| Title |
[18F]tetrafluoroborate as a PET tracer for the sodium/iodide symporter: the importance of specific activity
|
|---|---|
| Published in |
EJNMMI Research, April 2016
|
| DOI | 10.1186/s13550-016-0188-5 |
| Pubmed ID | |
| Authors |
Alex Khoshnevisan, Maite Jauregui-Osoro, Karen Shaw, Julia Baguña Torres, Jennifer D. Young, Nisha K. Ramakrishnan, Alex Jackson, Gareth E. Smith, Antony D. Gee, Philip J. Blower |
| Abstract |
[(18)F]BF4 (-), the first (18)F-labelled PET imaging agent for the sodium/iodide symporter (NIS), was produced by isotopic exchange yielding a product with limited specific activity (SA, ca. 1 GBq/μmol) posing a risk of sub-optimal target-to-background ratios (TBR) in PET images due to saturation of NIS in vivo. We sought to quantify this risk and to develop a method of production of [(18)F]BF4 (-) with higher SA. A new radiosynthesis of [(18)F]BF4 (-) was developed, involving reaction of [(18)F]F(-) with boron trifluoride diethyl etherate under anhydrous conditions, guided by (11)B and (19)F NMR studies of equilibria involving BF4 (-) and BF3. The SA of the product was determined by ion chromatography. The IC50 of [(19)F]BF4 (-) as an inhibitor of [(18)F]BF4 (-) uptake was determined in vitro using HCT116-C19 human colon cancer cells expressing the human form of NIS (hNIS). The influence of [(19)F]BF4 (-) dose on biodistribution in vivo was evaluated in normal mice by nanoPET imaging and ex vivo tissue counting. An IC50 of 4.8 μΜ was found in vitro indicating a significant risk of in vivo NIS saturation at SA achieved by the isotopic exchange labelling method. In vivo thyroid and salivary gland uptake decreased significantly with [(19)F]BF4 (-) doses above ca. 10 μg/kg. The new radiosynthesis gave high radiochemical purity (>99 %) and moderate yield (15 %) and improved SA (>5 GBq/μmol) from a starting activity of only 1.5 GBq. [(18)F]BF4 (-) produced at previously reported levels of SA (1 GBq/μmol) can lead to reduced uptake in NIS-expressing tissues in mice. This is much less likely in humans. The synthetic approach described provides an alternative for production of [(18)F]BF4 (-) at higher SA with sufficient yield and without need for unusually high starting activity of [(18)F]fluoride, removing the risk of NIS saturation in vivo even in mice. ISRCTN75827286 . |
Mendeley readers
The data shown below were compiled from readership statistics for 35 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Spain | 1 | 3% |
| Unknown | 34 | 97% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 8 | 23% |
| Student > Ph. D. Student | 8 | 23% |
| Student > Master | 6 | 17% |
| Student > Doctoral Student | 3 | 9% |
| Student > Bachelor | 3 | 9% |
| Other | 3 | 9% |
| Unknown | 4 | 11% |
| Readers by discipline | Count | As % |
|---|---|---|
| Chemistry | 14 | 40% |
| Medicine and Dentistry | 6 | 17% |
| Physics and Astronomy | 3 | 9% |
| Engineering | 3 | 9% |
| Pharmacology, Toxicology and Pharmaceutical Science | 1 | 3% |
| Other | 3 | 9% |
| Unknown | 5 | 14% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 25 December 2019.
All research outputs
#7,479,767
of 22,865,319 outputs
Outputs from EJNMMI Research
#141
of 557 outputs
Outputs of similar age
#107,183
of 299,001 outputs
Outputs of similar age from EJNMMI Research
#5
of 17 outputs
Altmetric has tracked 22,865,319 research outputs across all sources so far. This one is in the 44th percentile – i.e., 44% of other outputs scored the same or lower than it.
So far Altmetric has tracked 557 research outputs from this source. They receive a mean Attention Score of 2.5. This one has gotten more attention than average, scoring higher than 69% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 299,001 tracked outputs that were published within six weeks on either side of this one in any source. This one has gotten more attention than average, scoring higher than 55% of its contemporaries.
We're also able to compare this research output to 17 others from the same source and published within six weeks on either side of this one. This one has gotten more attention than average, scoring higher than 70% of its contemporaries.