Fluorescence Enhancement of the Doxycycline– Europium Ion–Sodium Dodecyl Sulfonate System and Doxycycline Determination

A new sepctrofluorimetric method for the determination of doxycycline (DC) was developed based on its enhancement of the fluorescence intensity of europium ion in the presence of sodium dodecyl sulfonate(SDS). The mechanism of fluorescence enhancement was studied. Optimum conditions for the determination of DC were also investigated. The linear range was 0.10- 3.00μg/mL. The detection limit was 1.3ng/mL. There was no interference from the excipients normally used in tablet formulations and the serum compositions. The proposed method was successfully applied to the determination of DC in tablets.