CATIONIC MAGNETIC NANOCOMPOSITE FOR MAGNETIC TARGETED DRUG DELIVERY AND CONTRAST AGENT

摘要

A magnetic nanocomposite is provided to be stable in an aqueous solution, show excellent magnetic characteristic and be used as a target magnetic drug delivery with improved cell target efficiency due to be surface-modified by cation, thereby being used as contrast media by comprising pharmaceutically acceptable media. A magnetic nanocomposite comprises: a magnetic nanoparticle; a pharmaceutically active ingredient, a surfactant; an anionic polymer layer surrounding the magnetic nanoparticle; and a cationic polymer layer surrounding the anionic polymer layer, wherein the magnetic nanoparticle is a metal selected from the group consisting of Pd, Ag, Cu and Au, at least one magnetic material selected from the group consisting of Co, Mn, Fe, Ni, Gd, Mo, MM'2O4, and MxOy (wherein each M and M' is independently Co, Fe, Ni, Mn, Zn, Gd, or Cr and each x and y satisfies that 0x=3 and 0y=5), or at least one magnetic alloy selected from the group consisting of CoCu, CoPt, FePt, CoSm, NiFe and NiFeCo, the pharmaceutically active ingredient is encapsulated into the anionic polymer layer, the anionic polymer is polyalkylcyanoacetate, and the cationic polymer is at least one selected from the group consisting of polyacrylamide, polyethyleneimine, chitosan, polylysine, and polyvinylamine. A method for preparing the magnetic nanocomposite comprises the steps of: (a) synthesizing the magnetic nanoparticle in a solvent; (b) adding the anionic polymer to the surface of the magnetic nanoparticle to couple the anionic polymer to the magnetic nanoparticle; (c) encapsulating the pharmaceutically active ingredient into the anionic polymer; and (d) surface-modifying the anionic polymer layer with the cationic polymer. Contrast media comprise the magnetic nanocomposite and a pharmaceutically acceptable carrier. Further, a diameter of the magnetic nanoparticle is 1nm to 1000nm and a diameter of the magnetic nanocomposite is 5nm to 200nm.