Characterization of Cellulose Nanocrystals Extracted from Sugarcane Bagasse for Potential Biomedical Materials

Cellulose nanocrystals (CNCs) were extracted by sulfuric acid from cellulose purified via an environmentally friendly method. In this study, cellulose obtained from sugarcane bagasse (SCB) using steam-exploded and enzyme-treated pretreatment was confirmed using chemical composition analysis to have a 92.59 +/- 0.12 whiteness index and 87% alpha-cellulose content. The morphology of extracted CNCs, characterized using atomic force microscopy images, transmission electron microscopy images and energy-dispersive x-rays, showed the diameter and length were in the ranges 9.8 +/- 6.3 and 280.1 +/- 73.3 nm, respectively, with an expected ratio (L/d) of 20-25 and a low concentration of sulfate (0.2%) on surface particles. Moreover, fourier transformed infrared spectroscopy and X-ray diffraction results demonstrated free noncellulosic contents and an improved crystallinity for CNCs, respectively. A decrease in the thermal stability of CNCs was examined by thermogravimetric analysis, and no evidence of cytotoxicity in the CNCs was obtained. The isolated CNCs from SCB may be considered as a potential biomedical material.