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Abstract Chitosan is considered one of the most important natural polymers that have wide applications in biomaterials and biomedical field such as antimicrobial materials and many other potential applications that can be opened because of it’s unique characteristics . Chitosan was defind as a linear hetero polysaccharide composed of randomly distributed β-1,4- linked-D-glucosamine(GlcN)and N-acetyl-D-glucosamine (GlcNAc) in varying proportion .The proportion of GlcNAc in relation to GlcN units is defined as the degree of N-acetylation (DA ) and differentiates chitin (DA >0.5)from chitosan (DA ≤ 0.5). Several researches have been extensively studied the various factors affecting chitosan properties such as molecular weight and deacetylation degree. Chitosan was produced commercially from crustaceans such as shrimp and crab .Chitosan has a large number of free amino groups in it’s linear chain that make it susceptible to chemical reactions such as reaction with aldehydes or ketones to form the corresponding Schiff base .This study was aimed to prepare films from chitosan derivatives for medical applications. To achieve this target, this study was divided into four sections: 1- Chitosan Schiff base preparation . 2- characterization and antibacterial activity evaluation for the prepared chitosan Schiff bases . 3- Chitosan-β-lactam preparation . 4- characterization and antibacterial activity evaluation for the prepared chitosan-β-lactam . د O O NH2 OH O NH2 OH O NHCOMe OH O O O n HO HO HO + O O NH2 OH O N OH O NHCOMe OH O O O n HO HO HO HC R R CHO AcOH R=H,OMe,Cl,N(CH3)2 1- Chitosan Schiff base Preparation : Chitosan Schiff bases were produced from the condensation reaction between chitosan (50 KDa) and four aromatic aldehydes (benzaldehyde,4-chlorobenzaldehyde,4-N,N-dimethylaminobenzaldehyde and 4-methoxybenzaldehyde ) .In this section the two factors effect of molar ratio and effect of function groups had been studied . |