Nikia Lawrence - Virginia State University
Co-Author(s): Dipti Biswal, Virginia State University, VA
Due to their high water content and mechanical resemblance to natural tissues, hydrogels show promising biocompatibility and potential application in microfluidics, tissue engineering, biological and chemical sensors, and other soft matter technologies1. Stimuli responsive hydrogels change their properties of swelling behavior, permeability, and mechanical behavior in response to external stimuli like pH, ionic strength and temperature2. Unique properties can be achieved by incorporation of various nano- and micro-scale materials such as metal particles or biological molecules into the hydrogel matrix. In particular, nanocomposites of responsive hydrogels can exhibit unique dual-responsive properties with capability of actuation at a distance. Temperature responsive hydrogels nanocomposites can be actuated by external stimuli like light or magnetic field and thus can be used as externally actuated drug delivery systems and in microfluidic devices.
Hydrogels nanocomposites embedded with magnetic nanoparticles have been demonstrated as potential candidates for pulsatile drug delivery and soft actuator applications. We synthesized temperature responsive hydrogel nanocomposite matrix by entrapment of magnetic iron oxide nanoparticles in N-isopropylacrylamide (NIPAAm) and polyethylene glycol diacrylate (PEGDA) hydrogel to test the hypothesis that magnetic nanoparticle embedded hydrogels has an affect on drug release within a system. For the formation of magnetic nanoparticles in the crosslinking network, the control hydrogel were immersed in iron salt solution followed by ammonium hydroxide, and this cycles were continued several times in order to incorporated maximum amount of nanoparticles in the hydrogel matrix. The drug release properties of the hydrogel nanocomposites were demonstrated by using pyrocatechol violet (PV) as a model drug. The hydrogel discs with molar ratio of 90:10 NIPAAm-PEGDA were loaded with the drug by imbibition in a 0.1mg/ml PV solution at room temperature for 24h. The infinite dilution method was used for release studies in phosphate buffered solution for the first hour by changing the supernatant solution every 15 min. Our result showed that, the incorporation of magnetic nanoparticles does not affect the release studies of the PV from the hydrogel matrix. Our future research includes the remote controlled release studies of the hydrogel nanocomposites by application of alternating magnetic field.
References: 1. N. A. Peppas; J. Z. Hilt; A. Khademhosseini; R. Langer, “Hydrogels in Biology and Medicine: From Molecular Principles to Bionanotechnology”, Adv. Mater. 2006, 18, 1345.
2. Y-Y Chen, H-C Wu, J-S Sun, G-C Dong, T-W Wang, “Injectable and Thermoresponsive Self-Assembled Nanocomposite Hydrogel for Long-Term Anticancer Drug Delivery”, Langmuir, 2013, 29, 3721.
Funder Acknowledgement(s): National Science Foundation (NSF) HBCU-UP STEM
Faculty Advisor: Diptirani Samantaray,