Effects of Inclusion of Chrysin in Cucurbit[8]uril on Its Stability, Solubility and Antioxidant Potential

The host-guest interaction between cucurbit[8]uril(Q[8]) and chrysin(CHR) has been studied by means of (HNMR)-H-1, mass spectrometry(MS), differential thermal analysis(DTA), and UV-Vis spectrophotometry. The results show that CHR forms a 1:1 inclusion complex with Q[8], with a binding constant of CHR with Q[8] by UV absorption being 5.4X10(6). Phase solubility experiments show a 5.13-fold increase in the solubility of CUR through interaction with Q[8]{c(Q[8])=10(-4) mol/L. A study of the evolution of UV absorption spectra with time shows that Q[8] significantly increases the stability of CHR. The antioxidant activity of CHR-Q[8] has been tested by the ABTS method. The CHR-Q[8] inclusion complex shows a better scavenging effect towards the ABTS radical than CUR, with respective IC50 values of 1.05X10(-6) and 3.07x10(-6) mol/L. In vitro release studies have shown that CHR-Q[8] has a sustained release effect.