Development of high throughput, high precision synthesis platforms and characterization methodologies for toxicological studies of nanocellulose

Cellulose is the most abundant natural polymer, is readily available, biodegradable, and inexpensive. Recently, interest is growing around nano-scale cellulose due to the sustainability of these materials, the novel properties, and the overall low environmental impact. The rapid expansion of nanocellulose uses in various applications makes the study of the toxicological properties of these materials of great importance to public health regulators. However, most of the current toxicological studies are highly conflicting, inconclusive, and contradictory. The major reason for these discrepancies is the lack of standardized methods to produce industry-relevant reference nanocellulose and relevant characterization that will expand beyond the traditional cellulose characterization for applications. In order to address these issues, industry-relevant synthesis platforms were developed to produce nanocellulose of controlled properties that can be used as reference materials in toxicological studies. Herein, two types of nanocellulose were synthesized, cellulose nanofibrils and cellulose nanocrystals using the friction grinding platform and an acid hydrolysis approach respectively. The nanocellulose structures were characterized extensively regarding their physicochemical properties, including testing for endotoxins and bacteria contamination.