Polyacrylamide Photo-responsive Hydrogels and Its Application in Cell Biology

Abstract

In the past decades, tissue engineering (TE) has begun to emerge as a new and efficient approach towards wound healing and disease recovery. Recently, "smart materials", such as those which incorporate photo-switchable and pH sensitive components, have started to be applied in cell biology.We aimed to devise a controllable biocompatible polymer substrate with photo-switchable units that enable the polymer network properties to be altered between two different states. These materials can be used for producing hydrogels for cell migration studies. Here, responses of cells to mechanical properties of the hydrogel can be examined by culturing stem cells or fibroblasts on an extracellular matrix-coated hydrogel substrate that allows the flexibility to be varied while maintaining a constant chemical environment. By comparing cell culture on rigid substrates with those on this soft matter surfaces, cells are expected to display different surface adhesion and migration patterns.In this project, a range of polyacrylamide hydrogels with azobenzene-based crosslinkers, which enable the properties of the gel to be affected by photoirradiation, were produced and tested. The physical properties of the prepared hydrogels were tested before and after irradiation with light. To demonstrate the suitability of these materials for cell culture, fibroblasts were cultured on fibronectin-coated hydrogels. The cells cultured exhibited excellent viability and indicated the material was non-cytotoxic. Furthermore, after photoirradiation of a portion of the gel surface, seeded fibroblasts were observed to migrate to the softer region of the hydrogel. Those cells remaining on the softer area also appeared to exhibit different cell shapes.

Date of Award	1 Aug 2015
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Lu Shin Wong (Supervisor) & Jason Micklefield (Supervisor)