(124h) Modelling The Drug Release In pH-Senitive Hydrogels Based On Maa-Co-Hema

pH-sensitive hydrogels offer great potential in a number of areas, including in sensor technologies [1], micro-fluidics [2], medical device technology [3] and as intelligent drug delivery vehicles [4]. However, a good deal is still unknown with regard to how the underlying structure of these materials governs behaviour (transport coefficients being especially sensitive to structural changes). In this work, we investigate pH-sensitive hydrogel matrices based on MAA-co-HEMA, synthesized by free radical polymerization using benzoyl peroxide as an initiator. Hydrogel samples were generated with varying composition and cross-linking density (EGDMA) and characterized using a variety of techniques including AFM, SEM, FT-IR spectroscopy and density (helium pyknometer) measurements. The influence of hydrogel composition on drug release profiles were measured for model drugs Nalidixic Acid and Quinine Sulphate. Resulting drug release profiles (including transport coefficients) are modeled using a finite element computational method, which takes account of the swelling behavior of the hydrogel matrix at different matrix compositions under the influence of the pH of the surrounding solution.

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