A one-step facile process for extraction of cellulose from rice husk and its use for mechanical reinforcement of dental glass ionomer cement

Abstract

Cellulose is a widely available and renewable biopolymer that can be extracted from different natural sources such as plants, and bacteria. Rice husk is of special interest as a source of cellulose, as it is abundant and has a high cellulose content. The extraction of cellulose from rice husk has traditionally been a multi-step procedure that is time-consuming and involves the use of harsh chemicals. However, in this study, a one-step facile method was developed and optimized for the extraction of cellulose from rice husks. The process involved adjusting the ratio of sodium hypochlorite solution to the mass of solid rice husk and the progressive removal of non-cellulosic constituents was confirmed via scanning electron microscopy (SEM), and Maule lignin test. The extracted cellulose was then incorporated into glass ionomer cement (GIC) for dental applications. The mechanical properties of the GIC have increased in G12 and G18 vs. an observable decrease in G21 (p = 0.02 and p = 0.01, respectively), including increased compressive strength and stiffness. The addition of 3% cellulose extracted using C12 conditions (1 husk : 12 hypochlorite for 6 h) to GIC has increased GIC mechanical strength by 130% as compared to control GIC. The addition of 1% cellulose extracted using C18 conditions (1 husk : 18 hypochlorite for 6 h) to GIC has increased GIC mechanical strength by 58.5% as compared to the control. In conclusion, cellulose can be extracted from rice husks using a one-step facile method, and its incorporation into GIC can enhance its mechanical properties and improve its potential use for dental applications.