Swelling Behavior and Drug Release of Polymer Coated Nano Iron Oxide Embedded Hydroxyapatite

Abstract

Spherical calcium-alginate gel beads containing HAIO, iron oxide (IO) nanoparticles embedded on hydroxapatite (HA), were prepared along with and poly (N-isopropylacrylamide) (PNIPAAM) or chitosan. These spheres, HAIO, HAIO-PNIPAAM and HAIO-chitosan spheres, were used as carriers of 5-fluorouracil (5-FU), one of the drugs for cancer chemical therapy, and the 5-FU release behavior in PBS solution was investigated at ambient and elevated temperatures using U-V spectrometry. The amount of the released 5-FU from the HAIO spheres was somewhat higher than that from HAIO-PNIPAAM and HAIO-chitosan spheres at ambient temperature. At elevated temperature, HAIO spheres showed an increase in quantity of released 5-FU. The amount of released 5-FU from HAIO-PNIPAAM spheres was almost the same, and that from HAIO-chitosan spheres was reduced compared to those at ambient temperature. These spheres, HAIO, HAIO-PNIPAAM and HAIO-chitosan spheres, show the similar swelling properties at elevated temperature. However, the combinations of Ca-alginate - PNIPAAM or Ca-alginate - chitosan may produce the different structures, which are core-shell network for HAIO-PNIPAAM spheres and or a polyelectrolyte complex for HAIO-chitosan spheres, leading to a different release behavior of 5-FU.