Development of Cytocompatible Hydrogels as Potential Scaffolds for Surgical Applications

Four hydrogel formulations were synthesized: a control (alginate/gelatin) and three modified variants containing polyethylene glycol (PEG as a plasticizer), boric acid (filler), and a combination of both. The swelling capacity, degradation rate, tensile strength, cytotoxicity toward a human dermal fibroblast culture, and resistance to surgical sutures were evaluated. To enhance mechanical strength, a combined physicochemical approach including chemical crosslinking and treatment with a concentrated ammonium sulfate solution was used to induce the Hofmeister effect. To assess the tensile strength and suturability, tubular structures were fabricated from the hydrogels using 3D-printed molds patented by the authors. The PEG hydrogels and combined composition (PEG + boric acid) showed the best cytocompatibility and fibroblast growth support. Treatment with ammonium sulfate increased the strength of the materials by 40-70 times, enabling surgical suturing and the formation of leak-proof anastomoses. It has been shown that the Hofmeister effect is reversible, indicating that biocompatibility is restored following implantation. Thus, a combined approach to fabrication of hydrogels is proposed that overcomes the critical dilemma of biomedical materials regarding "strength vs biocompatibility". In the future, the developed materials and technologies (including molds) will offer a promising pathway for creating personalized implants of complex shapes suitable for fixation using standard surgical techniques.