Gamma-ray spectrometric measurement of radionuclide purity of radiopharmaceuticals contained in bottle samples

The radionuclide purity of a radiopharmaceutical product is usually measured by gamma-ray spectrometry with various measurement geometries. The importance of this test is that the radionuclide impurities, if present, result in an increase in the radiation dose to the patient without contributing to diagnostic information and in some cases may also interfere with the marking molecules and affect the proper conduct of diagnostic examination. In this work, gamma-ray spectrometry is used to determine the amounts of impurities by adopting as measurement geometry the same bottle containing eluted or prepared radiopharmaceuticals. In addition to high-purity germanium semiconductor detectors, the usefulness of NaI(Tl) and LaBr3(Ce) scintillators in routine operation is also examined. For the latter detectors, an evaluation of the minimum detectable activity was carried out and compared with the activity limits established by the regulation rules. The main cases considered are related to the first elution of 99Mo-99mTc generators and samples of 18F-FDG (fluoro-deoxy-glucose) to be used for positron emission tomography diagnostics.

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Characterization of 41Ar production in air at a PET cyclotron facility

Modern Physics Letters A ◽

10.1142/s0217732317400144 ◽

2017 ◽

Vol 32 (17) ◽

pp. 1740014 ◽

Cited By ~ 2

Author(s):

Gianfranco Cicoria ◽

Francesco Cesarini ◽

Angelo Infantino ◽

Sara Vichi ◽

Federico Zagni ◽

...

Keyword(s):

Gamma Ray ◽

Ventilation System ◽

Emission Tomography ◽

Gamma Ray Spectrometry ◽

Maximum Value ◽

Positron Emission ◽

Before And After ◽

Surrounding Areas ◽

Total Effective Dose

In the production of Positron Emission Tomography (PET) nuclides at a medical cyclotron facility [Formula: see text]Ar (T[Formula: see text] = 109.34 m) is produced by the activation of air due to the neutron flux, according to the [Formula: see text]Ar(n, [Formula: see text])[Formula: see text]Ar reaction. In this work, we describe a relatively inexpensive and readily reproducible methodology of air sampling that can be used for quantification of [Formula: see text]Ar during the routine production of PET nuclides. We report the results of an extensive measurement campaign in the cyclotron bunker and in the ducts of the ventilation system, before and after final filtering of the extracted air. Air Samples were analyzed using a gamma-ray spectrometry system equipped with HPGe detector, with proper correction of the efficiency calibration to account for the samples density. The results of measurement were then used to evaluate the Total Effective Dose (TED) to the population living in the surrounding areas, due to routine emissions in the operation of the cyclotron. The average [Formula: see text]Ar saturation yield per one liter of air emitted in the environment resulted to be (0.044 ± 0.007) Bq/([Formula: see text]A ⋅ dm3). The maximum value of TED for the critical group of the population, even considering an overestimated workload, was less than 0.19 [Formula: see text]Sv/year, well below the level of radiological relevance.

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Carbon Nanomaterials for Sorption of 68Ga for Potential Using in Positron Emission Tomography

Nanomaterials ◽

10.3390/nano10061090 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1090

Author(s):

Andrey G. Kazakov ◽

Bogdan L. Garashchenko ◽

Milana K. Ivanova ◽

Sergey E. Vinokurov ◽

Boris F. Myasoedov

Keyword(s):

