N. E. Wagieh, M. A. Hegazy, M. Abdelkawy and E. A. Abdelaleem, “Quantitative Determination of Oxybutynin Hydrochloride by Spectropho-tometry, Chemometry and HPTLC in Presence of Its Degradation Product and Additives in Different Pharmaceutical Dosage Forms,” Talanta, Vol. 80, No. 5, 2010, pp. 2007-2015. doi:10.1016/j.talanta.2009.11.002

has been cited by the following article:

• TITLE: A Comparative Study of the Novel Ratio Difference Method versus Conventional Spectrophotometric Techniques for the Analysis of Binary Mixture with Overlapped Spectra

  AUTHORS: Hayam M. Lotfy, Sarah S. Saleh, Nagiba Y. Hassan, Samia M. Elgizawy

  KEYWORDS: Ratio Difference; Sodium Cromoglicate; Fluorometholone; Binary Mixtures; Spectrophotometry

  JOURNAL NAME: American Journal of Analytical Chemistry, Vol.3 No.11, November 29, 2012

  ABSTRACT: The smart novel ratio difference spectrophotometric method was developed and validated for the determination of a binary mixture of Sodium cromoglicate (SCG) and Fluorometholone (FLU) in presence of benzalkonium chloride without prior separation. The results were compared to that of the conventional methods (dual wavelength and first derivative of ratio spectra). The suggested methods were validated in compliance with the ICH guidelines and were successfully applied for determination of SCG and FLU in their laboratory prepared mixtures and commercial ophthalmic solution. The novel method showed significant advantages over the conventional methods regarding simplicity, minimal data manipulation and maximum reproducibility and robustness; which enabled the analysis of binary mixtures with overlapped spectra for routine quality control testing with quite satisfactory.