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text can be accessed by clicking on the The journal has now initiated online manuscript submission and peer-review management system in technical collaboration with www.criticalmath.com . Authors can now submit their manuscripts at http://tbao.criticalmath.com . Editorial p
125-137 Antibacterial Activity of Chitosan Chemically Modified
with New Technique M.S. Mohy Eldin1*, E.A. Soliman1,
A.I. Hashem2, T.M. Tamer1 1Polymer Materials Research Department, Received 01 May 2008; Accepted 25 November 2008; published online 23 December 2008 The antibacterial activity of chitosan was chemically modified by introducing further amino groups to the back bone of chitin using parabenzoquinone (pBQ) as activation agent and ethylene di amine (EDA) as amino group source. The aminated chitin was further deacetylated to obtain finally chemically modified chitosan with higher content of amine groups. Factors affecting both activation process, and amination process amine grafting, have been studied through following its effect on the amount of introduced amine groups. The success of grafting process has been confirmed using FT-IR and TGA analysis. The antibacterial activity of the modified chitosan was tested on four different bacterial strains; two gram negative (Escherichia coli, pseudomonas aeruginosa), and two gram positive (Bacillus cereus, Staphylococcus aureus). It was found that the antibacterial activity of the modified chitosan is better than the native one, and increases by increasing the amount of introduced amine group (degree of the grafting), the degree of deacetylation. Lowering the molecular weight was found of negative effect. On the other hand, The Cytotoxicity activity test using Caco 2 cell line shows a safety result. As chitosan, modified chitosan show potential bactericidal activity along all strain examined spatially on the gram negative bacteria (Escherichia coli, pseudomonas aeruginosa). Finally, the modified chitosan shows higher solubility, almost double, at pH range from 5 to 6 comparing to chitosan it self. © Society for Biomaterials and Artificial Organs (India), 20080501-18.p
138-143 Comparative Study of the Behaviour of a Novel Injectable
Bioceramic in Sheep Vertebrae Leif Hermansson1, Urban Höglund2,
Erik Olaisson1, Peter Thomsen3, Håkan Engqvist4 Received 04 May 2008; Accepted 25 November 2008; published online 23 December 2008 Biomaterials used for vertebral compression fractures (VCFs) have previously mainly been based on conventional bone cement, polymethyl methacrylate (PMMA). New alternative materials based on bio-ceramics, e.g. calcium aluminate cements (CAC), are under development. In this in vivo study the biocompatibility and degree of integration/healing was compared between bone and three different cements used for VCFs; Xeraspine™ (a calcium aluminate-based cement), Cortoss™ (a bisphenol-a-glycidyl dimethacrylate based material) and conventional bone cement, Vertebroplastic™ (PMMA) in sheep vertebrae. In addition to an attempt to localize histologically depositions of aluminium aluminium in serum and in selected organs was quantified. Also, histopathological evaluation was conducted to determine the immunological response in the vertebrae caused by the different materials. It was found that Xeraspine was well accepted by the sheep vertebrae and the results were comparable to those of the other cements studied.© Society for Biomaterials and Artificial Organs (India), 20080504-19. p
144-157 How is the Surface Treatments Influence on the Roughness
of Biocompatibility? Mohammad Mohsin Hossain*, Wei Gao Department of Chemical & Materials Engineering, Received 17 May 2008; Accepted 25 November 2008; published online 23 December 2008 It is well known that the extensive uses of biomaterial for biomedical implantation depend on biocompatibility. In order to improve biocompatibility of titanium alloys several factors are needed to be studied. These factors include surface roughness, surface coating materials, surface oxide film and apatite-forming-ability. There are inadequate results existed in literatures on how bioactive material surface to be processed to become a secure surface oxide film on the substrates. There are also imperfect information about the bonding strength between the surface oxide film and bioactive material. So, the firm of surface oxide film by physico-chemical process is the key premise for future development of bioactive material. The rationale of literature surveys to find out the most convenient techniques for measuring surface roughness, modifying surface oxide film and effective applications in biomedical implantation. © Society for Biomaterials and Artificial Organs (India), 20080517-20. p
158-168
Chitosan Modified Membranes for Wound Dressing
Applications: Preparations, Characterization and Bio-Evaluation M.S. Mohy Eldin1*, E.A. Soliman1, A.I. Hashem2,
T.M. Tamer1 1Polymer Materials Research Department Received 19 May 2008; Accepted 25 November 2008; published online 23 December 2008 Modified chitosan membranes for wound dressing application has been prepared, characterized and evaluated. New chemical route has been used to modify antibacterial activity of chitosan through grafting of extra amine groups in addition to the original ones. This process has been verified with FT-IR analysis and solubility test.. The prepared membranes from modified chitosan were characterized from physicochemical point of view. Properties like water uptake, tensile strength, elongation, water vapor permeability and surface roughness have been monitored. Evaluation of the membranes as wound dressing has been done through investigation of its antibacterial activity against different microorganisms, gram negative and gram positive bacteria, cytotoxicity, biodegradability and Haemocompatability. The modified chitosan membranes show high profile as a wound dressing biomaterial. © Society for Biomaterials and Artificial Organs (India), 20080519-21. p
169-178 Development and Characterization of Polymer Ceramic Composites for Orthopedic Applications J. Kamaraj, E. Swaminathan, S. Dharmalingam * Department of Chemistry, Anna University Chennai,
Chennai-600025, India Received 01 July 2008; Accepted 25 November 2008; published online 23 December 2008 In the present work, synthetic composites were prepared using Polyether ether ketone (PEEK) and Poly styrene (ethylene-butylene) polystyrene (PSEBS) as polymer matrices and Hydroxyapatite as the ceramic. In order to have chemical interactions possible with –OH group of Hydroxyapatite, the polymers were sulphonated. By doing so, the drawback of Hydroxyapatite, i.e., its migration from the site of implant in the body can be avoided. Thus a better interface of Hydroxyapatite with the polymer matrix can be expected. In order to study the effect of biocompatibility of HAP in sulphonated PEEK and PSEBS, a series of two sets of composites (each having 5 different proportions) were prepared. Then, the water swelling studies, biocompatibility tests were performed. Biocompatibility tests include clot formation test, % Haemolysis and protein adsorption test. Then the prepared composites were characterized by FT-IR, XRD and TGA. © Society for Biomaterials and Artificial Organs (India), 20080701-21.
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