Chromatographic detection of captopril using 4-dimethylaminobenzaldehyde as spray reagent.

Thin layer chromatographic method, using a mixture of acetone:ethanol in the ratio of 9:1 as a developing solvent system, was used to detect captopril in its formulation. The developed chromatogram was sprayed with 4-dimethylaminobenzaldehyde. The product formed by reaction of captopril with 4-dimethylaminobenzaldehyde gave a yellow colour. Rf of captopril is 0.56.