Indirect Spectrofluorometric Determination of Enoxaparin Sodium in Pharmaceutical Formulation (Injection) by Ion Association Complex Formation with Acriflavine Dye

Abstract A simple, sensitive and selective spectrofluorometric method has been developed for the determination of enoxaparin sodium in bulk and dosage forms (injection). The method was based on the quantitative quenching effect of enoxaparin on the native fluorescence of acriflavine due to the formation of nonfluorescent supramolecular ion association complex between the studied drug and acriflavine dye in aqueous solution. The decrease of acriflavine fluorescence was observed at 506 nm after excitation at 402 nm. The relationship between quenching fluorescence intensity and concentration of enoxaparin sodium was linear in the range 0.05-20 μg/ml and with correlation coefficient 0.9990 and with LOD and LOQ 0.011 and 0.035 μg/ml respectively. The average recovery was 100.51% and RSD is less than 3.23%. The stoichiometry of enoxaparin to acriflavine was calculated a 1:4. The method was applied successfully to the determination of enoxaparin as injection formulation and the results were in a good agreement with certified value and standard addition procedure.