Positron Emission Tomography ◽

Photoelectron Spectroscopy ◽

Carbon Nanomaterials ◽

Gamma Ray ◽

The Body ◽

Emission Tomography ◽

Gamma Ray Spectrometry ◽

Sorption Behavior ◽

Chemical Compositions ◽

Positron Emission

In present work, carbon nanomaterials (CNMs) are investigated as potential carriers of 68Ga, which is widely used in positron emission tomography (PET) in nuclear medicine. Sorption behavior of 68Ga was studied onto CNMs of various structures and chemical compositions: nanodiamonds (ND), reduced graphite oxide (rGiO) and multi-walled carbon nanotubes (MWCNT), as well as their oxidized (ND–COOH) or reduced (rGiO–H, MWCNT–H) forms. The physicochemical properties of the nanoparticles were determined by high resolution transmission electron microscopy, x-ray photoelectron spectroscopy, dynamic light scattering and potentiometric titration. The content of 68Ga in the solutions during the study of sorption was determined by gamma-ray spectrometry. The highest degree of 68Ga sorption was observed on ND and ND–COOH samples, and the optimal sorption conditions were determined: an aqueous solution with a pH of 5–7, m/V ratio of 50 μg/mL and a room temperature (25 °C). The 68Ga@ND and 68Ga@ND–COOH conjugates were found to be stable in a model blood solution—phosphate-buffered saline with a pH of 7.3, containing 40 g/L of bovine serum albumin: 68Ga desorption from these samples in 90 minutes was no more than 20% at 25 °C and up to 30% at 37 °C. Such a quantity of desorbed 68Ga does not harm the body and does not interfere with the PET imaging process. Thus, ND and ND–COOH are promising CNMs for using as carriers of 68Ga for PET diagnostics.

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Direct conversion semiconductor detectors in positron emission tomography

Modern Physics Letters A ◽

10.1142/s0217732315300116 ◽

2015 ◽

Vol 30 (14) ◽

pp. 1530011 ◽

Cited By ~ 2

Author(s):

Joshua W. Cates ◽

Yi Gu ◽

Craig S. Levin

Keyword(s):

Positron Emission Tomography ◽

Direct Detection ◽

Direct Conversion ◽

Image Resolution ◽

Emission Tomography ◽

Semiconductor Detectors ◽

Ongoing Research ◽

Tumor Delineation ◽

Positron Emission ◽

Quantitative Accuracy

Semiconductor detectors are playing an increasing role in ongoing research to improve image resolution, contrast, and quantitative accuracy in preclinical applications of positron emission tomography (PET). These detectors serve as a medium for direct detection of annihilation photons. Early clinical translation of this technology has shown improvements in image quality and tumor delineation for head and neck cancers, relative to conventional scintillator-based systems. After a brief outline of the basics of PET imaging and the physical detection mechanisms for semiconductor detectors, an overview of ongoing detector development work is presented. The capabilities of semiconductor-based PET systems and the current state of these devices are discussed.

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Radionuclide purity assessment and calibration of 90Y(177Lu) glass particles using gamma-ray spectrometry

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-011-1450-y ◽

2011 ◽

Vol 292 (1) ◽

pp. 429-434

Author(s):

H. Poorbaygi ◽

Sh. Sheibani ◽

S. M. R. Aghamiri ◽

M. Azizi Shamami

Keyword(s):

Gamma Ray ◽

Gamma Ray Spectrometry ◽

Purity Assessment ◽

Radionuclide Purity

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Recent Advances in Ceramic Scintillators

MRS Proceedings ◽

10.1557/proc-1038-o06-02 ◽

2007 ◽

Vol 1038 ◽

Cited By ~ 1

Author(s):

Edgar Van Loef ◽

Yimin Wang ◽

Jarek Glodo ◽

Charles Brecher ◽

Alex Lempicki ◽

...

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Medical Imaging ◽

Atomic Number ◽

Gamma Ray ◽

Light Yield ◽

Emission Tomography ◽

Imaging Modalities ◽

Practical Application ◽

Positron Emission

AbstractA review is presented of recent ceramic scintillator R&D. Attention is focussed on Ce doped gamma-ray scintillators for medical imaging applications. Ceramic scintillators discussed in detail include SrHfO3:Ce and Lu2Hf2O7:Ce. These materials combine a high density and high atomic number with fast emission and a good light yield and may find practical application in medical imaging modalities such as Positron Emission Tomography and Computed Tomography.

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