RESUMEN
A study of the reaction of BF3-methanol with benzylpenicillin showed that penicillin could be converted to a form suitable for gas-liquid chromatography. This study indicated possible use of the reaction in an analytical method for penicillin, by determining the methyl phenylacetate product. A reaction rate and yield study was conducted using gas-liquid chromatography employing an internal standard for improved measurement accuracy. The reaction gave a relatively constant yield of 70 +/- 2% and was complete in less than 1 minute. Investigations of the identity of side products were conducted using GC/MS, UV, and IR. A variety of products, including penicillenates, penillates, penilloates, and acrylic acid esters, were indicated at very mild reaction conditions.
Asunto(s)
Boranos/análisis , Penicilina G/análisis , Fenómenos Químicos , Química Física , Cromatografía de Gases/instrumentación , Fluoruros/análisis , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Metanol/análisis , Penicilinas/análisis , Fenilacetatos , Factores de TiempoRESUMEN
A gas-liquid chromatographic (GLC) method is described for the determination of diethylstilbestrol (DES) in molasses-based liquid feed supplements, using dienestrol diacetate as the internal standard. A sample equivalent to 110 mug DES was diluted, acidified with dilute sulfuric acid, extracted with chloroform, and subjected to basic sodium acetate cleanup. The bis-(trimethylsilyl) acetamide derivative was prepared and determined by GLC. Interfering peaks and/or low recoveries were found to be related to emulsions and the procedure incorporates centrifugation to minimize these.