Saba Sayyareh - Master's Student, Biomedical Engineering, Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran
Reza Karimi-Soflou - Ph.D., Biomedical Engineering, Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran
Akbar Karkhaneh - Associate Professor, Biomedical Engineering, Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Iran

Diabetic patients often suffer from chronic, non-healing wounds due to underlying disease pathology. These wounds require advanced dressings that can simultaneously fight infection, reduce inflammation, and promote tissue regeneration and blood vessel growth. Hydrogen sulfide (H۲S) is an ideal candidate for such a multifunctional approach. As a natural signaling molecule in the body, H۲S plays various biological roles. Specifically, H۲S has been shown to stimulate angiogenesis and reduce inflammation, making it well-suited to improve diabetic wound healing. Intelligent dressing designs that leverage H۲S release could provide a much-needed solution for managing this chronic complication of diabetes. Sustained release hydrogen sulfide microparticles for topical wound powder application were successfully developed in this study. The microparticles were fabricated using the FDA-approved polyester polylactic acid (PLA). Sodium hydrosulfide (NaHS) was encapsulated within the PLA particles. Upon contact with wound exudate, NaHS undergoes a hydrolytic reaction to generate H۲S and sodium hydroxide. The microparticles were synthesized via a water-in-oil-in-water emulsion technique, yielding spherical particles with a mean diameter of ۸.۵ ± ۲.۹ μm and low polydispersity of ۰.۱۵. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) confirmed the morphology and successful encapsulation of NaHS within PLA, respectively. The microparticles demonstrated high yield (۷۸ ± ۵%) and NaHS encapsulation efficiency (۸۰ ± ۶.۲%). The release profile showed an initial ۴۰ μM H۲S burst followed by sustained low-level release of ۵ μM over ۱۰ days. This was lower than free NaHS, indicating efficient control by the particles. MTT assay revealed the microparticles were non-toxic to human dermal fibroblasts. In fact, the particles significantly promoted fibroblast growth and proliferation. Overall, these NaHS-loaded microparticles show potential for diabetic wound treatment via topical application alone or when incorporated into various wound dressings.

Microparticle, Hydrogen Sulfide Release, Polylactic Acid, Diabetic Wound Treatment