Development and validation of a photometric titration method for the quantitation of sodium chondroitin sulfate (bovine) in Cosequin DS chewable tablet.

A photometric titration method was developed and validated to quantitate sodium chondroitin sulfate in raw materials and Cosequin DS chewable tablet(1). About 0.1% (w/v) cetylpyridinium chloride was used to titrate sodium chondroitin sulfate with photometric indication at wavelength 420 nm. The standard curves for sodium chondroitin sulfate showed linearity (r> or = 0.99) over the selected concentration range from 0.6 to 1.4 mg/ml. The chewable tablet was ground to fine powder and extracted with water and the resulting solutions filtered through a 0.45 microm membrane filter. Recovery between 97 and 103%,. The intra- and inter- day precision as indicated by the relative standard deviation (R.S.D.) were not greater than 0.33 and 0.78%, respectively. The method was found to be specific and with excellent linearity, accuracy and precision and is well suited for the quantitation of sodium chondroitin sulfate in raw material and Cosequin DS chewable tablet.