Development and in vitro evaluation of borax cross-linked tamarind seed polysaccharide hydrogel films as an antioxidant and self-healing material for wound healing

Abstract

Conventional hydrogel wound dressings often suffer from mechanical weakness and an inability to self-repair, reducing lifespan and therapeutic benefits. Moreover, it cannot provide an ideal environment for wound healing due to excessive oxidative stress. To address this, we prepared a self-healing hydrogel film composed of tamarind seed polysaccharide (TSP), which possesses antioxidant properties. Fourier transform infrared spectroscopy (FTIR) confirmed the cross-linking between borax and TSP, while scanning electron microscopy (SEM) revealed a highly rigid cross-linked network structure. The thickness, transparency, water vapor transmission rate, tensile stress, and DPPH scavenging activity of formulations F1–F7 range from 0.247 to 0.476 mm, 8.07%–11.05% at 600 nm, 535 g m⁻² day⁻¹ to 1175 g m⁻2 day⁻¹, 2.023–10.75 MPa in the wet state and 11.431–38.15 MPa in the dry state, and 26.12%–53.39% in 6 h, respectively. The optimized formulation F6 exhibited desired properties, including thickness (0.472 ± 0.021 mm), water vapor transmission rate (1175.74 ± 10.675 g m⁻² day⁻¹), tensile stress (10.75 ± 0.620 MPa wet, 38.15 ± 0.795 MPa dry), % swelling ratio (506.04 ± 2.093%), and DPPH scavenging activity (43.64%). From visual inspection, it was observed that the cuts between the segments started to join instantly and were completely attached within 20 min. The optimized formulation showed a healing efficiency of 43.949 ± 0.566%, based on tensile stress measurements of self-healed films, recorded at 6 h. The developed hydrogel film exhibited an in vitro hemolytic rate of 0.33 ± 0.16%, which falls within the safe range, demonstrating good hemocompatibility.