Analytical and stability studies on medical cosmetics

Abstract

Two simple and sensitive spectrofluorimetric (method Ι) and spectrophotometric (method ΙΙ) methods have been developed for the determination of some chloride containing toothpastes and panthenol-containing cosmetic preparations respectively. Method Ι is based on quantitative fluorescence quenching of (terbium-salicylate-hexamine ternary complex) by fluoride which could be measured at λem/λex of 547nm/322nm. The ∆Fconcentration plot was rectilinear over the concentration range of 0.5-20 µg/ml. Method ΙΙ depends reaction of panthenol with nitrobenzoxadiazole chloride (NBD-Cl) and measuring the absorbance of the resultant product at 480nm. The absorbance- concentration plot was rectilinear over the concentration range of 2-20 µg/ml