Spectroscopic AC susceptibility imaging (sASI) of magnetic nano particles

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:375

Article

Ficko, Bradley W.¹  Nadar, Priyanka M.¹  Diamond, Solomon G.¹ 

[1] Thayer Sch Engn Dartmouth, Hanover, NH 03755 USA

关键词: AC susceptibility;    Imaging;    Nanoparticles;    Modeling;    Spectroscopy;   

DOI  :  10.1016/j.jmmm.2014.10.011

来源: Elsevier

【 摘 要 】

This study demonstrates a method for alternating current (AC) susceptibility imaging (ASI) of magnetic nanoparticles (mNPs) using low cost instrumentation. The ASl method uses AC magnetic susceptibility measurements to create tomographic images using an array of drive coils, compensation coils and fluxgate magnetometers. Using a spectroscopic approach in conjunction with ASI, a series of tomographic images can be created for each frequency measurement set and is termed sASI. The advantage of sASI is that mNPs can be simultaneously characterized and imaged in a biological medium. System calibration was performed by fitting the in-phase and out-of-phase susceptibility measurements of an mNP sample with a hydrodynamic diameter of 100 nm to a Brownian relaxation model (R2=0.96). Samples of mNPs with core diameters of 10 and 40 nm and a sample of 100 nm hydrodynamic diameter were prepared in 0.5 nil tubes. Three mNP samples were arranged in a randomized array and then scanned using sASI with six frequencies between 425 and 925 Hz. The sASI scans showed the location and quantity of the mNP samples (R-2=0.97). Biological compatibility of the sASI method was demonstrated by scanning mNPs that were injected into a pork sausage. The mNP response in the biological medium was found to correlate with a calibration sample (R-2=0.97, p < 0001) These results demonstrate the concept of ASI and advantages of sASI. (C) 2014 Elsevier B.V. All rights reserved

【 授权许可】

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