Automated solid sample dissolution coupled with sugaring-out homogenous liquid-liquid extraction. Application for the analysis of throat lozenge samples

Abstract

A novel automated procedure for analysis of solid samples based on the on-line dissolution of solid sample and sugaring-out reagent in water-acetonitrile mixture coupled with sugaring-out homogenous liquid-liquid extraction was developed. The procedure was performed in a mixing chamber of a stepwise injection analysis manifold. The performance of the suggested approach was demonstrated by the determination of 2,4-dichlorobenzyl alcohol, amylmetacresol, Yellow Orange S, Azo Rubine and Ponceau 4R in pharmaceutical samples. After phase separation, the upper acetonitrile phase containing 2,4-dichlorobenzyl alcohol, amylmetacresol and lower aqueous phase containing artificial dyes were sequentially analyzed. Under optimal experimental conditions the linear ranges were found to be 0.1–10mgL−1 for 2,4 dichlorobenzyl alcohol, 0.5–50mgL−1 for amylmetacresol, and 1–100mgL−1 for artificial dyes. The sample throughput was 10h−1. The proposed method was successfully applied for the automated analysis of commercial throat lozenges and the analytical results agreed fairly well with the results obtained by reference HPLC-UV method.