Multi-wavelength Spectrophotometric Determination of Chlorzoxazone and Paracetamol in Bulk and Capsules

Imad Osman Abu Reid, Abdelrahman Mohamed Tageldin


A simple, cost effective spectrophotometric method has been developed for the simultaneous determination of paracetamol (PAR) and chlorzoxazone (CHL) in bulk and dosage forms. The method permits data to be taken at multiple wavelengths to generate linear plots, from which the concentrations can be determined. The absorbance values of the two analytes were linear with the concentration at the wavelengths taken at 10 nm interval over the range of 230 -300 nm. The accuracy and the precision of the developed method were very good (RSD ? 2%). The validity of the proposed method was confirmed through the statistical comparison of the obtained data with those obtained by a reference method utilizing H-point for the determination of the two actives.


Spectrophotometry, Multi-wavelength, Paracetamol, Chlorzoxazone

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