Topographical heterogeneity in transparent PVA hydrogels studied by AFM

Physically crosslinked poly (vinyl alcohol) (PVA) hydrogels have a wide range of biomedical applications. Transparent and stable PVA hydrogels synthesized by freeze–thawing method are potential candidates to be used as tissue engineering scaffolds provided they exhibit suitable topographical roughness and surface energy. The effect of processing parameters i.e., polymer concentration and number of freeze–thaw cycles on the resulting topography of the freeze–thawed transparent hydrogels has been studied and quantified using non-contact mode of an atomic force microscope (AFM) and image analysis. Simultaneously captured phase contrast images have revealed significant information about morphological changes in the topographical features and crystallinity of the hydrogels. Topographical roughness was found to decrease as a function of number of freeze–thaw cycles.