Abstract
Background: Iron oxide nanoparticles (IONPs) have increasing applications in biomedicine, however fears over long
term stability of polymer coated particles have arisen. Gold coating IONPs results in particles of increased stability
and robustness. The unique properties of both the iron oxide (magnetic) and gold (surface plasmon resonance)
result in a multimodal platform for use as MRI contrast agents and as a nano-heater.
Results: Here we synthesize IONPs of core diameter 30 nm and gold coat using the seeding method with a poly
(ethylenimine) intermediate layer. The final particles were coated in poly(ethylene glycol) to ensure biocompatibility
and increase retention times in vivo. The particle coating was monitored using FTIR, PCS, UV–vis absorption, TEM,
and EDX. The particles appeared to have little cytotoxic effect when incubated with A375M cells. The resultant
hybrid nanoparticles (HNPs) possessed a maximal absorbance at 600 nm. After laser irradiation in agar phantom a
ΔT of 32°C was achieved after only 90 s exposure (50 μgmL-1). The HNPs appeared to decrease T2 values in line
with previously clinically used MRI contrast agent FeridexW.
Conclusions: The data highlights the potential of these HNPs as dual function MRI contrast agents and nanoheaters for therapies such as cellular hyperthermia or thermo-responsive drug delivery
term stability of polymer coated particles have arisen. Gold coating IONPs results in particles of increased stability
and robustness. The unique properties of both the iron oxide (magnetic) and gold (surface plasmon resonance)
result in a multimodal platform for use as MRI contrast agents and as a nano-heater.
Results: Here we synthesize IONPs of core diameter 30 nm and gold coat using the seeding method with a poly
(ethylenimine) intermediate layer. The final particles were coated in poly(ethylene glycol) to ensure biocompatibility
and increase retention times in vivo. The particle coating was monitored using FTIR, PCS, UV–vis absorption, TEM,
and EDX. The particles appeared to have little cytotoxic effect when incubated with A375M cells. The resultant
hybrid nanoparticles (HNPs) possessed a maximal absorbance at 600 nm. After laser irradiation in agar phantom a
ΔT of 32°C was achieved after only 90 s exposure (50 μgmL-1). The HNPs appeared to decrease T2 values in line
with previously clinically used MRI contrast agent FeridexW.
Conclusions: The data highlights the potential of these HNPs as dual function MRI contrast agents and nanoheaters for therapies such as cellular hyperthermia or thermo-responsive drug delivery
Original language | English |
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Article number | 27 |
Number of pages | 12 |
Journal | Journal of Nanobiotechnology |
Volume | 10 |
DOIs | |
Publication status | E-pub ahead of print - 25 Jun 2012 |
Keywords
- magnetic nanoparticles
- gold nano-shells
- magnetic resonance imaging
- , surface plasmon resonance
- multifunctional nanoparticles