A Versatile Approach for Enzyme Immobilization Using Chemically Modified 3D-Printed Scaffolds

The tedious preparation procedures and difficulty in free structure formation and recycling have restricted the widespread application of existing enzyme immobilization strategies. Here, we report a novel type of enzyme immobilization strategy utilizing additive manufacturing (also known as 3D printing). The shape and structures of carbon fiber reinforced polylactic acid (C-PLA) scaffolds could be flexibly designed and printed (cube, sphere, and pyramid shapes and microfluidic reactors). After chemical modification with piranha solution, peracetic acid, and a silane coupling agent, the resultant scaffolds achieved a high specific surface area (2.2 m(2)/g, a 3.63-fold increase) with an abundance of surface-active groups. As a proof of concept, four kinds of enzymes (penicillin G acylase (PGA), protease, glycosidase, and lipase) were successfully immobilized on the chemically modified 3D scaffolds. The final yield was 185.6 mM for the reaction catalyzed by PGA, and the final yield of lactosucrose reached 142 g/L for the glycosidase-catalyzed reaction. After 10 cycles, the retention rate of enzymatic activity was 88% for PGA and 92.8% for glycosidase. Thus, tunable 3D-printed enzyme immobilization carriers offer a promising solution to building a simple platform that is low cost and flexible enough to accommodate various enzymes and reactors for industrial applications.