摘要：

Blends between gellan (GL) and gelatin (GE) with various compositions (GL/GE 0/100, 25/75, 50/50, 75/25, 100/0 wt/wt) were produced, as candidate materials for biomedical applications. GL/GE films obtained by casting were subjected to a chemical treatment (CT) in an acidic coagulation bath at a pH promoting ionic interactions between GE and GL. A subsequent dehydrothermal treatment (DHT) was performed, allowing the formation of amide and/or ester bonds between the macromolecules. The effects of blend composition and the type of treatment on the physicochemical properties of the samples were evaluated by scanning electron microscopy, infrared analysis and release tests. Interactions between GE and GL by H-bonding were found to increase with decreasing the GL amount and, for each composition, by applying CT+DHT. Infrared spectra of samples after CT+DHT displayed a new adsorption band which was indicative of ester bonds formation. Release tests evidenced that resistance of GL/GE blends to water dissolution greatly increased after CT+DHT. Mechanical properties of GL/GE samples, determined through stress-strain tests, displayed significant variations as a function of composition. GL/GE two-dimensional scaffolds were fabricated by micromolding (μML), a technique based on the use of a poly-(dimethylsiloxane) (PDMS) mould to create patterns with micro-scale resolution on cast films. The influence of blend composition on the adhesion of primary endothelial cells was studied: GL/GE blends with a high GE content (50 and 75 wt. %) were found to support cells adhesion and proliferation which made them promising candidates for uses in the field of tissue engineering. Coating of GL/GE samples with gelatine enhanced endothelial cell response only for blends containing a high (75 wt%) GE content. Cells tests using endothelial cells were preliminary to future investigations on the potentiality of GL/GE blends as constituent materials for vascular grafts.

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