Hydrogels are three-dimensional networks of cross-linked hydrophilic polymers which are capable of absorbing and retaining large amount of water in their porous structures. Hydrogels come in a variety of forms such as micro-particles, bead, fiber and patch. Due to their unique swelling properties, hydrogels have a high potential for use as superdisintegrant in pharmaceutical applications. Superdisintegrant is an essential excipient in an oral solid dosage form to ensure an immediate release of drug and thus a fast onset of the pharmacological effect. Hydrogels are traditionally prepared from synthetic polymers which are non-renewable resources. Environmentally friendly hydrogels prepared from renewable bio-based resources have recently drawn significant attention from both industrial and academic sectors due to their renewability. Cassava starch is an important source of biopolymer in Thailand and becomes the focus of the investigation. 
Researchers have successfully developed a process to prepare hydrogel from cassava starch for application as tablet superdisintegrant. Cassava starch is a favorable choice due to its abundant availability, high purity and ability to undergo the chemical modification to alter the structures and improve the properties. The process employs chemical reaction using citric acid, an edible organic acid, as a crosslinking agent. The proposed process ensured homogeneity of the reaction throughout the product. The developed hydrogel can quickly absorb water and swell very fast without the formation of viscous gel layer which may interfere with the release of the active compound, making it suitable for use as a superdisintegrant in drug tablets. The quick swelling of hydrogel particles exerts a tremendous force within the tablet and causes rapid disintegration, thus enhancing drug dissolution rate and improving its bioavailability. This invention was developed through the collaboration between researchers from BIOTEC, Kasetsart University and Chiang Mai University. It has been granted Thai petty patent (Patent No. 10517) and won the Gold Medal at the 13th Taipei International Invention Show & Technomart (INST 2017) held in Taiwan from 28-30 September 2017.