International Journal of PharmTech Research CODEN (USA): IJPRIF ISSN : 0974-4304 Vol.1, No.3, pp 905-913, July-Sept 2009 PREPARATION AND IN VITRO EVALUATION OF CHLORPHENIRAMINE MALEATE LOADED MICROSPHERES Bhaskar Mazumder 1* , Sanjib Bhattacharya 2 , Bibhash Mohanta 1 , Sanjay Dey 1 Anindya Maity 3 1 Department of Pharmaceutical Sciences, Dibrugarh University, Dibrugarh 786004, Assam, India 2 Bengal School of Technology, Delhi Road, Sugandha, Hooghly 712102, West Bengal, India 3 Department of Pharmaceutical Technology, Jadavpur Universirty, Kolkata 700032, West Bengal, India *E-mail: bhmaz@yahoo.co.in ABSTRACT: The aim of this study is to prepare and characterize the microspheres of chlorpheniramine maleate (CPM) with the combination of cellulose derivatives: ethyl cellulose and cellulose acetate. Microspheres were prepared with the combination of ethyl cellulose and cellulose acetate using oil-in-oil emulsion solvent evaporation method. Microspheres were characterized by particle size analysis, percentage yield, and entrapment efficiency, scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, in vitro release studies and release kinetics. The mean particle size, percentage yield were decreased significantly (p < 0.05) with decrease in drug-polymer ratio, surfactant concentration, stirring speed and volume of continuous phase. SEM and FT-IR studies revealed that the microspheres were spherical; non-aggregated, and porous in nature and drug polymer is compatible. It was found that in vitro release were decreased significantly (p < 0.05) with decrease in drug-polymer ratio and stirring speed but increased significantly (p < 0.05) with increase in surfactant concentration and volume of continuous phase. The analysis of dissolution kinetic data shows that it follows Higuchi model then zero order followed by first order. The result suggests that the combination of cellulose acetate and ethyl cellulose microsphere may be useful for the delivery of chlorpheniramine maleate. Key-words: Chlorpheniramine maleate (CPM), ethyl cellulose, cellulose acetate, emulsion solvent evaporation technique. INTRODUCTION Chlorpheniramine maleate (CPM) is an inverse H 1 antagonist, commonly used in the treatment of asthma and other respiratory tract allergies. They are also common ingredients of the compounds preparation for symptomatic treatment of cough and cold 1 . It is absorbed relatively slowly from the gastrointestinal tract. The plasma concentration of 5.9 and 11 µg/ml are achieved in 2.5 to 6 hours after oral administration. The terminal half-life of CPM after single dosage in human subjects is in between 21 to 27 hours. Oral bioavailability of CPM is low; values are ranging from 25 to 50% 2,3 . Therefore, frequent administration of drug (4 mg for every four to six hours) is necessary to maintain the therapeutic drug level. CPM also has a bitter taste. Hence the development of controlled release therapeutic system for CPM that provides sustain release after single dosage, thereby minimizing the frequent administration, it also reduces the total dose require to elicit pharmacological activity and as well reduces side effect. Gastrointestinal irritation is the major problem due to sudden rise in the concentration of drug in GIT after administration of unit dosage. Micro particulate drug delivery due to the approach that can solve the problem associated with the unit dosage form, as they uniformly distributed through the GIT thereby reduce the total concentration of drug 4 . This type of drug delivery for CPM would be beneficial for an effective and safe therapy of asthma and also mask the bitter taste, thereby increase the oral bioavailability. Ethyl cellulose and cellulose acetate is non- biodegradable and biocompatible polymers, which are