Starch-Gelatin-Based Scaffolds for Cartilage Defect Repair: An in vitro Study Supporting Its Potential Clinical Use

Objective The aim was to investigate starch-gelatin hydrogels as scaffolds for chondrogenesis and compare these with other materials currently in use regarding cell retention and growth. Methods Two variants of starch-gelatin-scaffolds and one chitosan-based scaffold were fabricated by casting and freeze-drying. The resulting materials were analyzed with respect to physicochemical and mechanical properties, cut to size, and seeded with human articular chondrocytes. Cell retention and proliferation were evaluated at 1, 14, and 42 days of culturing. Extracellular matrix production was analyzed by histo- and immunohistochemistry. Comparisons were made with that of commercially available hyaluronan- (Hyalofast ® ) and collagen-based (ChondroGide ® ) scaffolds, and synthesized chitosan hydrogels. Results The starch-gelatin materials exhibited highly porous structures stabilized by hydrogen bonding, with swelling behavior similar to native cartilage and favorable mechanical handling properties. Despite differences in initial cell retention, all materials except chitosan supported robust cell growth, reaching similar levels after 14 days. No significant changes were observed between 14 and 42 days with the exception of Hyalofast ® showing decreased cell number. Chitosan-supported cell growth was more linear over the culture period, but resulted in only half the cell number by day 42 compared with the other materials. Without cells, Hyalofast and one variant of the starch/gelatin hydrogel degraded before day 42. starch/gelatin scaffolds showed collagen I, II, and aggrecan deposition. Conclusion Starch-gelatin scaffolds displayed favorable mechanical properties, supported cell growth comparable to commercial scaffolds, and promoted deposition of cartilage-specific extracellular matrix, highlighting their chondrogenic potential