Study On Magnetic/temperature Seneitive Drug Delivery System Loaded Carbamazepine

Objective Using chitosan, N-succinyl chitosan, aiginate, Fe3O4 andβ-GP as main intelligent carriers, magnetic intelligent delivery system loaded carbamazepine was studied first time.Methods CBZ magnetic chitosan-alginate hydrogel beads, CBZ magnetic NSC/alginate hydrogel beads and CS/β-GP thermosensitive hydrogel were prepared by gelation method. The optimum preparation technique was investigated respectively by orthogonal test and single factor design. The characterizations of the two kinds of hydrogels beads were performed by SEM, FTIR and VSM. Swelling behavior and release properties of the two kinds of hydrogel beads in various pH media were investigated, and the release mechanism in vitro was researched. Otherwise, the technology of CS/β-GP was also been optimized, characteristics of gelation and release in various pH environments were investigated.Results The surface morphology of magnetic chitosan-alginate hydrogel beads loaded CBZ and magnetic NSC/alginate hydrogel beads loaded CBZ were spherical and regular. Swelling behavior of the two kinds of hydrogel beads in different pH media are different. In pH 1.5, there is no distinct swelling behavior, and it is opposite in pH 6.8. Also, there is a few drugs released in pH 1.5, and the cumulative release in pH 6.8 during 24h was 100%. Also, sequential release studies showed that there are a few drugs released during the first 2 hours in pH 1.5. After being transferred into pH 6.8, with swelling of the hydrogel network, the drugs encapsulated inner of the beads began to dissociate, cumulative amount of CBZ was 91.63%and 93.41%after 24 h. Thus, CBZ seems not be released in stomach until the beads arrive at intestinal tract if they are given by oral administration. And, there is no remanence effect and coercive force, suggesting that the magnetic hydrogel beads can remain satisfactory superparamagnetic property at room temperature. The gelation time of CS/β-GP was influenced by pH and the degree of deacetylation of chitosan. The gelation time shorten with the increasing of pH, and it became long with the decreasing of degree of deacetylation of chitosan.Conclusion The two kinds of beads show satisfactory magnetic-responsive and sustained-release property. They could be used as a kind of magnetic target sustained-release preparation for therapy of epilepsy. CS/β-GP is liquid at room temperature, it became gels once upon heating to 37℃. CBZ could be released slowly from the gels when it is mixed with CS/β-GP. This delivery system possess many advantages such as reduce administration, improve compliance. It could be degraded by in vivo enzyme, is an ideal intelligent carrier.