Available online at www.derpharmachemica.com Scholars Research Library Der Pharma Chemica, 2012, 4(4):1619-1625 (http://derpharmachemica.com/archive.html) ISSN 0975-413X CODEN (USA): PCHHAX 1619 www.scholarsresearchlibrary.com Chiotsan Nanoparticles Loaded with Thiocolchicoside Rabindra K. Nanda* Subodh S. Patil and Dipak A. Navathar. Department of Quality Assurance Techniques, Padm. Dr. D. Y. Patil Institute of Pharmaceutical Sciences and Research, Pimpri, Pune-411 018, India. _____________________________________________________________________________________________ ABSTRACT The oral administration of thiocolchicoside as skeletal muscle relaxant remains a less effective management of rheumatism and arthritis owing to poor oral bioavailability. Hence the present study was aimed to develop and evaluate nanoparticles containing thiocolchicoside as potential oral drug delivery system. The thiocolchicoside loaded chitosan nanoparticles were prepared by ionic gelation of chitosan with tripolyphosphate anions (TPP). The nanoparticles were characterized by Scanning Electron Microscopy (SEM), Zeta potential analyser, Fourier Transform Infra-red (FTIR) Spectroscopy and X- ray diffraction (XRD). All the prepared formulations resulted in nano range size particles (200 - 700 nm). The entrapment efficiency were found to be 74%- 81% respectively. The thiocolchicoside was found to be dispersed in the nanoparticles in microcrystalline polymorphic form. The invitro release profile of thiocolchicoside from the nanoparticles showed a sustained release of the drug over a period of 5 hrs. Keyword: Thiocolchicoside , Chitosan, Nanoparticles, Ionic gelation method _____________________________________________________________________________________________ INTRODUCTION Chitosan (CS) is a naturally occurring nontoxic, biocompatible, biodegradable, cationic polysaccharide. This hydrophilic polymer can easily cross-link with counter poly anions like TPP to control the release of drugs CS is a mucoadhesive polymer with permeation enhancing properties which facilitate opening of the epithelial tight junction[1-2]. Moreover Chitosan nanoparticles can be easily prepared under mild conditions, besides can be incorporated with low molecular weight drugs. This characteristic is extremely beneficial for drugs, proteins, genes or hydrophobic molecules that are poorly transported across epithelia. Among the various methods developed for preparation of nanoparticles, ionic gelation method is simple to operate and also to optimize the required particle size of the drug that can penetrate the epithelial membrane and hence this method was followed in the study. Moreover, chitosan has been proposed as a material with a good potential for oral drug delivery [3-6]. Thiocolchicoside (TH) is N-[(7S)-3-(beta-D-glucopyranosyloxy)-1,2-dimethoxy-10-(methylsulfanyl)-9-oxo-5,6,7,9- tetrahydrobenzo[a]heptalen-7-yl]acetamide, a sulfur derivative of colchicoside). Thiocolchicoside is an agonist of the GABA receptors in the central nervous system, exhibiting muscle relaxation, analgesic and local anesthetic activities. Therefore, thiocolchicoside is prescribed for the treatment of orthopedic, traumatic and rheumatologic disorders. The oral relative bioavailability of thiocolchicoside compared with intramuscular administration, is approximately 25%, mainly due to hepatic first pass-effect, with a high intra- and inter-subject variability [7-9].