Effect of Stresses during Algae Growth on the Dimensions of Extracted Cellulose Nanocrystals

Cellulose nanocrystals are a valuable material resource that can be derived from algae with a wide range of applications, such as filtration and reverse osmosis (RO) membranes. If the dimensions of cellulose nanocrystals were controlled, one could tailor them for specific applications. It was hypothesized that, by stressing algae during its growth through high salinity media or air feeds with high carbon dioxide concentrations, there could be an effect on the biosynthesis of cellulose and, consequently, the dimensions of extracted cellulose nanocrystals. To test this, three algae, Nannochloropsis occulata, Desmodesmus abundans, and Scenedesmus obliquus were grown under ambient air, 10%, 20%, and 40% carbon dioxide concentrations as well as under different salinities. Cellulose nanocrystals were extracted from the algae using a bleaching pretreatment with 1.7 wt% sodium chlorite in an acetic acid buffer¹ followed by a 60 wt% sulfuric acid hydrolysis treatment². Characterization was done through TEM and AFM. The work is ongoing.

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