(602b) Two Different Synthetic Approaches to Obtain Levan Nanoparticles

Levan is a fructose biopolymer with some useful properties related to different biomedical applications. For instance, that polymer shows cell recognition as well as the cells overexpress GLUT5, which is a fructose transporter overexpressed in different carcinoma cell lines, such as colorectal or liver lines (1). In addition, levan forms nanoparticle when is put in contact with water, due to its amphiphilic properties. Therefore, those properties make possible to create nanoparticles of this polymer with specific cancer recognition (2).

Levan is obtained with the transfructosylation reaction in which an enzyme (levansucrose) breaks the sucrose bond to produce glucose and fructose, to later polimeryze the fructose monomers. This reaction can be carried out by microorganism, or by using directly the isolated enzyme in a cell-free system.

This work aims to compare levan nanoparticles that are obtained from the above explained methodologies. According to the results, cell-free systems provide levan nanoparticles with a smaller particle size distribution in comparison with the particles from microorganisms. Furthermore, nanoparticles produced by cell-free systems have more glucose residues, although its molecular weight is lower compared with the values from the polymer obtained from microorganisms. Both systems were characterized by TEM, TGA, FTIR and its cell internalization process was studied in different cell lines. Both nanoparticle systems were non- toxic. They are taken up by the cells by an endocytic mechanism.

Finally, levan from the cell-free system is obtained faster and with a higher yield than the polyfructose from microorganisms due to the reduction of steps in its downstreaming.