ANALYTICAL METHOD BY LIQUID CHROMATOGRAPHY TO ASSAY PIPERINE ASSOCIATED IN NANOEMULSIONS

This work aimed to develop and validate a simple, fast and low cost analytical method for the quantification of the bioactive piperine in nanoemulsions by high performance liquid chromatography with UV detection. Nanoemulsions were prepared by spontaneous emulsification and their physicochemical properties were evaluated. Considering the chromatographic conditions, the mobile phase was composed by methanol:water (70:30, v/v), Gemini® C18 column, and UV detection at 343 nm. The method was linear in the concentration range of 5-50 μg mL-1 (r = 0.9999), specific, precise (repeatability of RSD 0.38 % and intermediate precision of RSD 1.11 %), accurate (101.3 %) and robust. Nanoemulsions showed nanometric droplet size, polidispersity index below 0.11 and negative zeta potential. The piperine content in the samples was 0.99 ± 0.01 mg mL-1. Regarding these features, the analytical conditions proposed in this work were adequate and effective to determine the piperine content in nanoemulsions.