title: Derivative-differential UV spectrophotometry and compensation technique for the simultaneous determination of zidovudine and lamivudine in human serum.
abstract: Three new simple, precise, rapid and selective determination methods are described for zidovudine (ZID) and lamivudine (LAM) in human serum and in pharmaceutical formulations. The first method, based on the compensation technique is presented for the derivative spectrophotometric determination of binary mixtures with overlapping spectra. Using ratios of the derivative maxima or the derivative minimum, the exact compensation of either component in the binary mixture and human serum can be achieved, followed by its determination. The second method, differential derivative spectrophotometry, comprised of measurement of the difference absorptivities derivatized in the first order (deltaD1) of a tablet extract in 0.1 N NaOH relative to that of an equimolar solution in methanol at wavelengths of 246 nm and 263 nm, respectively. Neither sample pretreatment nor separation were required. The third method is based on HPLC on a reversed-phase column using a mobile phase of 0.01M sodium dihydrogen phosphate : methanol : acetonitrile (4 : 2 : 3 v/v/v), with detection at 285 nm. Repeatability and reproducibility studies for each compound showed no significant differences at 95% confidence level. The proposed methods were used for the simultaneous determination of the drugs in human serum samples and binary mixtures with good recoveries.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Ankara University, Tandoğan-Ankara, Turkey. erk@pharmacy.ankara.edu.tr
authors.forename: N
authors.initials: N
authors.lastname: Erk
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000032:analysis* / Q000097:blood; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D004338:Drug Combinations; D006801:Humans; D019259:Lamivudine / Q000032:analysis* / Q000097:blood; D008297:Male; D012015:Reference Standards; D013056:Spectrophotometry, Ultraviolet; D013607:Tablets / Q000032:analysis; D015215:Zidovudine / Q000032:analysis* / Q000097:blood
chemical_list: D019380:Anti-HIV Agents; D004338:Drug Combinations; D013607:Tablets; D019259:Lamivudine; D015215:Zidovudine