[Preparation of freeze-thaw poly(vinylalcohol) emulsion gel suppository].

Poly (vinylalcohol) (PVA) emulsion gel suppositories were prepared by a given cycle of freezing and thawing. Oil phase and emulsifying agent used were Panacete 800 and a series of Pluronic L-44, respectively. The effects of polymerization degree of PVA on the gel strength and the drug release were investigated. Drug release from PVA emulsion gel suppository was compared with that from a conventional suppository. The structure of gel was observed by using a scanning electron microscope. The gel strength increased when PVA emulsion gel suppository was prepared with Panacete 800 and Pluronic L-44. The drug release of hydrophilic and hydrophobic drugs from the suppository was in agreement with a zero-order release profile. When oil phase was added into PVA gel suppository, PVA fiber became thin and the network of PVA fiber became dense.