Complexation of capsaicin with hydroxypropyl-β-cyclodextrin and its analytical application

Fluorescence spectra, H-1 NMR, thermoanalysis and molecular modeling were used to investigate the host-guest inclusion system of hydroxypropyl-beta-cydodextrin (HP beta CD) with capsaicin. Job's plot was employed to confirm a 1:2 host-guest stoichiometry. Phase solubility study indicated that the apparent stability constant was 3.76 x 10(6) M-2. With the enhancing fluorescence of capsaidn complexation with HP beta CD, a spectrofluorirnetric method approach to determine the capsaidn in bulk aqueous solution was developed. Linearity was achieved wide ranges (0.05-60 mu g/mL), with low detection limit of 0.04 mu g/mL, and the relative standard deviation was 1.30%. Application to the analysis of chili powder samples obtained a satisfactory recovery of 99.5-105.6%. (C) 2019 Elsevier B.V. All rights reserved.