Characterization of Composite Agarose-Collagen Hydrogels for Chondrocyte Culture

To elucidate the mechanisms of cellular mechanotransduction, it is necessary to employ biomaterials that effectively merge biofunctionality with appropriate mechanical characteristics. Agarose and collagen separately are common biopolymers used in cartilage mechanobiology and mechanotransduction studies but lack features that make them ideal for functional engineered cartilage. In this study, agarose (8% w/v and 4% w/v) is blended with collagen type I (4mg/mL) to create composites. We hypothesized that a higher stiffness, composite hydrogel would promote native cartilage-like conditions. To address these questions, acellular and cell-laden studies were completed to assess rheologic and compressive properties, contraction, and structural homogeneity in addition to matrix mechanics, cell proliferation, and glycosaminoglycan production. Over 21 days in culture, cellular 4% agarose – 2mg/mL collagen I hydrogels displayed good structural and bulk mechanical properties, cell proliferation, and continual glycosaminoglycan production, indicating promise towards the development of an effective hydrogel for chondrocyte mechanotransduction and mechanobiology studies.