The Spectrofluorometric Determination of 9,10-Phenanthrenequinone

Abstract

Abstract 9,10-Phenanthrenequinone (9,10-PQ) reacts with guanidine in an alkaline medium to form 2-amino-1H-phenanthro[9,10-d]imidazole. The reaction can be used for the fluorometric determination of 9,10-PQ, since the reaction product is fluorescent in an acidic solution. A dimethyl sulfoxide-methanol mixture is suitable as the solvent. A sample solution was allowed to stand for 15 min at room temperature after the additions of guanidine hydrochloride and sodium methoxide solutions, followed by the addition of hydrochloric acid. After the solution had been allowed to stand for 20 min, the fluorescence intensity of the solution was measured at 403 nm with excitation at 363 nm. The fluorescence intensity was stable for at least 8 h. The determination limit of 9,10-PQ was 50 ng.