Absorbance ratio and derivative spectroscopy methods for the simultaneous estimation of lornoxicam and eperisone in their synthetic mixture.

Abstract

Two simple spectrophotometric methods have been developed for simultaneous estimation of lornoxicam (LXM) and eperisone (EPE) from their synthetic mixture. Method-I involves, formation of Q-absorbance equation at 265 nm (isoabsorptive point) and 290.5 nm (λ_max of Lornoxicam) and Method-II is the first order derivative spectroscopy for the simultaneous estimation of LXM and EPE. The absorbances of the standard solutions have been taken at two wavelengths 264.5 nm (ZCP of Lornoxicam) for EPE and 254 nm (ZCP of Eperisone) for LXM in 0.1N methanolic NaOH. and the linearity ranges between 2-24 µg/mL for both drugs in both methods. The accuracy and precision of the methods are determined and validated statistically. Both the methods show good reproducibility and recovery with RSD less than 2. Both methods are found to be rapid, specific, precise and accurate and can be successfully applied for the routine analysis of lornoxicam and eperisone in bulk and also their combined dosage form.