ISO 10993-4 Compliant Hemocompatibility Evaluation of Gellan Gum Hybrid Hydrogels for Biomedical Applications.

This study examines the hemocompatibility of gellan-gum-based hybrid hydrogels, with varying gellan-gum concentrations and constant sodium alginate and silk fibroin concentrations, respectively, in accordance with ISO 10993-4 standards. While previous studies have focused on cytocompatibility, the hemocompatibility of these hydrogels remains underexplored. Hydrogels were formulated with 0.3%, 0.5%, 0.75%, and 1% gellan gum combined with 3% silk fibroin and 4.2% sodium alginate separately, using physical and ionic cross-linking. Swelling behavior was analyzed in phosphate (pH 7.4) and acetic (pH 1.2) buffers and surface morphology was examined by scanning electron microscopy (SEM). Hemocompatibility tests included complete blood count (CBC), coagulation assays, hemolysis index, erythrocyte morphology, and platelet adhesion analysis. Results showed that gellan gum-sodium alginate hydrogels exhibited faster swelling than gellan gum-silk fibroin formulations. SEM indicated smoother surfaces with sodium alginate, while silk fibroin increased roughness, further amplified by higher gellan-gum concentrations. Hemocompatibility assays confirmed normal profiles in formulations with 0.3%, 0.5%, and 0.75% gellan gum, while 1% gellan gum caused significant hemolytic and thrombogenic activity. These findings highlight the excellent hemocompatibility of gellan-gum-based hydrogels, especially the sodium alginate variants, supporting their potential in bioengineering, tissue engineering, and blood-contacting biomedical applications.