Hydrogel is a polymer system with a three-dimensional network structure containing a large amount of water formed by a simple reaction of one or more monomers, which can be classified into various types according to the structure, cross-linking mode, polymer composition and so on. The application of hydrogel is very wide, covering all aspects of life, its physical properties are conducive to drug delivery, can be better in the local area in accordance with the designed rate of drug release, but also through a variety of functional modifications to achieve responsive on-demand drug release. In recent years, hydrogels have been widely studied as drug delivery carrier materials, and among many marketed products, temperature-sensitive and pH-sensitive hydrogels have a broad market. In addition to this, hydrogels can be combined with other drug delivery technologies, such as for the preparation of microneedles. Hydrogels can also be used to prepare nanoparticles, which have an elastic hydrogel shell and exhibit different cellular uptake behavior than rigid nanoparticles. For subsequent formulation improvement and delivery mode studies to select suitable hydrogel materials as intermediates for transdermal delivery modes, we constructed a hydrogel database based on an extensive literature review. The database covers numerous entries of hydrogel materials such as combination methods, classes, materials, preparation methods, solubility, biocompatibility, mechanical properties, drug loading capacity, drug release, indications, and so on. China's hydrogel-related drug research and development still needs further development, and hydrogel transdermal drug delivery has a broad prospect. Therefore, hydrogel materials with strong drug loading capacity and good drug release effect can be screened directly in this database system as a solid foundation for subsequent research, which can make a certain contribution to drug development.
