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High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
A simple and highly sensitive method for magnetic nanoparticle quantitation using 1H-NMR spectroscopy.
Jonathan Gunn1, Rajan K Paranji, Miqin Zhang
1Department of Materials Science and Engineering, University of Washington, Seattle, Washington, USA.
Biophysical Journal
|November 4, 2009
Summary
A new proton nuclear magnetic resonance ((1)H-NMR) spectroscopy method accurately quantifies superparamagnetic iron oxide nanoparticles (SPIONs) regardless of surface coating. This technique offers a sensitive, rapid, and cost-effective solution for SPION analysis in various applications.
Area of Science:
- Nanotechnology
- Biomedical Engineering
- Analytical Chemistry
Background:
- Superparamagnetic iron oxide nanoparticles (SPIONs) show promise in medical diagnosis and therapy.
- Accurate quantification of SPIONs is crucial for standardized research but current methods lack sensitivity and are complex.
- Reliable SPION quantification is needed for consistent development and application studies.
Purpose of the Study:
- To develop a robust and standardized method for quantifying SPIONs.
- To demonstrate the versatility of the method across different SPION types and sample matrices.
- To overcome limitations of existing SPION characterization techniques.
Main Methods:
- Utilized proton nuclear magnetic resonance ((1)H-NMR) spectroscopy.
- Measured water relaxivity shifts (R(1) or R(2)) correlated with SPION concentration.
- Validated the method with unmodified and coated SPIONs, and in the presence of cells.
Main Results:
- Achieved linear correlations between SPION concentration and relaxivities over five orders of magnitude (down to 10 ppb iron).
- Successfully quantified SPIONs in RAW 264.7 macrophage cells down to <10 ng Fe/mL.
- Demonstrated method's independence from SPION surface modification.
Conclusions:
- Proton nuclear magnetic resonance ((1)H-NMR) spectroscopy provides a sensitive, rapid, and cost-effective method for SPION quantification.
- The developed method is applicable to nanoparticle development, in vitro assays, and potentially in vivo biodistribution studies.
- This technique offers significant advantages over current quantitative SPION analysis methods.
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