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Sample Preparation in Quartz Crystal Microbalance Measurements of Protein Adsorption and Polymer Mechanics
Published on: January 22, 2020
Photoresponsive Nanometer-Scale Iron Alginate Hydrogels: A Study of Gel-Sol Transition Using a Quartz Crystal
Miryam Criado-Gonzalez1,2, Laura Corbella1, Bernard Senger3,4
1Instituto de Ciencia y Tecnología de Polímeros (ICTP-CSIC) , c/Juan de la Cierva, 3 , 28006 Madrid , Spain.
Abstract:
Alginate/Fe3+ hydrogels were fabricated on hyaluronic acid (HA) and poly(allylamine hydrochloride) (PAH) multilayers to yield photoresponsive nanometer-scale hydrogels. Light irradiation of the resulting hydrogels induced the photoreduction of "hard" Fe3+ to "soft" Fe2+ cations, leading to changes in the mechanical properties of the hydrogels related to their cross-linking behavior. The buildup and the phototriggered response of the supported alginate hydrogels were followed in situ with a quartz crystal microbalance (QCM) using an open cell allowing light irradiation from an LED source on top of the hydrogel. The results were correlated to the release profiles of folic acid, employed herein as a drug model, obtained from light-irradiated supported iron alginate hydrogels.
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