title: Spectrophotometric methods for the determination of omeprazole in bulk form and pharmaceutical formulations.
abstract: Four simple and sensitive methods for the assay of omeprazole (OMZ) were developed. These methods are based on the formation of colored species by treating OMZ with 3-methyl-2-benzothiazolinone hydrazone (MBTH) following oxidation with ferric chloride (method A) or m-aminophenol following oxidation with chloramine-T (CAT) (method B) or Folin-Ciocalteau reagent (FC) (method D), or by oxidizing OMZ with excess N-bromosuccinimide (NBS) and determining the consumed NBS with a decrease in color intensity of Celestine blue (CB) (method C). All variables have been optimized. Regression analysis of Beer's plots showed good correlation in the concentration range of 1.0-10, 2.0-32, 0.4-2.4 and 0.8-10 mug ml(-1) for methods A, B, C and D, respectively. No interference was observed for formulation additives and the validity of each method was tested by analysing capsules containing OMZ. Recoveries were 98.7-100.1%.
authors.affiliation: Foods and Drugs Laboratories, School of Chemistry, Andhra University, Visakhapatnam 530 003, India.
authors.forename: C S
authors.initials: CS
authors.lastname: Sastry
authors.forename: P Y
authors.initials: PY
authors.lastname: Naidu
authors.forename: S S
authors.initials: SS
authors.lastname: Murty