International Journal of Therapeutic Applications, Volume 9, 2013, 20-26 20 EFFECT OF SOLUBILITY OF DIFFERENT EXCIPIENTS ON DRUG RELEASE OF CHITOSAN MATRIX TABLET OF ACECLOFENAC: A STUDY Ramesh G. Katedeshmukh 1*, Adhikrao V. Yadav 2 1 Govt. College of Pharmacy, Karad, Dist-Satara, MS, India-415 110. 2 Gourishankar Institute of Pharmaceutical Education and Research, Limb, Satara, MS, India-415 206. INTRODUCTION Chitosan, a linear binary heteropolysaccharide, is composed of β-1,4-linked glucosamine (GlcN) with various degrees of N-acetylation of GlcN residues 1-5 . Chitosan occurs naturally in some microorganisms, yeast and fungi 6-8 . It is a non-toxic, biocompatible and biodegradable natural polymer of high molecular weight (~500,000 kDa) 9, 10 . It is the second most common polysaccharide occurring in nature after cellulose. Chitosan is prepared by alkaline N- deacetylation of chitin using concentrated sodium hydroxide (NaOH) solutions at high temperature for a long period of time 1, 11 . Another approach to produce chitosan is by enzymatic N-deacetylation under relatively mild conditions. 12-15 The commercially available chitosan is mostly derived by alkaline N-deacetylation from chitin of crustaceans because it is easily obtainable from the shells of crabs, shrimps, lobsters and krill 16, 17 . The degree of deacetylation (DD) and molecular weight (MW) are two fundamental parameters that can affect the properties and functionality of chitosan 11, 13, 18 . These properties include solubility 12, 19, 20 , viscosity 10 , reactivity such as heavy metal ion chelation 21 and proteinaceous material coagulation 2 , loading (enzyme-loaded) properties and film properties such as tensile strength, elasticity, elongation and moisture absorption 22-27 . With the apparent pKa value of the amino group of about 6.5 22, 23 , chitosan is only soluble in aqueous acidic solutions and insoluble in water and alkaline solutions 24 . Matrix systems generally consist of dissolved or dispersed drug within a swelling or slowly eroding polymer matrix. The drug release from such systems is controlled by water penetration into the matrix followed by either diffusion of the drug into the surrounding medium, erosion of the matrix, or combination of both. A potential disadvantage of the simple monolithic matrix system is the lack of zero- order release kinetics resulting from time-dependent changes in the diffusion path length and surface area. Such delivery systems are widely used to *Corresponding author: Email: krganpati55@gmail.com ABSTRACT Until now numerous oral controlled drug delivery systems have been developed to prolong drug release. The crucial point in this respect is that the drug has to be absorbed well throughout the whole gastrointestinal tract. Chitosan, a linear binary heteropolysaccharide, composed of β-1, 4-linked glucosamine (GlcN) with various degrees of N-acetylation of GlcN residues. It is a non-toxic, biocompatible and biodegradable natural polymer of high molecular weight (~500,000 kDa). Chitosan is prepared by alkaline N-deacetylation of chitin using concentrated sodium hydroxide (NaOH) solutions at high temperature for a long period of time. The degree of deacetylation (DD) and molecular weight (MW) are two fundamental parameters that can affect the properties and functionality of chitosan. Hydrophilic polymers are widely used in controlled release systems due to their favorable functionality. Enhancing the mobility of the polymer chains and diffusing of the drug out from such polymer matrices could be done by inclusion of different types of excipients at different concentrations. The present manuscript describes the attempt made to investigate the influence of the excipient type on matrix hydration, erosion and drug release from matrix systems with a highly soluble excipients and water-insoluble excipients and varying concentration of chitosan A (20% & 30%). Key words: Matrix systems, chitosan A, Aceclofenac, MCC, drug release.