Tailored Polypeptide Star Copolymers for 3D Printing of Bacterial Composites Via Direct Ink Writing. Issue 3 (11th December 2022)

• Record Type: Journal Article
• Authors: Murphy, Robert D.; Garcia, Ronnie V.; Oh, Seung J.; Wood, Tanner J.; Jo, Kyoo D.; Read de Alaniz, Javier; Perkins, Ed; Hawker, Craig J.
• Is Part Of: Advanced materials. Volume 35:Issue 3(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-11
• Subjects: 3D printing -- additive manufacturing -- block copolymers -- hydrogels -- peptides; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202207542
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Hydrogels hold much promise for 3D printing of functional living materials; however, challenges remain in tailoring mechanical robustness as well as biological performance. In addressing this challenge, the modular synthesis of functional hydrogels from 3‐arm diblock copolypeptide stars composed of an inner poly(l ‐glutamate) domain and outer poly(l ‐tyrosine) or poly(l ‐valine) blocks is described. Physical crosslinking due to ß‐sheet assembly of these star block copolymers gives mechanical stability during extrusion printing and the selective incorporation of methacrylate units allows for subsequent photocrosslinking to occur under biocompatible conditions. This permits direct ink writing (DIW) printing of bacteria‐based mixtures leading to 3D objects with high fidelity and excellent bacterial viability. The tunable stiffness of different copolypeptide networks enables control over proliferation and colony formation for embedded Escherichia coli bacteria as demonstrated via isopropyl ß‐d ‐1‐thiogalactopyranoside (IPTG) induction of green fluorescent protein (GFP) expression. This translation of molecular structure to network properties highlights the versatility of these polypeptide hydrogel systems with the combination of writable structures and biological activity illustrating the future potential of these 3D‐printed biocomposites. Abstract : 3D printing of biocompatible hydrogel networks based on the self‐assembly of 3‐arm polypeptide stars permits the additive manufacturing of "living" objects. In this work, the design of the 3‐arm block copolypeptide stars allows for tuning of mechanical properties and printing performance while also directly impacting the proliferation, activity, and colony formation of embedded Escherichia coli .