Development of alginate gel dressing

Alginate-based wound dressing materials have been widely used to promote wound healing and to reduce blood loss from wounds. However, recently a few drawbacks of well-established commercial alginate dressings have been reported. Therefore, we tried to develop a new alginate dressing to reduce the drawbacks. First, four new dressings with different calcium content were prepared, and the cytotoxicity of these four materials, and Kaltostat and Sorbsan, was tested in vitro by culture of fibroblasts with their extracts. Second, full-thickness wounds in pigs were used for the evaluation of wound healing in vivo. Finally, a newly developed alginate dressing was used clinically for treatment of split-thickness skin graft donor sites. The extract medium from ALG3, ALG4, Kaltostat, and Sorbsan induced a significant inhibitory effect on proliferation of fibroblasts. As for wound closure rate, the ALG2-covered wounds had the smallest wound area on day 15. Histologically, foreign-body reaction was least in ALG2-treated wounds. In a clinical study, the main drawback of ALG2 was leakage of wound exudate due to dissolution of the dressing material. However, the transparency of moistened ALG2 allowed easy evaluation of the wound, and after healing it was easy to remove ALG2 from the wound without injury to the reepithelialized skin because ALG2 was relatively nonadherent to the wound.