Influence of magnetoplasmonic gamma-Fe2O3/Au core/shell nanoparticles on low-field nuclear magnetic resonance
Journal
Scientific Reports
Journal Volume
6
Pages
35477
Date Issued
2016
Author(s)
Chen, Kuen-Lin
Yeh, Yao-Wei
Chen, Jian-Ming
Hong, Yu-Jie
Huang, Tsung-Lin
Deng, Zu-Yin
Wu, Chiu-Hsien
Liao, Su-Hsien
Abstract
Magnetoplasmonic nanoparticles, composed of a plasmonic layer and a magnetic core, have been widely shown as promising contrast agents for magnetic resonance imaging (MRI) applications. However, their application in low-field nuclear magnetic resonance (LFNMR) research remains scarce. Here we synthesised γ-Fe2O3/Au core/shell (γ-Fe2O3 @Au) nanoparticles and subsequently used them in a homemade, high-T c, superconducting quantum interference device (SQUID) LFNMR system. Remarkably, we found that both the proton spin-lattice relaxation time (T 1) and proton spin-spin relaxation time (T2) were influenced by the presence of γ-Fe2O3 @Au nanoparticles. Unlike the spin-spin relaxation rate (1/T2), the spin-lattice relaxation rate (1/T 1) was found to be further enhanced upon exposing the γ-Fe2O3 @Au nanoparticles to 532 nm light during NMR measurements. We showed that the photothermal effect of the plasmonic gold layer after absorbing light energy was responsible for the observed change in T 1. This result reveals a promising method to actively control the contrast of T 1 and T2 in low-field (LF) MRI applications.
Type
journal article