Controlling the biotechnical properties of synthetic hydrogels allows their application in a wide range of biomedical fields. Cross-linker concentration and monomer mole ratio of poly(2-hydroxyethylmethacrylate-co-N-(2-hydroxypropyl) methacrylamide) [poly(HEMA-co-HPMA)]-based hydrogels were used to control the degree of hydration and water distribution within constructs. Cross-linker concentrations corresponding to 0.1, 0.5, 1.0, and 3.0 mol % tetraethylene glycol (TEGDA) with HEMA/HPMA mole ratios of 1:0 and 4:1, and poly(HEMA-co-HPMA) of cross-linker concentration corresponding to 1.0 mol % TEGDA with a HEMA/HPMA ratio of 1:1 were investigated for their degree of hydration, water distribution, and corresponding physiochemical and mechanical properties. Copolymerization of HEMA and HPMA was confirmed by Fourier-transform infrared spectroscopy. Both cross-linker concentration and chemical composition (HEMA/HPMA) systematically changed the water content and free/bound water distribution in the polymer, which resulted in different biochemical and transport properties. The addition of 20% HPMA (poly(HEMA-co-HPMA) (4:1)) increased total hydration (25%) and glass-transition temperature (9%) and decreased elastic modulus (31%) and nonfreezable bound water (33%) of the hydrogel. Increasing cross-linker concentration resulted in a stiffer hydrogel with less total water but larger nonfreezable water content. Evaluation of poly(HEMA-co-HPMA) (1:1) revealed that further increase of HPMA content increased the degree of hydration by 25% and decreased nonfreezable water content and elastic modulus by 33 and 16%, respectively, compared to that of poly(HEMA-co-HPMA) (4:1). The hydrogel correspondingly had a higher void fraction and rougher freeze-fractured surface. The diffusion-related processes depended more on water distribution within the hydrogel. The poly(HEMA) showed the fastest swelling kinetics with a concomitant burst release profile of fluorescein isothiocyanate–dextran (a drug surrogate), while the compositions containing HPMA showed a sustained release pattern. The biotechnical properties are illustrative examples of key properties that are influenced by the water distribution rather than the absolute water content of hydrogels.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.