Ratio - First Order Derivative - Zero Crossing UV-Visible Spectrophotometric Method for Analysis of Amoxicillin, Levofloxacin and Lansoprazole Mixture

Abstract

A ratio - first order derivative - zero crossing UV-Visible (UV-Vis) spectrophotometric method
has been developed for the simultaneous determination of amoxicillin (Amox), levofloxacin
(Levo) and lansoprazole (Lanso). The method was validated for the mixtures of Amox, Levo and
Lanso in the standard solutions and pharmaceutical tablets. Amox, Levo and Lanso solutions
prepared in MeOH:H2O (50:50 v/v) solvent mixture were used in the measurements. The
calibration graphs were prepared at the wavelengths of 248.9, 219.4 and 262.8 nm, respectively,
which were determined as the zero crossing points of the ratio – first order derivative spectra of
them. The calibration curves were optimized linearly between the concentrations of 1.22 - 15.0
mg/L for Lanso, 0.95 - 20.0 mg/L for Levo and 3.42 - 40 mg/L for Amox together with the
correlation coefficients (R2) 0.9996, 0.9993 and 0.9987, respectively. The limits of detection
(LODs) of the improved method were  1.03 mg/L concentration, and the limits of quantification
(LOQs) were  3.42 mg/L. The proposed ratio- first order derivative zero-crossing method was
validated with good accuracies as the recoveries of 100.0%, 102.5% and 99.2% and with high
precisions as the RSDs % of 1.37, 2.04 and 2.64 for Amox, Levo and Lanso, respectively. It was
shown that the Amox, Levo and Lanso can be determined simultaneously without any separation
in pharmaceutical mixture formulations.