The structure and antiproliferative activity of the inclusion complex of neoandrographolide/β-cyclodextrin.

In the present study, the inclusion complex of neoandrographolide and β-cyclodextrin (β-CD) was studied by experimental and theoretical methods. The inclusion complex of neoandrographolide/β-CD was prepared by the saturated solution method. The equilibrium constant of the inclusion complex was determined by UV -vis spectra. The structure of the complex was characterized by DTA, FT-IR, and molecular modeling techniques. All these results indicated that neoandrographolide could enter the cavity of β-CD to form an inclusion complex, and the neoandrographolide/β-CD inclusion complex exhibited different spectroscopic features and properties from neoandrographolide. The molar rate of the inclusion complex was 1:1. The five-membered lactone ring of the neoandrographolide molecule was inserted into the cavities of β-CD from the wider edge. The calculated equilibrium constant of the complex was 489.9918 mol/L. The in-vitro antiproliferative activity of neoandrographolide was significantly improved through the inclusion complexation process. Taken together, the inclusion complexation process was a successful method that could be used in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]