Preparation of biomimetic gene hydrogel via polymerase chain reaction for cell-free protein expression

Abstract

Deoxyribonucleic acid (DNA) hydrogels, a three-dimensional (3D) network made from DNA chains, have attracted great attention because of its molecular programmability, excellent biocompatibility and wide biomedical applications. Construction of hydrogel incorporating genetic function is still a challenge because of the limitations in available preparation methods. Herein, we develop a polymerase chain reaction (PCR) based strategy to construct gene integrated hydrogel to mimic the biofunction of nucleus zone. DNA primers were chemically modified by methacrylamide, which were used as modular primers in PCR to hybridize with template plasmid DNA, yielding methacrylamide functionalized gene (Acry-gene). Afterwards, Acry-gene was chemically cross-linked and compressed via free radical polymerization of terminal group methacrylamide to form a three-dimensional gene network, namely gene hydrogel. The gene hydrogel retained the genetic function and expressed protein successfully in a cell free protein expression system. This work provides a general approach for the construction of biofunctional gene hydrogel which mimics bioprocesses, showing great potential in biomedicine and biomimetic fields.