Phytospherix® is a plant derived carbohydrate based polymeric nanomaterial.

Glycogen is a highly branched glucose polymer that functions as an energy storage medium in animals, fungi and bacteria. These polysaccharides are present in animal tissue (mainly in the liver) in the form of dense particles with diameters of 20 – 200 nm and are composed of α-1,4-glucans, highly branched via α-1,6-glucosidic linkages.  Research has shown that some plants also produce a form of glycogen called phytoglycogen. Phytoglycogen and glycogen are very similar in terms of chemistry, structural features and molecular size range. An abundant source for phytoglycogen is the kernel of mutant corn (su-1), a primary genotype of commercial sweet corn.

Glycogen and phytoglycogen are normally considered “highly polydisperse” or heterogeneous materials. Commonly reported glycogen or phytoglycogen particle diameters are in the range of 20 – 300 nm and have either continuous or multimodal size distribution. Small, 20 – 30 nm in diameter, particles are termed β-particles and large, 100 – 300 nm in diameter, α-particles. The α-particles are considered to be composed of β-particles as a result of aggregation or clustering. Phytoglycogen is similar to animal glycogen – both for the range of molecular size distribution and the presence of α-particles.

Various methods have been developed to isolate glycogen and phytoglycogen from living organisms. These methods are typically used to quantify the amount of total glycogen accumulated in biological samples and, infrequently, for the purpose of using the glycogen as a product in applications. MBI’s proprietary process of extracting phytoglycogen from sweet corn is the basis for the highly purified monodisperse Phytospherix® material.

Phytoglycogen nanoparticles can be easily modified with standard chemical methods. This allows for functionalizing the surface or for attaching active pharmaceutical ingredients (APIs), peptides, nucleotides, chromophores and markers to the nanoparticle. In this way, the properties of Phytospherix® can be optimized for specific biological applications.