Abstract
Folate−chitosan nanoparticles, co-loaded with 5-fluourouacil (5-FU) and leucovorin (LV) and prepared by ionic gelation technology were physically microencapsulated by enteric polymer using a solvent evaporation method. Average particle size of the microencapsulated particles was in the range of 15 to 35 µm. High drug encapsulation efficiency was obtained for both 5-FU and LV in the microencapsulated particles. Both drugs were in amorphous state in the microencapsulated particles. By enteric coating, excellent pH-dependent release profile was achieved and no drug release was observed in simulated gastric and intestinal fluids. However, when the pH value reached the soluble threshold of Eudragit S-100, a constant and slow drug release was observed. The results indicated that these microencapsulated particles are a promising vehicle for selectively targeting drugs to colon in the chemotherapy of colon cancer.
Declaration of interest
The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper. The authors would like to acknowledge the financial support by Natural Science Foundation of Hainan Province (No. 512106, No. 513151), and the Fundamental Research Funds from the Environment and Plant Protection Institute, CATAS (No. 2012hzs1J016).