Simple new method for labelling of PSMA-11 with Ga-68 in NaHCO3

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F21%3A00542585" target="_blank" >RIV/61389005:_____/21:00542585 - isvavai.cz</a>

Alternative codes found

RIV/68407700:21340/21:00350211

Result on the web

<a href="https://doi.org/10.1016/j.apradiso.2021.109692" target="_blank" >https://doi.org/10.1016/j.apradiso.2021.109692</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.apradiso.2021.109692" target="_blank" >10.1016/j.apradiso.2021.109692</a>

Result language

angličtina

Original language name

Simple new method for labelling of PSMA-11 with Ga-68 in NaHCO3

Original language description

Background: Prostate specific membrane antigen (PSMA) is a type II membrane protein widely expressed on the surface of prostate cancer cells. One of its functions is to act as a receptor mediating the ligand internalization. This PSMA property is employed in the diagnostics and therapy of prostate cancer.nOver the years, small molecules with high affinity for PSMA have been developed and labelled with positron emitters (e.g. Ga-68, F-18, C-11, Cu-64, or Y-86). One of these radiolabelled ligands, [Ga-68] PSMA-11, is one of the most widespread tracers for PET imaging of the prostate cancer.nMany techniques have been proposed and tested for the Ga-68 labelling of PSMA-11. The aim of our work was to design a labelling method of PSMA-11 that minimizes number of the used chemicals and steps, providing quantitative labelling yield at laboratory temperature and may be easily automated.nMethodology: A Ge-68/Ga-68 generator eluate in 0.1 M HCl was loaded on an activated Oasis MCX cartridge, and the cartridge was then thoroughly washed with water. The radionuclide Ga-68 was eluted from the cartridge with 0.1 M NaHCO3 (pH = 8.5, n = 36) or with the same solution with pH adjusted to 7.2-9.0 (n = 38). Precursor PSMA11 was mixed directly with the cartridge eluate of Ga-68 in 0.1 M NaHCO3 of given pH.nFor the stability test, samples of (68)GaPSMA-11 in 0.1 M NaHCO3 (pH 8.5) were mixed in ratio 1 : 1 with the following solutions: 0.1 M NaHCO3 (pH 8.5), human serum, PBS and 0.9% NaCl.nIn order to estimate an effect of the time elapsed between Ga-68 elution from the cartridge in 0.1 M NaHCO3 (pH 8.5) and the labelling onset of PSMA-11, the latter was initiated 0, 5, 10 and 20 min post elution and radio-chemical yield was monitored.nAll the PSMA-11 labelled samples were subjected to radiochemical purity test using HPLC. The whole process starting from generator elution up to HPLC analysis commencement took 10-15 min.nResults: Recovery of Ga-68 from cartridge Oasis MCX using 0.1 M NaHCO3 at pH 8.5 was 71.5 +/- 1.4%. Thirty six PSMA-11 samples (10 mu g in reaction mixture) were labelled at pH 8.5 with total average radiochemical yield of 98 +/- 2%.nRecovery of Ga-68 from cartridge Oasis MCX using 0.1 M NaHCO3 at variable pH of 7.2-9.0 was 62.5 +/- 1.8% showing certain decrease with decreasing pH. A total of 138 samples of PSMA-11 were labelled with Ga-68 at variable pH (7.2-9.0) and four different amounts of PSMA-11 (1, 2.5, 5 and 10 mu g) resulting in the labelling yields of 54.0 +/- 5.3%, 88.2 +/- 3.2%, 99.4 +/- 0.3% and 99.9 +/- 0.1%, respectively. Irrespective of the pH, the radiolabelling yield was quantitative for the molar ratio PSMA-11: Ga-68 > 5000 : 1 in the reaction mixture.nStability tests in 0.1 M NaHCO3 (pH 8.5), human serum, PBS and 0.9% NaCl revealed no observable release of Ga-68 from the Ga-68-PSMA-11 complex within 3 h. Similarly, the delay between the Ga-68 elution from the Oasis MCX cartridge in 0.1 M NaHCO3 (pH 8.5) and start of the labelling of PSMA-11 labelling has no effect on the radiochemical yield.nConclusion: A new method of labelling PSMA-11 ligand with Ga-68 in 0.1 M NaHCO3 using Oasis MCX cartridges was proposed, developed and tested. The results demonstrated that it is rapid, simple, reproducible and easy to automate.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

30224 - Radiology, nuclear medicine and medical imaging

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Applied Radiation and Isotopes

ISSN

0969-8043

e-ISSN

—

Volume of the periodical

172

Issue of the periodical within the volume

JUN

Country of publishing house

GB - UNITED KINGDOM

Number of pages

9

Pages from-to

109692

UT code for WoS article

000640178800030

EID of the result in the Scopus database

2-s2.0-85102860691