The Effect of Raw Materials on the Properties of Oxidized Cellulose Nanofibers from Bacterial Cellulose

In the present study, nanofibers of oxidized cellulose (OC) were prepared from dried bacterial cellulose using a mixture of nitric acid/phosphoric acid and sodium nitrite. Three types of dried bacterial cellulose were used as raw materials. The results revealed that dried sheet bacterial cellulose (DSBC) yielded 86.8% oxidized cellulose with 19.4% carboxyl content, whereas squeeze-dried bacterial cellulose (SDBC) yielded 53.3% OC with 28.6% carboxyl content, and freeze-dried bacterial cellulose (FDBC) yielded 55.6% of OC with 27.6% carboxyl content. The results revealed that OC neutralized with sodium hydroxide from SDBC showed the best swelling property among all types of OC. SDBC indicated the reduction of CFU exceeds 99.99% for gram-negative bacterium Escherichia coli ATCC 25922 and gram-positive bacterium Staphylococcus aureus ATCC 6538.