Spectrofluorimetric quantification of bromazepam using a highly selective optical probe based on Eu3+–bromazepam complex in pharmaceutical and serum samples

A rapid, simple and sensitive spectrofluorimetric method for determination of trace amount of bromazepam is developed. In phosphate buffer of pH 7.4. The bromazepam enhance the luminescence intensity of the Eu3+ ion in Eu3+–bromazepam complex at λex = 390 nm. The produced luminescence intensity of Eu3+–bromazepam complex is in proportion to the concentration of bromazepam. The working range for the determination of bromazepam is 2.3 × 10−8 to 6.2 × 10−7 M with detection limit (LoD) and quantitative detection limit (LoQ) of 3 × 10−9 and 1.2 × 10−8 M, respectively. While, the working range, detection limit (LoD) and quantitative detection limit (LoQ) in case of the quantum yield calculations are 3.7 × 10−8 to 3.4 × 10−7 M with of 3.4 × 10−9 and 9.2 × 10−8 M, respectively. The enhancement mechanism of the luminescence intensity in the Eu3+–bromazepam system has been also explained.