Tetrasubstituted sulphonated aluminum phthalocyanine-cationic surfactant system for fluorimetric determination of ethanol in alcoholic beverage

A new fluorimetric method was developed for the determination of ethanol in alcoholic beverage. The method is based on the principle that tetrasubstituted sulphonated aluminum phthalocyanine (AlS₄Pc), a red-region fluorescent reagent, is induced to associate in the presence of cationic surfactant, cetyltrimethylammonium bromide (CTMAB), thus its fluorescence is quenched, and then the aggregate is disaggregated by the addition of ethanol and the fluorescence is recovered. This method has a linear determination range of 0.5% ∼ 90.0% (VlV), the detection limit is 0.48% (VIV). The method has been used to determine real alcoholic beverage samples with satisfactory results.