Wound dressings materials for

MAJOR APPLICATIONS Biomaterial applications such as dermal implant, carrier of drugs, cell culture matrix, wound dressing, material for hybrid organ, drug delivery system, soft contact lens, tissue implants, cardiovascular graft, artificial heart, etc. Synthetic sausage casings in food industry. ... 

Goodrich, L.R., Moll, H.D., Crisman, M.V., Lessard, P., Bigbie, R.B. Comparison of equine amnion and a nonadherent wound dressing material for bandaging pinch-grafted wounds in ponies. Am. J. Vet. Res. 61(3), 326-329 (2000)... 

Table 3 Course of wound contraction with respect to the wound area at day 0 using different dressing materials for induction of the wound healing in sheep [150]...

Table 4 Bacterial growth under different dressing materials for induction of wound...

Table 6 Summarized results of the experiment with sheep and a comparison of the effects of all dressing materials for induction of wound healing [150]...

Another important example of the diflFerential adhesiveness which protein-dominated surfaces can display, is in the development of artificial skin especially for wound dressings and for temporary covers of extensive burns. C. W. Hall and co-workers 17) showed that relative tissue adhesion to mechanically identical velour fabrics constructed of various materials follows the order predicted by the critical surface tensions of construction material. 

Bacterial Cellulose has been shown to be a highly effective wound dressing material. In fact, the results of burns, diabetic ulcer, healing process can be show in Figs. 10.5 and 10.6a,b. The biomedical applications of BC include meniscus replacements (pig meniscus on the left, BC meniscus on the right), artificial blood vessels and wound dressing for skin healing [12, 20, 21] (Fig. 10.7). 

Wound-dressing materials and tissue engineering are important domains under development [194-200]. New adhesives were proposed recently [201,202], Especially Az-chitosan was shown to be nontoxic, cytocompatible and mechanically suitable in peripheral surgeries [202], Chitosan is suitable for transmucosomal administration of drugs [203],... 

The mentioned characteristics of BNC, as well as other properties such as, for example, its capability of maintaining a moist environment at the wound surface while preventing external bacteria entry, the possibility of designing the shape of the membranes obtained, its ease of sterilization, good permeability, and nontoxicity, makes BNC a very promising biomaterial to be used as woimd-dressing material. Details on the physical and mechanical properties of microbial cellulose which promote its use as wound-dressing material are summarized in Table 2.3. 

For that purpose, disaccharides (cellobiose, lactose, etc.) having a reducing end group, are introduced, in the presence of a reductant, on chitosan in the open-chain form (Yalpani and Hall 1984). These derivatives are water soluble. Fibers made of chitin and chitosan are useful as absorbable structures and wound-dressing materials (Nakajima et al. 1984, Muzzarelli 1997, Ravi Kumar 1999). 

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