Spectrophotometric and Chemometric Methods for Simultaneous Determination of Antazoline and Naphazoline in Pharmaceutical Eye Drops

Two multivariate calibration prediction algorithms, principal component regression (PCR) and partial least squares (PLS), were applied to the spectrophotometric multi-component analysis of a drug containing antazoline hydrochloride (AN) and naphazoline hydrochloride (NP) without any chemical separation procedure. The absorbance data matrix was obtained by measuring the absorbance in the range of 200–400 nm at 1 nm intervals. Additionally, the optimum number of components for PCR and PLS analysis were determined. A series of synthetic solutions containing different concentrations of AN and NP were used to check the prediction ability of the PCR and PLS. The proposed methods were validated for their accuracy and precision, and they were successfully applied for the assay of AN and NP in a commercial pharmaceutical product. The average %recovery values were 103.2 ± 2.3 for AN and 100.8 ± 3.3 for NP in case of PCR, and 104.9 ± 0.73 and 101.8±3.5 for AN and NP, respectively, in case of PLS. No interferences were observed from the common excipients usually used. The results of the proposed methods were compared with those obtained using the reference HPLC method, and excellent agreement was obtained.