Photochemical induced fluorescence for the determination of prednisolone and triamcinolone

In the present work, a photochemical derivatization procedure to induce fluorescence from two synthetic glucocorticoids (triamcinolone acetonide and prednisolone) was developed. The procedure consisted of the exposure of analyte acidic solutions to ultraviolet (UV) radiation (254 and 300 nm) in a photochemical reactor at 65 degrees C. Experimental parameters such as type and concentration of the acid, composition of the solvent system, and sample treatment time in the reactor were found to be critical, and, therefore, they were carefully optimized. The intensity of the fluorescence (240/350 nm) and the stability of the signal were, appropriated for analytical purposes. Limits of detection (LD) of 5 and 6 mu g L-1 , respectively, for triamcinolone acetonide and prednisolone were achieved. Linear dynamic range for both analytes extended up to 20 mg L-1 . The spectrofluorimetric determination of prednisolone and triamcinolone acetonide was tested by the analysis of different anti-inflammatory pharmaceutical formulations (tablets, ointment, and veterinary parenteral suspensions). The recoveries achieved were between 95% and 107%. A study to evaluate the effect of potential interferents (polimixine B and benzocaine) on the fluorescence signal of the analytes also has been done.