Development of a nanoparticle system based on a fructose polymer: Stability and drug release studies

New drug delivery systems (DDSs) with levan or its carboxymethylated form, as carriers, and 5-fluorouracil as a drug, are produced in this work. Levan is obtained after cultivating A. nectaris and polymer nanoparticles are created in water by a self-assembled process. The effect of pH and the ionic strength on polymer nanoparticles aggregation is studied. Basic pHs produces a particle size between 300 and 400 nm with a Z-potential around −20 mV because a basic medium promotes repulsion forces. DDSs of 300-400 nm and a Z-potential about −25 mV are prepared by taking advantage of the amphiphilic properties of the levan. The drug is bound to either levan or carboxymethyllevan surfaces by electrostatic interactions, obtaining the best results at basic pHs. 45-70% of the drug is released from the levan in 23 h depending on the pH preparation, whereas only a low percentage of the drug is released from the carboxymethyllevan.