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Novel Chitin and Chitosan Materials,in Wound Dressing. R Jayakumar1 M Prabaharan2 P T Sudheesh Kumar1,S V Nair1 T Furuike3 and H Tamura3. Centre for Nanosciences and Molecular Medicine, Amrita Institute of Medical Sciences and Research Centre. Amrita Vishwa Vidhyapeetham University, 2Department of Chemistry Faculty of Engineering and Technology SRM University. 3Faculty of Chemistry Materials and Bioengineering Kansai University. 1 Introduction, Chitin is the second most abundant natural polysaccharide after cellulose on earth It is a.
high molecular weight linear homopolymer of 1 4 linked N acetylglucosamine N. acetyl 2 amino 2 deoxy D glucopyranose units Chitosan a copolymer of glucosamine and. N acetyl glucosamine units linked by 1 4 glucosidic bonds is a cationic polysaccharide. obtained by alkaline deacetylation of chitin The role of chitin and chitosan as biomaterials. are amazing as evidenced by the published scientific papers and patents Chitin and. chitosan are attracting increasingly more attention recently due to its biological and. physicochemical characteristics Chitin and chitosan with beneficial biological and. antimicrobial properties and high valuable potential for wound healing are attractive for. wound care Healing restores integrity of the injured tissue and prevents organisms from. deregulation of homeostasis The treatment of the wounds has evolved from the ancient. times Initially application of dressing material was aimed at inhibition of bleeding. protection of the wound from environmental irritants as well as water and electrolyte. disturbances Skin plays an important role in homeostasis and the prevention of invasion by. microorganisms Skin generally needs to be covered with a dressing immediately after it. was damaged At present there are three categories of wound dressing biologic synthetic. and biologic synthetic Alloskin and pigskin are biologic dressings commonly used. clinically but they have some disadvantages such as limited supplies high antigenicity. poor adhesiveness and risk of cross contamination Synthetic dressings have long shelf life. induce minimal inflammatory reaction and carry almost no risk of pathogen transmission. In recent years researchers have focused on biologic synthetic dressings Bruin et al 1990. Suzuki et al 1990 which are bilayered and consist of high polymer and biologic materials. These three categories of wound dressing are all used frequently in the clinical setting but. none is without disadvantages An ideal dressing should maintain a moist environment at. the wound interface allow gaseous exchange act as a barrier to microorganisms and. remove excess exudates It should also be non toxic non allergenic nonadherent and easily. www intechopen com, 4 Biomedical Engineering Trends in Materials Science. removed without trauma and it should be made from a readily available biomaterial that. requires minimal processing possesses antimicrobial properties and promotes wound. healing In recent years a large number of research groups are dedicated to produce a new. improved wound dressing by synthesizing and modifying biocompatible materials Shibata. et al 1997 Draye et al 1998 Ulubayram et al 2001, Recent reports are also aiming on the acceleration of the wound repair by systematically. designed dressing materials In particular efforts ware focused on the use of biologically. derived materials such as chitin and its derivatives which are capable of accelerating the. healing processes at molecular cellular and systemic levels Chitin and its derivative. chitosan are biocompatible biodegradable nontoxic anti microbial and hydrating agents. Due to these properties they show good biocompatibility and positive effects on wound. healing Previous studies have shown that chitin based dressings can accelerate the repair of. different tissues and facilitates contraction of wounds and regulates secretion of the. inflammatory mediators such as interleukin 8 prostaglandin E interleukin 1 and others. Chitosan provides a non protein matrix for 3D tissue growth and activates macrophages for. tumoricidal activity It stimulates cell proliferation and histoarchitectural tissue. organization Chitosan is a hemostat which helps in natural blood clotting and blocks nerve. endings and hence reducing pain Chitosan will gradually depolymerize to release N acetyl. D glucosamine which initiates fibroblast proliferation and helps in ordered collagen. deposition and stimulates increased level of natural hyaluronic acid synthesis at the wound. site It helps in faster wound