Preparation and Characterization of Low-Methoxyl Pectin/Bletilla Striata Composite Membranes

摘要

The skin is the largest organ in the body composed of the epidermis, dermis, and subcutaneous tissue through the latter it is integrated with deeper tissues. The major function of the skin is to shield out attacks, acting as a barrier. The skin can trigger a series of self-healing procedure when it is damaged. The healing process can be divided into three phases: inflammatory, tissue hyperplasia, and tissue reconstruction. Particularly during tissue hyperplasia, fibroblast proliferation and collagen deposition play important roles in the healing. The healing could be accelerated if wound dressing can be properly applied. An ideal wound dressing is capable of absorbing tissue fluid, keeping the wound moistured, stopping bleeding, attaching to the wound surface properly without sticking to the wound tissues, protecting the wound from infection, and accelerating the wound recovery. In this study, the composite membranes was made by adding mixed solutions of low-methoxyl pectin and Bletilla striata, which is a traditional Chinese medicine, into calcium chloride solution. The low-methoxyl pectin is cross-linked with calcium ions, forming a hydrogel. Membranes of varying ratio of the low-methoxyl pectin and Bletilla striata were prepared seeking for the optimal manufacturing parameters to use to investigate its effects on the water stability, water retention, contact angle and degree of swelling of the composite membranes. The results showed that when the ratio of low-methoxyl pectin solutioin (2 wt%) and Bletilla striata extract is 80/20 was added into 40 ml of 0.3 wt% calcium chloride solution, the composite membrane had the optimal performance in terms of the water stability, water retention, and swelling.