Life Science Journal 2015;12(1) http://www.lifesciencesite.com 29 Synthesis of tosylated and trimethylsilylated methyl cellulose as pH-sensitive carrier matrix Maha M. Ibrahim 1 , Tamer Y A Fahmy 1* , Ehab I. Salaheldin1 1 , Fardous Mobarak 1 , Mohamed A. Youssef 2 , Mohamed R. Mabrook 2 1 Cellulose and Paper Department, National Research Center, El-Tahrir St., Dokki, Cairo, Egypt. 2 Helwan University, Faculty of Science, Chemistry Department, Helwan, Cairo, Egypt. drtamer_y_a@yahoo.com Abstract: Lignocellulosic biomass is one of the most abundant renewable resources that can be processed by chemical reactions for the production of value-added products. In the current study, cellulose and methyl cellulose were synthesized from bleached bagasse pulp and were further modified to cellulose derivatives. Cellulose was first extracted from bagasse by acid–alkali pulping process and was derivatized to prepare methyl cellulose. The products were further chemically modified to tosylated methyl cellulose and trimethylsilylated methyl cellulose. The resulting products were investigated by FT-IR and SEM. Cellulose and all derivatives prepared were evaluated as potential pH-sensitive carrier matrices. The effectiveness as carrier was investigated as function of pH and time in various pH solutions, namely 2.0, 3.5 and 5.0. It was indicated that the type of the modified cellulose plays a role in the obtained results. The present work can be considered as a basic line for drug loading and releasing field. [Maha M. Ibrahim, Tamer Y A Fahmy, Ehab I. Salaheldin, Fardous Mobarak, Mohamed A. Youssef, Mohamed R. Mabrook. Synthesis of tosylated and trimethylsilylated methyl cellulose as pH-sensitive carrier matrix. Life Sci J 2015;12(1):29-37]. (ISSN:1097-8135). http://www.lifesciencesite.com . 5 Keywords: Lignocellulosic biomass; Cellulose; Methyl cellulose; Tosylated methyl cellulose; Trimethylsilylated methyl cellulose 1. Introduction Potential biomass such as agricultural residues consists mainly of three different types of biopolymers i.e. cellulose (35–50%), hemicellulose (25–30%)and lignin (25–30%), which are associated with each other (Ragauskas et al., 2006). Degradation of the polysaccharide constituents i.e. cellulose and hemicelluloses results in the generation of hexose and pentose sugars which could be used as versatile starting materials for further conversion to a range of value- added products. Moreover, cellulose is a naturally occurring organic polymer which forms a major component of all woods, grasses, fibers, and seed hairs. Other sources of cellulose are found in the agricultural residues such as straws, sugar cane, banana plants and the cell wall of some algae and bacteria (Hanley et al., 1997; Yu et al., 2005; Liu and Yu, 2005). One of the agricultural harvesting residues abundantly available in Egypt is bagasse, which is a byproduct results from the sugar manufacture. This lignocellulosic biomass feedstock is a complex mixture of three structural biopolymers, i.e. lignin, cellulose and hemicelluloses (Brodeur et al., 2011). Cellulose is a promising biopolymer for the formation of many advanced materials for various applications due to the structural uniformity, being a β 1-4 linked polyglucan. Chemical modifications for the cellulose lead to a drastic change of its properties. Thus the conversion of the OH moieties like esterification including carbanilation, etherification, and nucleophilic displacement reaction (Klemm et al., 1998; Heinze et al., 2006) is of increasing interest. Other modifications are ionic and radical grafting, acetalization, deoxyhalogenation, and oxidation (Akira, 2001). Thus, chemical modification of celluloseis performed to produce cellulose derivatives (cellulosics), which can be tailored for specific industrial applications (Akira, 2001), where cellulosics are in general reproducible, recyclable and biocompatible (Conner, 1995). Most of the cellulose derivatives are safe and non toxic compounds. They are biodegradable and biocompatible with application in industry and pharmacy. Our study aims to synthesize and characterize modified methyl cellulose with trimethylsilylated groups and study of their application as matrix carrier for pH-sensitive study. 2. Material and Methods 2.1. Raw materials: Bagasse, which kindly was provided by Quena for pulp and paper industry, Quena, Egypt, was used in this study as the lignocellulosic raw material. Characterizations for the raw materials, i.e. moisture content, ash, lignin, holocellulose, alpha cellulose and extracted hemicellulose were carried out before and after pulping and bleaching according to TAPPI standard methods, namely T264 cm-07, T211 om-85, T222 om-88, T257 om-85, T203 cm-99 and T204 cm- 07. 2.2. Cellulose isolation Cellulose was isolated from the agricultural raw material by a pretreatment method in which the raw