Utilization of Okra Stem Waste Extracts for the Development of Dual Network and Self-Healing Polysaccharide/Gelatin Hydrogels With Natural Crosslinker Succinic Acid

In this study, okra gum polysaccharides derived from okra stem waste extract were utilized as a raw material for synthesizing hydrogel matrices. The polysaccharide-rich okra gum was combined with gelatin to enhance the gelation properties of the resulting hydrogels. To assess and compare the self-healing capabilities of the fabricated hydrogels, a natural and nontoxic crosslinking agent, succinic acid, was introduced into the hydrogel formulations at different ratios (5%, 7.5%, and 10% w/v), imparting a dual network structure to the hydrogel matrices. Characterization of the synthesized hydrogels was conducted using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) analyses, providing a comprehensive understanding of their structural and thermal properties. Furthermore, a series of three self-healing assays, including gel block fusion tests, electrical conductivity assessments, and mechanical evaluations, were employed to evaluate the influence of succinic acid on the self-healing efficacy of the okra–gelatin hydrogel composites. These investigations revealed promising outcomes, with the succinic acid–enhanced hydrogel formulation exhibiting a remarkable self-healing ratio of 95% and an electrical conductivity recovery rate of 96.2%. Additionally, incorporating succinic acid in different proportions into the OK-GUM-GELSA hydrogel resulted in decreased swelling values. These findings underscore the significant potential of succinic acid as a crosslinking agent in enhancing the self-healing properties of polysaccharide-based hydrogel matrices, thereby paving the way for their promising applications in various fields, such as sustainable hydrogel sensors. These materials can provide environmentally friendly options for monitoring physiological and environmental changes, while their enhanced self-healing properties contribute to more durable and reliable sensors for various electronic applications.