Cell-Free Protein-Synthesis Systems in Printed Matrices: Reagent State, Activation, Transport and Functional Lifetime

Cell-free protein synthesis can be embedded in hydrated matrices so that transcription and translation occur without living cells. For printed or photocurable structures, the critical engineering variables are reagent preservation, activation, water and nutrient transport, product diffusion, matrix compatibility and functional lifetime. This review distinguishes cell-free activity from living-cell viability, defines the material state before and after activation, and proposes a qualification framework for output, spatial distribution, reuse and storage. It does not treat whole-cell biosensing, which is addressed separately in ER-436. ER-435.