학술논문

Regulating the thermal response of PNIPAM hydrogels by controlling the adsorption of magnetite nanoparticles.
Document Type
Article
Source
Applied Physics A: Materials Science & Processing. Feb2014, Vol. 114 Issue 2, p585-590. 6p. 3 Diagrams, 1 Chart, 2 Graphs.
Subject
*MAGNETITE
*RESPONSIVE gels
*HYDROGELS
*ADSORPTION (Chemistry)
*NANOPARTICLES
*MAGNETOCALORIC effects
Language
ISSN
0947-8396
Abstract
Thermoswitchable magnetic hydrogels are being extensively investigated because of their great potential for medical applications. Indeed, they can behave as smart carriers able to transport drugs to a chosen part of the body and release them via magneto-thermal activation by an external alternating magnetic field. We report on the magnetization of the thermosensitive poly(N-isopropylacrylamide) hydrogel through the adsorption of controlled amounts of magnetite nanoparticles. We show that the temperature at which the hydrogel contraction occurs (i.e. the lower critical solution temperature) can be controlled from 32 C to 52 C by varying the concentration of adsorbed nanoparticles. This is clearly shown by photon correlation spectroscopy. The results are an advance in the use of the magnetized poly(N-isopropylacrylamide) hydrogel as a flexible and adjustable nanomaterial and are of great interest in numerous applications which require drug release on demand. [ABSTRACT FROM AUTHOR]