Data from: Characterization data of commercial tracers for magnetic particle imaging
Data files
Mar 13, 2025 version files 6.80 MB
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MPI_tracer_data_25-02-28.zip
6.80 MB
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README.md
3.76 KB
Abstract
This dataset contains characterization data for various commercially available tracers for magnetic particle imaging (MPI). Currently this includes Synomag-D with plain, NH2, and PEG modified coatings, Perimag, Vivotrax, and Vivotrax Plus. The dataset includes data on particle physical and magnetic properties, like dynamic light scattering, magnetization versus applied field, and zero-field-cooled/field-cooled magnetization measurements, as well as direct evaluations of tracer MPI performance as measured through RELAX and 2D scans on a Magnetic Insight MOMENTUM imager. A table of relevant particle properties is additionally provided as a summary of the processed measurement data for researchers to evaluate directly. All measurements used to generate these values are also provided to allow the evaluation of other analysis methods. Further, this dataset allows for the comparison of several commonly used commercial MPI tracers using a single instrument and consistent procedures. This is useful for researchers aiming to compare performance of newly developed tracers or evaluate the relationship between tracer performance across imaging instruments.
Principal Investigator Contact Information
Carlos M. Rinaldi-Ramos
Institution: University of Florida
Email: carlos.rinaldi@ufl.edu
Alternate Contact Information
Name: Eric Daniel Imhoff
Institution: University of Florida
Email: eimhof@ufl.edu
Dates of Data Collection
Data was collected throughout 2024.
Funding
This work was supported by the National Institute for Biomedical Imaging and Bioengineering under award number R01EB031224.
Data Sources
All data were derived from measurements performed by the authors using the instrumentation described in the methods.
Recommended Citation for the Data Set
Imhoff, Eric D.; Melnyk, Andrii; Rinaldi-Ramos, Carlos M. (2025). Characterization data of commercial tracers for magnetic particle imaging [Dataset]. Dryad. doi: 10.5061/dryad.j3tx95xs0
Related Publications
Imhoff, Eric D.; Melnyk, Andrii; Rinaldi-Ramos, Carlos M. (2025). Characterization and evaluation of commercial tracers for x-space magnetic particle imaging. J. Magn. Magn. Mater.. doi: 10.1016/j.jmmm.2025.172889
List of Abbreviations
- ZFC - Zero-field-cooled
- FC - Field-cooled
- MPI - Magnetic Particle Imaging
- DLS - Dynamic Light Scattering
- SQUID - Superconducting Quantum Interference Device
- FWHM - Full-Width at Half-Maximum
File Descriptions
- The file “Commercial Particle Properties Summary.csv” contains a table of values determined from the data within the repository. This includes hydrodynamic diameter (DH), magnetic diameter (Dm), corresponding lognormal geometric deviation values (lnSigma), magnetic saturation (Ms), iron concentration ([Fe]), intensity in arbitrary units per mass of iron (a.u./mgFe), and full-width at half-maximum (FWHM) for RELAX and 2D measurements in the x and z directions.
- The file “Commercial Particle Volumes and Masses.csv” contains a table of values necessary to determine the mass of iron present in samples for relevant measurements of magnetization (MvH), Zero-field-cooled/field-cooled (ZFCFC), RELAX, and 2D MPI. It includes the tracer name, measured iron concentration, and a volume and calculated mass of iron used in each type of measurement.
- All other files follow a naming scheme separating tokens using the
*character as a delimiter which has the form “TracerName_Measurement_S#*#.csv” - “TracerName” corresponds to the name/ID of the commercial tracer and is consistent with the names inside the summary table (e.g. “Vivotrax”).
- “Measurement” refers to the type of characterization the file corresponds to. These measurements include:
- MvH – csv containing applied field and magnetic moment data.
- zfc – csv file containing temperature and magnetic moment data without an applied magnetic field.
- fc – csv file containing temperature and magnetic moment data with an applied magnetic field of 10 Oe.
- DLS – csv file containing hydrodynamic diameters and corresponding probability density function (pdf) and cumulative distribution function (cdf) values from the intensity-weighted lognormal distribution.
- relax – csv file containing field amplitude and signal for measured point spread function of tracer.
- 2DMPI – dicom (dcm) file containing data from a 2D MPI image.
- The token “S#” refers to a sample number in the case that multiple samples of a tracer were prepared and measured. If not present then only one sample was measured.
- The final suffix “#.csv” or “#.dcm” denote the repeated measurement of a given sample. If not present then only measurement of the sample was performed.
Dynamic Light Scattering
Hydrodynamic diameter measurements of particles diluted in deionized water were obtained at room temperature using a Brookhaven ZetaPALS as an intensity-weighted lognormal distribution.
Iron Concentration Assay
Iron concentration of all tracers was determined by a colorimetric assay using 1,10-phenanthroline. 10 µL of commercial tracers were digested in 1 mL of 70% nitric acid overnight at 101 °C. The following day, 10 µL of the digested sample was placed in a quartz 96-well plate and dried on a hot plate at 115 °C. The plate was transferred into an OT2 liquid handling robot (Opentrons, Long Island City, NY, US) where 46 µL of DI water followed by 30 µL of hydroxylamine hydrochloride (8.06 M) was added and allowed to react for 1 hour. 49 µL of sodium acetate (1.22 M) and 75 µL of 1,10-phenanthroline monohydrate (13 mM) were then added to complex with the Fe2+. Absorbance measurements at 508 nm were collected in a SpectraMax M5 microplate reader (Molecular Devices, San Jose, CA, US). Concentrations were determined using a calibration curve prepared from a TraceCERT iron solution standard for ICP. All samples were prepared and measured in triplicate.
Magnetometry
Magnetization curves for each sample in liquid at 300 K between -7 T and 7 T were collected using a MPMS-3 SQUID magnetometer.
ZFC and FC curves were collected on the same machine with 10 uL of samples dried on cotton. The sample was heated to 400 K then cooled to 4 K before applying a field of 795.8 A/m (10 Oe). The temperature was then ramped 2 to 400 K and cooled back to 4 K while continuously measuring the magnetization at 2 K intervals.
Magnetic Particle Imaging
MPI performance was evaluated by collecting RELAX (45 kHz, 16 mT in the x axis) and 2D (45 kHz, 16/16 mT for x/z axes, 5.7 T/m) scans in standard mode using a MOMENTUM scanner. 3 uL of commercial tracer solutions at stock concentration were loaded into 0.2 mL microcentrifuge tubes or 0.030” ID capillary tubes for RELAX measurements and 2D images, respectively.