Antitumor natural products have many kinds of natural products, including terpenoids, lactones, saponins, alkaloids, polysaccharides, flavonoids and quinones. These natural products mainly show anti-tumor activities such as inhibiting tumor cell proliferation, promoting tumor cell apoptosis, inducing tumor cell differentiation, reversing multidrug resistance of tumor cell, and the stability of telomerase. Unfortunately, most of them are insoluble in water, easy to oxidize, sensitive to light and heat, which limits their clinical application.
Cyclodextrins is a kind of white crystalline compound. It is the general name of cyclic oligosaccharides produced by starch under amylase action. There are mainly alpha-cyclodextrin , beta-cyclodextrin , gamma-cyclodextrin . Among them, beta-cyclodextrin is one of the most important synthetic receptors in supramolecular chemistry because of its low price, low biotoxicity and soluble in water. The role of cyclodextrin in drug preparation is to increase drug stability, solubility, bioavailability, reduce drug irritation and side effects, regulate drug delivery rate and so on, which has attracted wide attention of researchers. Because cyclodextrin has a special structure of hydrophobic and external hydrophilicity, it can selectively bond various guest molecules to form supramolecular inclusion complexes, thus improving the utilization efficiency of drugs.