A fluorescence method for the determination of venlafaxine hydrochloride

In this study, fluorescence quenching of acridine orange was observed when effective energy transfer occurred between alizarin red and acridine orange under aqueous conditions at a pH of 6.8. However, the quenched fluorescence in this aqueous solution could be partially recovered with the addition of an appropriate amount of venlafaxine hydrochloride. The recovery of fluorescence intensity had a good linear relationship with the amount of added venlafaxine hydrochloride. Based on this, a novel fluorescence recovery method for the determination of venlafaxine hydrochloride was established. The experimental results showed that under the optimal conditions, the linear range of this method was 3.49-31.4 mg L-1, the detection limit was 1.65 mg L-1, and the precision was 1.16%. The method was used for the determination of venlafaxine hydrochloride in sustained-release tablets and capsules with satisfactory results, and the recoveries were in the range of 95.5-105%.