RESUMO
A direct and rapid high-performance liquid chromatographic assay for methadone hydrochloride in a flavored oral solution dosage form is described. A syrup sample, one part diluted with three parts of water, is introduced onto a column packed with octadecylsilane bonded on 10 micrometer porous silica gel (reversed phase). A formic acid-ammonium formate-buffered mobile phase is linear programmed with acetonitrile. The absorbance is monitored continuously at 280 or 254 nm, using a flow-through, UV, double-beam photometer. An aqueous methadone hydrochloride solution is used for external standardization. The relative standard deviation was not more than 1.0%. Drug recovery from a syrup base was better than 99.8%.
Assuntos
Metadona/análise , Administração Oral , Cromatografia Líquida de Alta Pressão , Soluções/análiseRESUMO
A method is described for the quantitative determination of morphine, codeine, cryptopine, thebaine, papaverine, and narcotine in opium by high-performance liquid chromatography. The alkaloids are isolated from a dilute acid extract by adsorption on an Amberlite XAD-2 resin column and eluted first with methanol and then with chloroform-methanol (3+1). After solvent removal by reduced pressure evaporation, the alkaloids are redissolved in chloroform-methanol (3+1). The sample solution, plus brucine as an internal standard, is injected onto a Corasil II column and eluted with hexane that is gradient programmed with a solution of chloroform-methanol-diethylamine (100+300+1). The absorbances of the separated alkaloids are continuously monitored at 254 nm, using a flow-through ultraviolet double-beam photometer.