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

A ratio-first order derivative-zero crossingUV-Visible(UV-Vis)spectrophotometric methodhas been developed for the simultaneous determination of amoxicillin (Amox), levofloxacin(Levo) and lansoprazole (Lanso). The method was validated for the mixtures of Amox, Levo andLanso in the standard solutions and pharmaceutical tablets. Amox, Levo and Lansosolutionsprepared in MeOH:H2O (50:50 v/v) solventmixturewere used in the measurements. Thecalibration 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 ofthem. The calibration curves were optimized linearly between the concentrations of 1.22-15.0mg/L for Lanso, 0.95-20.0 mg/L for Levo and 3.42-40 mg/L for Amox together with thecorrelation 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-firstorder derivative zero-crossing method wasvalidated with good accuracies as the recoveries of 100.0%, 102.5% and 99.2% and with highprecisions as the RSDs % of 1.37, 2.04 and 2.64 for Amox, Levo and Lanso, respectively. It wasshown that the Amox, Levo and Lanso can be determined simultaneously without any separationin pharmaceutical mixture formulations.