53PREPARATION AND EVALUATION OF SPRAY DRIED MICROPARTICLES USING CHITOSAN AND NOVEL CHITOSAN DERIVATIVE FOR CONTROLLED RELEASE OF AN ANTIPSYCHOTIC DRUGThe objective of the study was to prepare and evaluate Chitosan and carboxymethyl chitosan (chitosan derivative) clozapine loaded microparticles by the spray drying technique for controlled release. Clozapine (CZ), atypical antipsychotic therapeutically effective in both the positive and negative symptoms of schizophrenia was chosen as a model drug. Chitosan was effectively modified to carboxymethyl chitosan (CMC) a novel derivative in order to protect the drug in stomach and to give maximum release of the drug in intestine. Advantage of chitosan derivative (carboxymethyl chitosan) over chitosan is that this is soluble in water and basic pH above 7 and it has less ability to swell in acidic pH so drug will be protected from the detrimental effect of acidic environment present in stomach. Ample number of researches indicating the use of carboxymethyl chitosan (chitosan derivative) for intestinal drug delivery had been reported. Microparticles were successfully prepared with an average size varying from 100±0.25µm to 140±0.25 µm. SEM photographs showed that the prepared CH and CMC microparticles were spherical in nature. Micromeritics properties are found well within limits. FTIR and DSC studies indicate that there are no drug to polymer interaction between the drug and polymer used and drug present in the formulation is in stable state. Swelling studies clearly gives indication about the pH dependency of the prepared CMC. In vitro release studies clearly shows that CMC microparticles release most part of the drug in intestine as compare to pure CH microparticles. Chitosan was successfully modified to carboxymethyl chitosan; hence help in controlling the drug release. The polymer exhibit pH dependent swelling i.e. they swell and release the drug only at a particular pH range, hence site specific drug delivery is possible. mshuaibkhan68@gmail.comResearch312012Clozapine,carboxymethyl chitosan,microparticles,spray drying, pH dependentMohammed S. Khan,Gowda D. Vishakante,Afifa Bathool,Rohitash KumarDept. of Pharmaceutics, JSS College of Pharmacy, JSS University, Sri Shivarathreeshwara Nagara, Mysore-570015, India.,Dept. of Pharmaceutics, JSS College of Pharmacy, JSS University, Sri Shivarathreeshwara Nagara, Mysore-570015, India.,Dept. of Pharmaceutics, JSS College of Pharmacy, JSS University, Sri Shivarathreeshwara Nagara, Mysore-570015, India.,Dept. of Pharmaceutics, JSS College of Pharmacy, JSS University, Sri Shivarathreeshwara Nagara, Mysore-570015, India.