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 m2/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.

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Microneedle (MN) dressings, with the ability of transdermal drug delivery, have played an essential role in the field of wound healing. However, patients may still feel uncomfortable when sensitive unhealing wounds are pieced by strong needles. Here, inspired by the structure of mosquito mouthparts, which possess a fixation part and a liquid-transferring part, we present a novel MN wound dressing with superfine needle tips, personalized pattern design, programmable needle length, and multiple mechanical strengths for intelligent and painless drug delivery. By simply stretching the silicone rubber (Ecoflex) molds before engraving, superfine MNs can be formed in the restored molds. Meanwhile, by utilizing intelligent image recognition, precise treatment for irregular wounds is achieved. Notably, combined with temperature-responsive N-isopropylacrylamide (NIPAM) hydrogel and inverse opal (IO) photonic crystals (PCs), a controllable drug release system has been achieved on MN dressings. Moreover, the performance of the MN dressing in facilitating wound recovery has been demonstrated by full-thickness skin wounds of a mouse model. These results indicate that novel personalized and programmable MN wound dressings are of considerable value in the field of wound management.

The 62nd residue of glycosyltransferase UGTBL1 was identified as a "hotspot" for glycosylation at 3-OH of resveratrol. Via semi-rational design including structure-guided alanine scanning and saturation mutations, the mutation I62G significantly switched the regioselectivity from 4'-OH to 3-OH of resveratrol and mainly produced polydatin (87.7%), a therapeutic natural product.