What is it about?

Structural properties of iron-oxide nanoparticles deeply affect their magnetic performance in many applications such as with superparamagnetic relaxometry, when employed as cell-targeted magnetic nanoparticles for in vivo diagnostics. In this work, we present a detailed characterization of model nanoparticles for this application, with an average size of 25 nm and a narrow size dispersion. Considering the intrinsic structural properties of these model nanoparticles, the study of temperature dependence and correlation between dc-magnetization and superconducting quantum interference detector-relaxometry are discussed based on known theoretical predictions and computer simulations of the magnetic dipole moment and characteristic decay constants. Furthermore, computer simulations provide support in clarifying how important the overall collective magnetization is affected by particle size dispersion, which has a direct role on sustaining the magnetic relaxation signal in the temperature range required in preclinical and clinical settings.

Featured Image

Why is it important?

This manuscript is filling an important gap in the field of SQUID‐relaxometry as a non‐invasive method for detection of specific cancers, following the same MRX measurement methodology described in our previous paper by Flynn et al., Phys. Med. Biol. 62, 734 (2017), “Development of advanced signal processing and source imaging methods for superparamagnetic relaxometry”]. Due to the different temperatures in each scenario (in vitro assays, ex vivo tissues, in vivo animal studies), the temperature trends and correlation between SQUID superparamagnetic relaxometry and dc‐magnetization are of critical importance.


In July 2019 the Center for Devices and Radiological Health (CDRH) of the Food and Drug Administration (FDA) designed our MagSense technology and HER2 test as a Breakthrough Device, which is a significant step in our clinical development program. Qualifying as a Breakthrough Device will allow us to expedite our dialog with the agency and validates that our MagSense technology is not just another medical device but, indeed, represents a transformative opportunity for healthcare and could improve the standard of care for staging HER2 breast cancer.

Jose Vargas
Imagion Biosystems Inc.

Read the Original

This page is a summary of: Temperature trends and correlation between SQUID superparamagnetic relaxometry and dc-magnetization on model iron-oxide nanoparticles, Journal of Applied Physics, January 2020, American Institute of Physics, DOI: 10.1063/1.5131012.
You can read the full text:



The following have contributed to this page