چكيده لاتين :
Anovel synthesis method of biocompatible polymers-coated magnetic nanogels
was developed. Poly(PEGMA) modified superparamagnetic nanogels were synthesized
by in-situ polymerization using poly(ethylene glycol) methacrylate
(PEGMA) as monomer and N,Nי-methylene-bis-(acrylamide) (MBA) as cross-linking
agent in magnetite aqueous suspension under UV irradiation. The surface functional
groups, structure, particle size, Zeta potential and magnetic property were characterized,
respectively. The Fourier transform infrared spectroscopy (FTIR) results indicated
that the poly(PEGMA) modified magnetic nanogels were synthesized successfully
under UV irradiation. The analyses of transmission electron microscopy (TEM) and
photon correlation spectroscopy (peS) indicated that the poly(PEGMA) modified magnetic
nanogels were essentially monodisperse, nearly spherical in shape, the mean
diameter in aqueous solution wai: 68.4 nm, and the size distribution was narrow. The
thermogravimetric analyzer (TGA) result indicated that there was a high Fe304 content
of 53.4% in the magnetic nanogels, which endowed the magnetic nanogels with a
strong magnetic response under external magnetic field. Magnetic measurement
revealed that the saturated magnetization of the poly(PEGMA) magnetic nanogels
reached 58.6 emu/g and the nanogels showed the characteristics of superparamagnetic.
The Zeta potential was -17.3 mV at physiological pH (pH 7.4) which helped maintain
stability in blood. The transverse relaxation time (T2) was also performed for potential
use of magnetic resonance imaging (MRI) contrast agents. The preliminary experiment
verified the feasibility of the magnetic nanogels for potential MRI contrast agents.
