Systhesis of magnetic thermosensitive hydrogel and its heat effect under alternating magnetic field / 中国药学杂志

ABSTRACT

OBJECTIVE: To synthesize magnetic thermosensitive hydrogel and study its heat effect under alternating magnetic field in vitro. METHODS: PLGA-PEG-PLGA triblock copolymer was synthesized by ring-opening polymerization of D, L-lactide and glycolide with PEG1500 in the presence of stannous iso caprylate. Magnetic thermosensitive hydrogel of different concentrations were prepared using different currents. The influences of the concentration of magnetic fluid and current of magnetic field on the heat effect were separately observed. RESULTS: The synthetized PLGA-PEG-PLGA triblock copolymer was excellently temperature sensitive. It retained the thermo-sensitivity of original hydrogel when the magnetic fluid was loaded. The 5, 10 and 20 min heating ability of magnetic fluid was positively linearly correlated with its concentration (r=0.9985, 0.9893 and 0.9711, respectively, n=3) and current of magnetic field (r=0.9948, 0.9977 and 0.9994, respectively, n=4). CONCLUSION: The magnetic thermosensitive hydrogel has excellent temperature sensitivity. When alternating magnetic field is applied, the temperature of the system can rise and reach above LCST of hydrogel. The temperature can be controlled by changing the concentration of magnetic fluid and the current of magnetic field. Copyright 2012 by the Chinese Pharmaceutical Association.