A spoon full of levan…

At SOLVE we have developed a robust, reliable, fast and green method (no harmful chemicals or by products are generated) to accurately characterize levan with respect to molar mass and size distributions using asymmetric flow field-flow fraction coupled with online multiangle light scattering and differential refractive index (AF4-MALS/dRI) detection.

Successful characterization of raw levans with molar masses up to 1010 g/mol and radii up to 400 nm has been achieved. The AF4-MALS/dRI method allows detailed assessment of the raw levan and monitoring of production scale processing to yield a final levan polysaccharide with the desired molar mass and size range. Furthermore, the AF4-MALS/dRI method has been central in laboratory research aimed at identifying optimum processing conditions, assessing long term solution and dry storage stability, and monitoring low levels of macromolecular contaminates in the levan.

Levan is non-toxic, odorless, and tasteless polysaccharide with potential uses in pharmaceutical, medical, cosmetic, food, and textile applications. Fructose is the repeating base unit from which levan is made, and levan can be sourced from either bacteria production or isolated from plants.

The use/performance of levan in specific applications is dependent, in part, on it physicochemical properties such as molar mass, size and branching density. These properties must fall within predetermined tolerances to yield material with similar batch-to-batch performance characteristics. It is critical to be able to fully characterize levan as a raw material and then track changes in physicochemical properties during levan processing to ensure batch-to-batch reproducibility. However, levan is a polydisperse material with respect to molar mass (104–1010 g/mol), size (~20 nm to several hundred nm) and branching (2 – 12 %). Additionally, batch-to-batch and supplier-to-supplier variations of physicochemical properties are observed in raw levans and may be independent of the conditions used to produce the polysaccharide (i.e., type of bacteria and any post collection processing). This places an incredibly high demand on the analytical methods used to characterize the physicochemical properties of levan.

At SOLVE we are experts in the characterization of levan and other polysaccharides. Contact us with any questions you have and we can help you solve them.