HPLC assay of lidocaine in in vitro dissolution test of the poloxamer 407 gels

Abstract

A simple high performance liquid chromatography method to assay lidocaine hydrochloride in aqueous receiving media, following in vitro release, is presented. Lidocaine hydrochloride was analyzed using a 5 mm LichroCART® RP-18 column (125 × 4 mm i.d.). The mobile phase was acetonitrile: 0.05 M sodium phosphate buffer, pH 6.0 (35:65) and 0.05% of diethylamine at a flow rate of 1 mL/min. The retention time was 7.9 min. Detection was carried out at 210 nm at room temperature (28 °C). The method was found to be linear in the range 1.25 to 25 mg/mL, showing average intra-assay and inter-assay coefficients of variation below 3.5%. The proposed method was validated for linearity, specificity, precision and accuracy and was shown to be useful for the analysis of lidocaine hydrochloride in in vitro release studies.