for analytical separation were tested. For sample pre‐treatment, acetone in the ratio 1:2 (plasma:acetone) showed a better baseline and fewer matrix peaks in the chromatogram than methanol. Only the strong anion‐exchanger SPE cartridge (StrataX‐A, pH 6) allowed the extraction of salicylic acid. Analytical separation was carried out on a Gemini C6‐Phenyl column (150 × 4.6 mm, 3 µm) using gradient elution with acetonitrile–water 90:10 (v/v) and phosphate buffer (pH 2.3). Linear calibration curves with correlation coefficients r ≥ 0.9950/0.9910 were obtained for 46/four analytes. Additionally, this method allows the quantification of 23 analytes for therapeutic drug monitoring. Limits of quantitation ranged from 0.1 (amobarbital) to 23 mg/L (salicylic acid). Inter‐/intra‐day precisions of quality control samples (low/high) were better than 13% and accuracy (bias) ranged from ?14 to 10%. A computer‐assisted database was created for automated detection of 223 analytes of toxicological interests. Four cases of multi‐drug intoxications are presented. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Boris A. Trofimov Ludmila A. Oparina Lidiya N. Parshina Marina Ya. Khil’ko Anatolii P. Tantsyrev Galina P. Aleksandrova 《Cellulose (London, England)》2013,20(3):1201-1214
Diverse celluloses including non-mercerized and mercerized ones have been successfully vinylated with acetylene in the superbase catalytic systems MOH/DMSO and MOH/THF (M = Na, K) at 85–140 °C. Depending on the reaction conditions, degree of substitution of the hydroxyl groups by highly reactive polymerazable vinyloxy groups ranges 0.11–1.22, the yields of vinylated celluloses (insoluble in water, but soluble in DMSO) being 41–89 %. Vinylated celluloses are easily decomposed under the action of white rot fungi: Phanerochaete chrysosporium, Trametes versicolor and Trametes hirsutus, and can constitute a basis for the preparation of biodegradable polymer materials (due to polymerization or polyaddition at the vinyloxy group). 相似文献
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Ludmila A. Oparina Oksana V. Vysotskaya Lidiya N. Parshina Nina K. Gusarova Boris A. Trofimov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2087-2093
Under acid- or base-catalyzed conditions, thiols add regio- and chemos-electively either to vinyloxy or methacrylate group of vinyloxyalkyl-methacrylates to give polyfunctional methacrylates or polyfunctional vinyl ethers, respectively. 相似文献
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Chuiko Alexey Philonenko Ludmila Borisevich Anatoly Lozinsky Miron 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The 1-hydroxyethylidene-1,1-bisphosphonic acid (HEDP) (I) reacts with epichlorohydrine (II) and aminoepoxypropanes (III) in water. Optimum pH for the esterefication is 6–7. The reaction completes in 20–30 h on 60°C at this pH and leads to the mixture of the original HEDP with the mono- and diesters. The mixture of di-Na salts of HEDP and the monochloroester (IV) in ratio 1:1.7 was precipitated from the reaction solution on using of the epichlorohydrine (II). This mixture was used for synthesis of aminoesters (VI a,b) unavailable by direct reaction of HEDP with corresponding aminoepoxides. 相似文献
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Michael A. Pudovik Ludmila K. Kibardina Alexander R. Burilov 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):134-138
The reaction of azomethines of pyridoxal or alkoxyfuropyridines with phosphorus acids produces new salt derivatives. 相似文献
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Chuiko Alexey Philonenko Ludmila Borisevich Anatoly Lozinsky Miron 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Heterocyclic derivatives of gem-bisphosphonates exhibit various biological activities. We have found that thiazolium substituted bisphosphonic acids can be obtained by two-step synthesis from amino-bisphosphonates (I). Reaction of (I) with isothiocyanates in alkohol in the presence of triethylamine led to corresponding thioureas (II) obtained as natrium or triethylamonium salts [1]. Further treatment of (II) with α-bromoketones give aminothiazoles (III) with a good yield. As a rule only less hindered nitrogen atom is involved into the cyclization with formation of one from two of possible isomers. 相似文献