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Light-mediated Formation and Patterning of Hydrogels for Cell Culture Applications
Published on: September 29, 2016
Interfacial thiol-ene photoclick reactions for forming multilayer hydrogels
Han Shih1, Andrew K Fraser, Chien-Chi Lin
1Department of Biomedical Engineering, Purdue School of Engineering and Technology, Indiana University-Purdue University Indianapolis (IUPUI), 723 W. Michigan St., SL220, Indianapolis, Indiana 46202, USA.
ACS Applied Materials & Interfaces
|February 7, 2013
Summary
Visible light-mediated thiol-ene reactions create multilayer hydrogels. This simple, cytocompatible method enables controlled fabrication for tissue regeneration and drug delivery applications.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Photochemistry
Background:
- Visible light-mediated thiol-ene photoclick reactions offer a versatile platform for hydrogel synthesis.
- Eosin Y, a non-cleavage photoinitiator, has shown potential in photopolymerization but requires thorough characterization for specific applications.
- Developing methods for fabricating complex hydrogel architectures, such as multilayer structures, is crucial for advanced biomedical applications.
Purpose of the Study:
- To characterize the efficacy of eosin Y as a photoinitiator in visible light-mediated thiol-ene photopolymerization.
- To investigate the properties of eosin Y and its reinitiation capabilities within hydrogel systems.
- To develop a novel method for fabricating multilayer step-growth hydrogels using interfacial photoclick reactions and controlled initiator diffusion.
Main Methods:
- In situ photorheometry, gel fraction analysis, and equilibrium swelling ratio measurements were used to evaluate eosin Y's effect on thiol-ene photopolymerization.
- UV-Vis spectrophotometry was employed to assess eosin Y's properties in the presence of macromer species.
- Interfacial hydrogel coating was achieved by exploiting the diffusion of residual eosin Y from preformed hydrogels, followed by visible light-mediated gelation.
Main Results:
- Eosin Y effectively mediated thiol-ene photopolymerization and demonstrated reinitiation capabilities even after initial light exposure.
- The diffusion of eosin Y from preformed hydrogels was successfully utilized to create initiator-free interfacial hydrogel coatings.
- Hydrogel coating thickness could be precisely controlled by adjusting light exposure time, initial eosin Y concentration, or coating solution macromer concentration.
Conclusions:
- Visible light-mediated interfacial thiol-ene photoclick reactions provide a simple and cytocompatible approach for fabricating multilayer hydrogels.
- The developed method avoids cytotoxic components, making it suitable for sensitive biomedical applications.
- This novel gelation chemistry holds significant promise for controlled release of growth factors and encapsulation of cells in tissue engineering.
