Colorimetric determination of indolic drugs

A colorimetric method has been developed for the quantitative determination of the rescinnamine, reserpine upto [-10-4M], Yohimbine on complexation with bromothymol blue. The coloured complexes exhibit absorption maxima in the region 415-416 nm. The RSD [Relative Standard Deviation] of the method is 2.02%. The method is simple, easy, rapid and convenient for routine analysis of the indolic drugs