A simple and sensitive spectrophotometric method is described for the determination of chondroitin sulfate in bulk drug and pharmaceuticals. The proposed method involves strong acid hydrolysis of chondroitin sulfate into monosacchrides by concentrated hydrochloric acid and followed by formation of furfural. The condensation of furfural with resorcinol in the presence of ferric ions yields a yellow-orange coloured complex. This colour has absorption maxima at 435 nm against reagent blank. The absorbance was found to increase linearly with the concentration of the drug and formed the basis for quantification. The calibration graph was linear from 4-32 μg/mL with correlation coefficient was at 0.999. The results presented are statistically validated in accordance with the guidelines provided by ICH. The recovery studies were carried out at three different levels. The precision was good with percentage relative standard deviation (RSD) lower than 2.0%. The Sandellís sensitivity was calculated and was found 0.03782 μg/cm2. The detection limits and quantification limit are found to be 0.2166 μg/mL and 0.6563 μg/mL, respectively. Ruggedness of method was performed and the percentage relative standard deviation (RSD) was found below 2.0%. The proposed method was successfully applied to the determination of chondroitin sulfate in bulk drug and pharnarmaceutical tablet formulation.
Spectrophotometric method, Chondroitin sulfate, Resorcinol