Investigation on the mechanisms for biocompatibility of chitosan using agarose/chitosan blended hydrogels as a model / 国际生物医学工程杂志

ABSTRACT

ObjectiveTo investigate the possible mechanisms for biocompatibility of chitosan material using agarose/chitosan blended hydrogels as a model.Methods A series of agarose/chitosan blended hydrogels with different chitosan content were prepared by the blending method.The chemical groups of the blended hydrogels were analyzed by the Fourier transform infrared (FTIR) spectroscopy.The blending compatibility between the agarose and chitosan was evaluated with the fluorescein-4-isothiocyanate (FITC) staining method.The charge of the blended hydrogels was determined by the zeta potential measurement.The adsorption of total fetal bovine serum (FBS) proteins and bovine serum albumin (BSA) on the blended hydrogels was measured by the bicinchoninic acid (BCA) method.The adsorption of fibronectin (FN) on the blended hydrogels was measured with ELISA.Cell culture experiment adopted human microvascular endothelial cell line (HMEC-1) as the model.The cytocompatibility was studied by evaluating adhesion,proliferation,and morphology of the cells on the blended hydrogels.Results Characteristic chemical groups of chitosan could be detected in the agarose/chitosan blended hydrogels.The chitosan had a good blending compatibility with the agarose.The amino groups of chitosan were uniformly distributed in the blended hydrogels.The blended hydrogels were strongly positively charged at acidic pH (pH 3.0),however,the zeta potentials of all the hydrogels were reduced to nearly 0 mV at neutral pH (pH 7.4).There were no significant differences in the adsorption of total FBS proteins and BSA between the blended hydrogel groups.However,the adsorption of FN on the hydrogels significantly increased with the increase of chitosan content.Cell culture experiment indicated that the cytocompatibihty of the blended hydrogels was significantly improved with the increase of chitosan content.The HMECs exhibited higher levels of adhesion,spreading,and proliferation on the hydrogels with higher chitosan content.ConclusionResults in this study indicated that the chitosan component preferentially adsorbed FN compared to the other serum proteins,leading to adhesion and spreading of the cells on the blended hydrogels.In contrast to prevailing views,it was found in the present study that the biocompatibility of chitosan did not relate to its positive charge.