Formulation of biocomposite of ultrasonication mediated cellulose and lignin nanofibers for biomedical applications

Abstract

Current study deals with the synthesis of bio-composites using nanofibres of lignin and cellulose embedded in pectin. Nanofibres of lignin and cellulose were generated through ultrasonication in varying doses and polymerized with pectin in order to formulate biocomposite through atomic transfer radical polymerization technique. The average size of the cellulose and lignin nanofibers formed were of 7.38 nm and 262.1 nm, respectively on ultra-sonicating it (50% amplitude, 2 sec on and off pulses at 30 ºC) for 15 min. Biocomposite was characterized through TGA analysis, which shows thermal degradation start after 100 ºC and at 761ºC about 60% of weight loss was observed, which proved its high thermostability. Scanning electron microscopy study concluded that surface of the biocomposite was smooth and homogenous. The structural analysis using FTIR illustrated ester bond formation between the hydroxyl group of lignin and cellulose with the carboxyl groups of pectin molecules while polymerization, which imparted it thermal stability and strength. On further analysis, biocomposite has shown distinct antioxidant property, negligible cell cytotoxicity and started auto- degenerate just after 15 min in aqueous medium, therefore this can be explored in biomedical and pharmaceutical industries for controlled drug delivery and as drug carrier.