STUDY ON THE PREPARATION AND STABILITY OF SOLID DISPERSION OF GOSSYPOL ACETIC ACID—PVP AND ITS SPERMICIDAL ACTIVITY IN VITRO

The solid dispersion of gossypol acitic acid-PVP was prepared at 45℃ and atmospheric pressure using dichloromethane as a solvent. The same result was achieved as using Waller's method, but our improved method was safer and easier than that of Waller's. The mechanism of gossypol acitic acid-PVP solid dispersion was investigated by using X-ray diffraction and ¹HNMR. It was found that hydrogen bonds were present as a binding force between gossypol and PVP. The X-ray diffraction spectra of the solid dispersion showed the typical characteristics of an interstitial solid solution. The dissolution rate of solid dispersion of 1:7 gossypol-PVP is eight times higherthan that of the 1: 4 product reported by Waller. All dissolution curves follow the rule of Q-t^1/2). There is a linear relationship between the proportion of PVP and dissolution rate constant.The effect of different concentrations of gossypol-PVP and gossypol acitic acid-PVP on human spermatozoa were investigated in vitro. The percentage of motility was observed by counting the motile spermatozoa under the microscope. The forwardmotility of human spermatozoa were completely inhibited at a concentration of 10^-3 (0.052%) in 20 seconds. PVP itself has no spermicidal properties.