healing and scar prevention Paul Sharma 2004 The. advantage of chitin and chitosan is easily can processed into hydrogels Nagahama et al. 2008a Nagahama et al 2008b Tamura et al 2010 membranes Yosof Wee Lim Khor. 2003 Marreco et al 2004 Jayakumar et al 2007 Jayakumar et al 2008 Jayakumar et al. 2009 Madhumathi et al 2009 nanofibers Shalumon et al 2009 Shalumon et al 2010. Jayakumar et al 2010 beads Yosof Lim Khor 2001 Jayakumar et al 2006. micro nanoparticles Prabaharan Mano 2005 Prabaharan 2008 Anitha et al 2009. Anitha et al 2010 Dev et al 2010 scaffolds Peter et al 2009 Peter et al 2010 Prabaharan. Jayakumar 2009 Maeda et al 2008 and sponges Muramatsu Masuda Yoshihara. Fujisawa 2003 Portero 2007 for various types of biomedical applications such as drug and. gene delivery Prabaharan Mano 2005 Jayakumar et al 2010a wound healing. Jayakumar et al 2005 Jayakumar et al 2007 Jayakumar et al 2010b Jayakumar et al. 2010c Tamura et al 2010 and tissue engineering Jayakumar et al 2005 Jayakumar et al. 2010d Tamura et al 2010 Various forms of wound dressings materials based on chitin and. chitosan derivatives are commercially available The ordered regeneration of wounded. tissues requires the use of chitin and chitosan in the form of non wovens nanofibrils. composites films scaffolds and sponges So far a number of research works have been. published on chitin and chitosan as wound dressing materials However only a few review. articles have been reported about chitin and chitosan based wound dressings with limited. information Ueno Mori Fujinaga 2001 Ravi Kumar 2000 Kim et al 2008 Muzzarelli. 2009 Tamura et al 2010 In this paper we reviewed a recent development and applications. on wound dressing materials based on chitin chitosan and their derivatives. 2 Applications of chitin and chitosan materials in wound dressing. Chitin and chitosan have an accelerating effect on the wound healing process A number of. studies have demonstrated that chitin and chitosan accelerated wound healing Chitin and. www intechopen com, Novel Chitin and Chitosan Materials in Wound Dressing 5. chitosan have been used as nanofibers gels scaffolds membranes filaments powders. granules sponges or as a composite The main biochemical activities of chitin and chitosan. based materials in wound healing are polymorphonuclear cell activation fibroblast. activation cytokine production gaint cell migration and simulation of type IV collagen. synthesis Mezzana 2008 Nanofiber matrices have shown tremendous promise as tissue. engineering scaffolds for skin substitutes The advantages of a scaffold composed of. ultrafine continuous fibers are oxygen permeable high porosity variable pore size. distribution high surface to volume ratio and most importantly morphological similarity to. natural extracellular matrix ECM in skin which promote cell adhesion migration and. proliferation Recent advances in process chemistry have made it possible to make chitin. and chitosan nanofibril materials with more flexibility and useful for the development of. new bio related products Mattioli Belmonte et al 2007 Dibutyrylchitin DBC is a water. soluble chitin derivative with confirmed biological properties DBC is obtained in the. reaction of shrimp chitin with butyric anhydride under heterogeneous condition in which. perchloric acid was used as a catalyst Recently DBC fibrous materials were used for wound. healing applications Chilarski et al 2007 In this study DBC non woven fabrics after. sterilisation were applied to a group of nine patients with different indications Satisfactory. results of wound healing were achieved in most cases especially in cases of burn wounds. and postoperative posttraumatic wounds and various other conditions causing. skin epidermis loss Chilarski et al 2007 The effects of DBC on the repair processes and. its mechanisms of action were studied by Blasinka Drobnik 2007 The results showed. that DBC implanted subcutaneous to the rats increased weight of the granulation tissue. Increased cell number isolated from the wound and cultured on the DBC films was also. revealed DBC elevates the glycosaminoglycans GAG level in the granulation tissue This. study documents the beneficial influence of DBC on the repair which could be explained by. the modification of the extracellular matrix and cell number Blasinka Drobnik 2007 The. effectiveness of three chitin nanofibril chitosan glycolate based preparations a spray Chit. A a gel Chit B and a gauze Chit C in healing cutaneous lesions was assessed. macroscopically and by light microscopy immunohistochemistry Mattioli Belmonte et al. 2007 These