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Polymers derived from natural sources are of interest in the scientific and medical communities, especially soy protein which exhibits low immunogenicity and good mechanical properties, and supports cell proliferation. Soy protein is cost-effective compared to other natural polymers and is attractive also due to its non-animal origin and relatively long storage stability. In the current study, hybrid film structures were developed and studied as a novel wound dressing platform with controlled release of three bioactive agents. The dense top layer is designed to provide mechanical support, control the water vapor permeability and to elute the antibiotic drug cloxacillin and the analgesic drug bupivacaine to the wound site. The porous sub-layer is designed to absorb the wound exudates and release the hemostatic agent tranexamic acid for bleeding control. The results show that the formulation parameters, i.e. crosslinker and plasticizer concentrations, affected the mechanical properties of the wound dressings as well as relevant physical properties (water vapor transmission rate and swelling kinetics), but had almost no effect on the drug-release profiles. While the antibiotic drug and the analgesic drug were released within several hours, the hemostatic agent was released within several minutes, according to the well designed hybrid structure. In conclusion, our novel soy protein hybrid wound dressings are biocompatible, can deliver various drugs simultaneously in a controlled fashion for each drug individually, and can be adjusted to suit various types of wounds by altering their properties through formulation effects.

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Infection of the periodontal pocket presents two major challenges for drug delivery: administration into the periodontal pocket and a high fluid clearance rate in the pocket. The current study aimed to develop and study a novel gelatin-based hydrogel system crosslinked using a carbodiimide, for delivery of chlorhexidine (CHX) directly into the periodontal pocket via injection followed by in situ gelation.The study focused on the effects of the CHX concentration on its release profile and on the hydrogel's physical, mechanical, and biological properties. CHX is a common antiseptic agent and is considered as "gold standard" in dental practice.Its release profile demonstrated 39% burst release during the initial 2 h, followed by a release rate, which decreases with time for 6 days. A mathematical model based on the two-stage desorption theory was perfectly fitted to the experimental release profiles (R 2 > 0.99). Fibroblast viability results of at least 70% were achieved after 24 and 48 h, indicating that the system is biocompatible. The nonloaded and CHX-loaded hydrogels were found suitable for injectability and exhibited desired gelation times of 7.5-10.6 s, that is, compatible for filling a periodontal pocket. They exhibited excellent mechanical properties, such as burst strength (sealing ability) of 233-357 mmHg, tensile modulus of 47-69 kPa, compressive modulus of 58-104 kPa, and tensile strain of 42-113%. In conclusion, the studied CHX eluting hydrogels are of high potential to be used in minor pockets as well as deep pockets and are expected to be suitable for successfully treating a wide range of periodontal infections.

Burn pain is known to be excruciating, and while burn care has greatly advanced, treatment for burn‐related pain is lacking. Current pain relief methods include systemic administration of analgesics, which does not provide high drug concentration at the wound site. In the present study, soy protein was used as the base material for bupivacaine‐loaded hybrid wound dressings. The effect of the formulation on the drug release profile was studied using high performance liquid chromatography, and the cytotoxicity was tested on human fibroblasts. A second‐degree burn model in rats was used to quantify the efficacy of the wound dressings in vivo, using the Rat Grimace Scale. All tested films exhibited high biocompatibility, and the drug release profiles showed rapid release during the initial 5 hr and a continuous slower release for another 24 hr. Significant pain relief was achieved in the animal trials, proving a decrease of 51–68% in pain levels during days 1–3 post‐burn. Hence, the results indicate a safe and controlled bupivacaine release for a period of more than 24 hr, effectively treating pain caused by second‐degree burns. The understanding of the formulation‐properties effects, together with our in vivo study, enables to advance this field toward tailorable systems with high therapeutic potential.