Transdermal sustained-release drug delivery system and preparation and application method thereof

The invention provides a formula of a transdermal sustained-release drug delivery system employing water-soluble polymer material as a substrate, a preparation method of the system, and an application of the preparation, wherein the substrate is formed by the mixing of polyvinyl alcohol, gelatin, sodium carboxymethylcellulose, sorbitol, glycerin, sodium polyacrylate, castor oil and water. The substrate is large in drug loading capacity, good in affinity with various drugs including extracts of traditional Chinese medicines and chemical drugs, good in transdermal effect as the drug is sustainedly released in a transdermal manner, air-permeable, high in comfort level while being applied on skin, basically free of skin irritation and hypersensitivity reactions, and can be repeatedly used, thus being an ideal transdermal drug delivery platform. And various kinds of sustained-release transdermal delivery preparation can be prepared by combining with various drugs.