evaluations were compared to the results obtained using a laser co treatment. The wound repair provided by these preparations are clearly evident even without the. synergistic effect of the laser co treatment These results confirmed the effectiveness of chitin. nanofibril chitosan glycolate based products in restoring subcutaneous architecture. A biocompatible carboxyethyl chitosan poly vinyl alcohol CECS PVA nanofibers were. prepared by electrospinning of aqueous CECS PVA solution Zhou et al 2008 as wound. dressing material The potential use of the CECS PVA electrospun fiber mats as scaffolding. materials for skin regeneration was evaluated in vitro using mouse fibroblasts L929 as. reference cell line Indirect cytotoxicity assessment of the fiber mats indicated that the. CECS PVA electrospun mat was non toxic to the L929 cell Cell culture results showed that. fibrous mats were good in promoting the L929 cell attachment and proliferation Zhou et al. 2008 This novel electrospun matrix would be used as potential wound dressing for skin. regeneration It is known that chitosan derivatives with quaternary ammonium groups. possess high efficacy against bacteria and fungi It is now widely accepted that the target site. of these cationic polymers is the cytoplasmic membrane of bacterial cells Tashiro 2001. The photo cross linked electrospun mats containing quaternary chitosan QCS were. efficient in inhibiting growth of Gram positive bacteria and Gram negative bacteria. Ignatove et al 2007 These results suggested that the cross linked QCS PVP electrospun. www intechopen com, 6 Biomedical Engineering Trends in Materials Science. mats are promising materials for wound dressing applications Similarly the photo cross. linked electrospun nano fibrous QCS PVA mats had a good bactericidal activity against the. Gram negative bacteria E coli and Gram positive bacteria S aureus Ignatove et al 2006. These characteristic features of the electrospun mats reveal their high potential for wound. dressing applications A remarkable wet spun alginate composite containing 0 15 2 0. chitin nanofibrils was also characterized in view of its use as a wound dressing material. Turner et al 1986 Watthanaphanit Supaphol Tamura Tokura Rujiravanit 2008 The. result showed that the overall susceptibility to lysozyme was improved by the tiny amounts. of chitin nanofibrils Moreover the release of chitin oligomers as a consequence of the. enzymatic hydrolysis is a significant contribution to the efficacy of the calcium alginate. dressings The best biomaterials for wound dressing should be biocompatible and promote. the growth of dermis and epidermis layers Chen et al 2008 reported composite. nanofibrous membrane of chitosan collagen which are known for their beneficial effects on. wound healing The membrane was found to promote wound healing and induce cell. migration and proliferation From animal studies the nanofibrous membrane was found to. be better than gauze and commercial collagen sponge in wound healing. A wound dressing system with high liquid absorbing biocompatibility and antibacterial. properties was designed based on chitosan collagen Wang Su Chen 2008 Various. solution weight ratios of collagen to chitosan were used to immobilize on the polypropylene. nonwoven fabric which were pre grafted with acrylic acid AA or N isopropyl acrylamide. NIPAAm to construct a durable sandwich wound dressing membrane with high water. absorbing easy removal and antibacterial activity Swelling properties and antibacterial. activity of the membranes were measured and wound healing enhancement by skin full. thickness excision on animal model was examined The results indicated that NIPAAm. grafted and collagen chitosan immobilized polypropylene nonwoven fabric PP NIPAAm. collagen chitosan showed a better healing effect than AA grafted and. collagen chitosanimmobilized polypropylene nonwoven fabric PP AA collagen chitosan. The wound treated with PP NIPAAm collagen chitosan demonstrated the excellent. remodeling effect in histological examination with respect to the construction of vein. epidermis and dermis at 21 days after skin injury The values of water uptake and water. diffusion coefficient for PP NIPAAm collagen chitosan were higher than that for PP AA. 1 Novel Chitin and Chitosan Materials in Wound Dressing R Jayakumar 1 M Prabaharan 2 P T Sudheesh Kumar 1 S V Nair 1 T Furuike 3 and H Tamura 3 1Amrita Centre for Nanosciences and Molecular Medicine Amrita Institute of Medical Sciences and Research Centre Amrita Vishwa Vidhyapeetham University

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