Development of collagen and nano-hydroxyapatite-based novel self-healing cartilage

Abstract

In recent years, research on self-healing polymers for diverse biomedical applications has surged due to their resemblance to the native extracellular matrix. Here, we introduce a novel self-healing hydrogel scaffold made from collagen (Col) and nano-hydroxyapatite (nHA) via a one-pot-synthesis approach under the influence of heating in less than 10 min. Process parameters, including the quantities of Col, guar gum, solvent, nHA, borax, and glycerol in the system were optimized for the minimization of the self-healing time. The synthesized hydrogel and polymers underwent characterization via FTIR, SEM, EDS, TGA, and ¹³C-NMR. Additionally, the hydrogel showed hemocompatibility with only 6.76% hemolysis at 10 µg·mL⁻¹, while the scaffold maintained cellular metabolic activity at all concentrations for 24 h, with the optimal viability at 1 and 2.5 µg·mL⁻¹, sustaining 93.5% and 90% viability, respectively. Moreover, the hydrogel scaffold exhibited rapid self-healing within 30 s of damage, alongside a tough and flexible nature, as indicated by its swelling rate, biodegradation under various biological pH solutions, and tensile strength of 0.75 MPa. Hence, the innovative Col and nHA self-healing hydrogel scaffold emerges as an ideal, non-toxic, cost-effective, and easily synthesized material with promising potential in cartilage repair applications.