Journal of the Chilean Chemical Society
versión On-line ISSN 0717-9707
SARDANA, SWATI y MASHRU, R.C. SIMULTANEOUS DETERMINATION OF PHENYLEPHRINE HYDROCHLORIDE AND TROPICAMIDE IN OPHTHALMIC DOSAGE FORM WITH THREE RAPID DERIVATIVE SPECTROPHOTOMETRIC METHODS. J. Chil. Chem. Soc. [online]. 2010, vol.55, n.4, pp. 515-518. ISSN 0717-9707. http://dx.doi.org/10.4067/S0717-97072010000400023.
Three spectrophotometric methods have been developed for simultaneous estimation of Phenylephrine hydrochloride (PHE) and Tropicamide (TPC) in their combined dosage form. Method-I: zero-crossing derivative spectrophotometry involves amplitudes measurement of the first derivative spectra of the binary mixture at 284.0nm for PHE and 241.2nm for TPC. Method-II: dual wavelength,which uses the difference in absorbance at 260.8 nm and 268.2 nm for estimation of PHE and 245.4nm and 271.8nm for TPC. Method III: Ratio spectra derivative spectrophotometry, in which division of the absorption spectrum of the binary mixture by a standard spectrum of one of the components and then calculating first derivative amplitudes at 270.8nm for PHE and 240.8nm for TPC . The calibration graph follows Beer's law in the range of 25-125 mg/ml for PHE and 4-20 mg/ml for TPC for all the three methods. The accuracy and precision of the methods were validated statistically.
Palabras clave : Phenylephrine Hydrochloride(PHE); Tropicamide(TPC); zero-crossing derivative spectrophotometry; dual wavelength; Ratio spectra derivative spectrophotometry.