title: Comparison of three new spectrophotometric methods for simultaneous determination of aspirin and salicylic acid in tablets without separation of pharmaceutical excipients.
abstract: Simultaneous analysis of aspirin (ASA) and salicylic acid (SA) in pharmaceutical tablet preparations was performed by two multicomponent UV-spectrophotometric methods utilizing principal component regression and classical least square algorithm. Additionally, an assay procedure based on second-derivative spectroscopy was developed. The analysis was performed in turbid solutions without separation of interfering excipients. The range, as determined by the second-derivative methods, was 0.2 to 103.2 micrograms/mL for ASA and 0.07 to 44.5 micrograms/mL for SA. Sensitivity for determination of SA was 0.004% of ASA content for the second-derivative method and 0.2% of ASA content for both multicomponent methods. The methods were applied to laboratory mixtures and commercial tablet formulations containing ASA and SA. The advantage of the second-derivative method in determining small amounts of SA in commercial tablet preparations is shown in comparison with a conventional HPLC method. All UV-spectrophotometric methods are rapid, accurate, and reproducible.
authors.affiliation: Department of Pharmaceutical Technology, Eberhard-Karls-University Tübingen, Germany.
authors.forename: B W
authors.initials: BW
authors.lastname: Glombitza
authors.forename: P C
authors.initials: PC
authors.lastname: Schmidt
mesh_terms: D000042:Absorption; D001241:Aspirin / Q000032:analysis* / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D005079:Excipients / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D012459:Salicylates / Q000032:analysis* / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013607:Tablets
chemical_list: D005079:Excipients; D012459:Salicylates; D013607:Tablets; D001241:Aspirin