Use of Ethylcellulose-Based Sorbent for Sample Preparation of Multicomponent Drugs Containing Salicylic Acid

UV spectrophotometric determination of salicylic acid in several multicomponent drugs using an ethylcellulose-based sorbent for solid-phase extraction (SPE) for sample preparation was shown to be selective. Selective binding of the analyte to sorbent active sites and stepwise elution successively with purified water and NaOH solution (0.1 M) during SPE eliminated interference of other active pharmaceutical ingredients of multicomponent drugs during identification and quantitation of salicylic acid by UV spectrophotometry. Use of the ethylcellulose sorbent made it possible to improve the metrological parameters and decrease systematic error of the quantitative procedure by an average of 47%.