An aptamer-patterned hydrogel for the controlled capture and release of proteins via biorthogonal click chemistry and DNA hybridization

Three-dimensional (3D) bioactive protein-patterned hydrogels provide a more biomimetic environment for cell culture than traditional bioinert scaffolds. However, it has proved difficult to obtain a hydrogel with simultaneously patterned proteins and controlled release at a later stage without inactivating the bioactivity of the fragile proteins. In this study, an aptamer-patterned PEG hydrogel was formed using biorthogonal “click chemistry”. The patterned aptamer could selectively capture the bioactive protein based on the specific affinity between the aptamer and protein, which results in the formation of a patterned protein within the hydrogel. More importantly, by adding the complementary DNA strand (cDNA) of the aptamer, the protein can dissociate from the aptamer at any desired time and concentration due to the DNA hybridization. This aptamer-patterned hydrogel could become a smart and biomimetic 3D micro-environment for controlled delivery of proteins simultaneously in a spatiotemporal manner.