Abstract

Simple, rapid and economical Spectrophotometric methods, requiring no prior separation, have been developed and validated for the simultaneous estimation of amoxycillin and probenecid. These methods utilize spectrum mode of analysis of the recording spectrophotometer (Shimadzu 160 A). Absorption maxima of probenecid was found at 244 nm and that of amoxycillin at 247 nm. Both drugs show linearity in absorbance in the range of 0-50 μg/ml. Using derivative spectroscopy, estimation of probenecid was carried out in first order with N=6 at 272.2 nm and amoxycillin in third order with N=8 at 282 nm. For two wavelength method, absorbance difference was employed at 252.8 nm and 240.6 nm for probenecid and at 250.2 nm and 237.8 nm for amoxycillin. For both the methods the standard deviation values obtained on repeated analysis were below 1.2 and recovery of added standard drug was between 97-100.5%.