Development and validation of colorimetric method for the quantitative analysis of kanamycin in bulk and pharmaceutical formulation

The aim of this study was to develop a simple spectrophotometric method for the determination of Kanamycin (KM) in pure bulk form and in its pharmaceutical formulations. Being an amino group containing molecule, KM reacted with ascorbic acid to form a water soluble, purple-pink, 1:1 complex that showed two wavelengths maxima (λmax) at 390 nm and 530 nm. The color was developed after heating for 40 minutes at 100˚ C and remained stable for at least 48 hours. The validity of developed method was tested by analyzing KM under the optimum experimental conditions. Beer’s law was found valid over the concentration range (40-200μg /ml) with an excellent correlation coefficient (less than 0.999). The repeatability and reproducibility results showed a low relative standard deviation values (RSD % u003c 2), which reflected the precision of the developed method. The good percentages added recovery (100.09 ± 0.28 % and 99.98 ± 0.88 %; n=3) at 390nm and 530nm, respectively, reflected the method freedom from interferences.