One‐Step, Room‐Temperature Synthesis of Glutathione‐Capped Iron‐Oxide Nanoparticles and their Application in In Vivo T1‐Weighted Magnetic Resonance Imaging. Issue 19 (9th July 2014)

• Record Type: Journal Article
• Authors: Liu, Chien‐Liang; Peng, Yung‐Kang; Chou, Shang‐Wei; Tseng, Wei‐Hsuan; Tseng, Yu‐Jui; Chen, Hsieh‐Chih; Hsiao, Jong‐Kai; Chou, Pi‐Tai
• Is Part Of: Small. Volume 10:Issue 19(2014:Oct.)
• Page Start: 3962
• Page End: 3969
• Publication Date: 2014-07-09
• Subjects: Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201303868
• Languages: English
• ISSNs: 1613-6810

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The room‐temperature, aqueous‐phase synthesis of iron‐oxide nanoparticles (IO NPs) with glutathione (GSH) is reported. The simple, one‐step reduction involves GSH as a capping agent and tetrakis(hydroxymethyl)phosphonium chloride (THPC) as the reducing agent; GSH is an anti‐oxidant that is abundant in the human body while THPC is commonly used in the synthesis of noble‐metal clusters. Due to their low magnetization and good water‐dispersibility, the resulting GSH‐IO NPs, which are 3.72 ± 0.12 nm in diameter, exhibit a low <italic>r</italic><sub>2</sub> relaxivity (8.28 m<sc>m</sc><sup>−1</sup>s<sup>−1</sup>) and <italic>r</italic><sub>2</sub>/<italic>r</italic><sub>1</sub> ratio (2.28)—both of which are critical for <italic>T</italic><sub>1</sub> contrast agents. This, together with the excellent biocompatibility, makes these NPs an ideal candidate to be a <italic>T</italic><sub>1</sub> contrast agent. Its capability in cellular imaging is illustrated by the high signal intensity in the <italic>T</italic><sub>1</sub>‐weighted magnetic resonance imaging (MRI) of treated HeLa cells. Surprisingly, the GSH‐IO NPs escape ingestion by the hepatic reticuloendothelial system, enabling strong vascular enhancement at the internal carotid artery and superior sagittal sinus, where detection of the thrombus is critical for diagnosing a stroke. Moreover, serial <italic>T</italic><sub>1</sub>‐ and <italic>T</italic><sub>2</sub>‐weighted time‐dependent MR images are resolved for a rat's kidneys, unveiling detailed cortical‐medullary anatomy and renal physiological functions. The newly developed GSH‐IO NPs thus open a new dimension in efforts towards high‐performance, long‐circulating MRI contrast agents that have biotargeting potential.</p> </abstract>