Year: 2016
Type: article
Abstract: Click chemistries have been investigated for use in numerous biomaterials applications, including drug delivery, tissue engineering, and cell culture. In particular, light-mediated click reactions, such as photoinitiated thiol−ene and thiol−yne reactions, afford spatiotemporal control over material properties and allow the design of systems with a high degree of user-directed property control. Fabrication and modification of hydrogel-based biomaterials using the precision afforded by light and the versatility offered by these thiol−X photoclick chemistries are of growing interest, particularly for the culture of cells within well-defined, biomimetic microenvironments. Here, we describe methods for the photoencapsulation of cells and subsequent photopatterning of biochemical cues within hydrogel matrices using versatile and modular building blocks polymerized by a thiol−ene photoclick reaction. Specifically, an approach is presented for constructing hydrogels from allyloxycarbonyl (Alloc)-functionalized peptide crosslinks and pendant peptide moieties and thiol-functionalized poly(ethylene glycol) (PEG) that rapidly polymerize in the presence of lithium acylphosphinate photoinitiator and cytocompatible doses of long wavelength ultraviolet (UV) light. Facile techniques to visualize photopatterning and quantify the concentration of peptides added are described. Additionally, methods are established for encapsulating cells, specifically human mesenchymal stem cells, and determining their viability and activity. While the formation and initial patterning of thiol-alloc hydrogels are shown here, these techniques broadly may be applied to a number of other light and radical-initiated material systems (e.g., thiol-norbornene, thiol-acrylate) to generate patterned substrates.
DOI: 10.3791/54462-v
Authors: Lisa A. Sawicki, April M. Kloxin
Institution: University of Delaware
Language: English
Subfield: Molecular Medicine
Domain: Life Sciences
Open Access status: bronze
Awards: G1135889967, G2902092823, Discovery of Chemical Probes and Therapeutic Leads, Phase II, G4624648200, G54260337, G545157245, CAREER: Dynamic biomimetic materials with multiscale structural complexity for understanding tissue fibrosis, G8414554082, G8539818882, Molecular Design of Advanced Biomaterials, G9000004818
OpenAlex ID: W4205142578