A Validated Spectrofluorimetric Method for Determination of Polysorbate 80 from Pharmaceutical Formulation

A simple, rapid and sensitive spectrofluorimetric method has been developed and validated for the determination of the non-ionic surfactant, polysorbate 80, from pharmaceutical formulation. The proposed method is based on a fluorescence enhancement of the probe (eosin B dye) with addition of polysorbate 80. The eosin B concentration was optimised and found to be 4μg/mL. The fluorescence intensity was measured in a diluting solvent, citric acid buffer (pH 4.0) using excitation and emission wavelengths, 545 nm and 580 nm, respectively. The fluorescence intensity was found to be liner over a concentration range of 16-80 μg/mL of polysorbate 80 with a high correlation coefficient (r = 0.9990). The developed method was validated in terms of linearity, precision, accuracy, limit of detection and limit of quantification and specificity. The limit of detection and limit of quantification for polysorbate 80 were found to be 2 μg/mL and 16 μg/mL, respectively. The developed method was successfully applied for the determination of polysorbate 80 in ophthalmic solution and micro emulsion.