Activatable interpolymer complex-superparamagnetic iron oxide nanoparticles as magnetic resonance contrast agents sensitive to oxidative stress

作者：Yoo Eunsoo; Cheng Huaitzung A; Nardacci Lauren E; Beaman David J; Drinnan Charles T; Lee Carmen; Fishbein Kenneth W; Spencer Richard G; Fisher Omar Z; Doiron Amber L^*

来源：Colloids and Surfaces B: Biointerfaces , 2017, 158: 578-588.

DOI：10.1016/j.colsurfb.2017.07.025

• Magnetic resonance imaging
• Activatable contrast
• Nanoparticles
• Oxidative stress
• Superparamagnetic iron oxide nanoparticles

Magnetic resonance contrast agents that can be activated in response to specific triggers hold potential as molecular biosensors that may be of great utility in non-invasive disease diagnosis. We developed an activatable agent based on superparamagnetic iron oxide nanoparticles (SPIOs) that is sensitive to oxidative stress, a factor in the pathophysiology of numerous diseases. SPIOs were coated with poly(ethylene glycol) (PEG) and complexed with poly(gallol), a synthetic tannin. Hydrogen bonding between PEG and poly(gallol) creates a complexed layer around the SPIO that decreases the interaction of solute water with the SPIO, attenuating its magnetic resonance relaxivity. The complexed interpolymer nanoparticle is in an OFF state (decreased T-2 contrast), where the contrast agent has a low T-2 relaxivity of 7 +/- 2 mM(-1) s(-1). In the presence of superoxides, the poly(gallol) is oxidized and the polymers decomplex, allowing solute water to again interact with the SPIO, representing an ON state (increased T-2 contrast) with a T-2 relaxivity of 70 +/- 10 mM(-1) s(-1). These contrast agents show promise as effective sensors for diseases characterized in part by oxidative stress such as atherosclerosis, diabetes, and cancer.

• 出版日期2017-10-1
• 单位NIH