Determination of Dextromethorphan Hydreobromide in pharmaceutical preparation using derivative spectrophotometric method

Abstract

A simple, sensitive, economic, accurate and precise second (D2) and third (D3) derivative spectrophotometric method has been developed for determination of Dextromethorphan hydrobromide in pharmaceutical preparation. The method obeys Beer’s Law in concentration range of 10-50μg/ml employed for evaluation . The quantitative determination of the drug was carried out using the second and third derivative values by measuring ; peak to base line at  (300 nm ,240 nm and 228 nm for second  derivative) and (303 nm, and 290 nm for third derivative) , peak to peak at ( 300 nm – 240 nm, 240nm – 228nm for second  derivative) and (303 nm-290 nm  for third derivative) and peak area at (313 nm – 290 nm, 256 nm – 230 nm and 232nm -223nm for second derivative) and at (313 nm -298 nm and 297 nm – 281 nm for third derivative) in 1:10% absolute ethanol: distal water . The results of analysis were validated by recovery studies . The recovery and RSD  values was (103.968-97.530 %) and (2.222 – 0.023 %) respectively . The proposed method was applied on syrup formulation (Mini Mond ) .