Smart Micro- and Nanostructured Hydrogels for Biomedical Applications Synthesized Via Pcµcp
Hariharasudhan D. Chirra, Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506, J. Zach Hilt, Chemical & Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506, and Dipti Biswal, Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506.
Surfaces that are spatially functionalized with intelligent hydrogels, especially at the micro- and nanoscale, are of high interest in the diagnostic and therapeutic fields. Though conventional methods of the semiconductor industry have been successfully employed for the patterning of hydrogels in devices, methods for fabricating precise 3-D patterns of hydrogels at the micro- and nanoscale over material surfaces are limited. Herein, polymerization controlled by micro contact printing (PCμCP) was applied to synthesize a controlled array of environmentally responsive hydrogels (e.g., N-isopropylacrylamide) over material surfaces. XY control of the hydrogels was achieved using microcontact printing, and the Z/thickness control was achieved using a variety of polymerization techniques such as UV photopolymerization and atom transfer radical polymerization (ATRP). The controlled growth and the responsive behavior of the hydrogels to external stimuli were characterized using optical microscopy, fourier transform infrared (FTIR) imaging, atomic force microscopy (AFM), and scanning electron microscopy (SEM). Using PCμCP based techniques; it is possible to synthesize controlled responsive hydrogels over various surfaces for potential applications in the biomedical field.