Development of chitosan nanoparticles as drug delivery systems for 5-fluorouracil and leucovorin blends

Both 5-fluorouracil (5-FU) and leucovorin (LV) are hydrophilic drugs which are used in combination for the treatment of colon cancer. Chitosan (CS) nanoparticles were prepared by ionic gelation technology, and then used for trapping 5-FU and LV. Combination drugs were encapsulated into CS nanoparticles as a result of electrostatic interactions, which was confirmed by Fourier transform spectroscopy (FTIR). XRD results demonstrated that the both drugs were distributed in the CS nanoparticles in the amorphous state. Efficient encapsulation efficiency (EE) and loading capacity (LC) were achieved which were correlated to their initial drug concentration. Simultaneous release of 5-FU and LV from CS nanoparticles were observed in vitro studies; both 5-FU and LV experienced initial burst release which was followed by a constant and continuous release. The release of drugs was influenced by their initial drug concentration, indicating that the release of drugs could be controlled by varying the initial drug concentration. All results suggested that CS nanoparticles are promising system for simultaneously delivering 5-FU and LV in treatment of colon cancer. (C) 2011 Elsevier Ltd. All rights reserved.