A Novel Facile Method of Labeling Octreotide with ¹⁸F-Fluorine

Imaging of Human Epidermal Growth Factor Receptor Type 2 Expression with 18F-Labeled Affibody Molecule ZHER2:2395 in a Mouse Model for Ovarian Cancer

“…Radiolabeling with 18 F was based on the complexation of Al 18 F by NOTA as described elsewhere (23,24). Briefly, a Chromafix PS-HCO 3 cartridge (ABX) with 2-6 GBq of 18 F (BV Cyclotron VU) was washed with 3 mL of metal-free water.…”

“…However, this labeling reaction required a long synthesis time. Lately, a new method was described for labeling of NOTA-conjugated peptides with 18 F, which is based on the formation of aluminum 18 F-fluoride (Al 18 F) and its complexation by NOTA (23,24). This method allows rapid and efficient labeling of peptides and proteins with 18 F.…”

Targeting Somatostatin Receptors: Preclinical Evaluation of Novel 18F-Fluoroethyltriazole-Tyr3-Octreotate Analogs for PET

“…Peptides labeled with the 18 F radioisotope, having the optimal combination of half-life, photon flux, and photon energy (1.8-h half-life, 97% b 1 , 0.6-MeV E b1 ), should be superior to the metal-based tracers and be devoid of nonspecific uptake resulting from transchelation (17). Consequently, 18 F-labeled octreotide analogs have previously been developed (18)(19)(20). Tyr 3 -octreotate has been radiolabeled with both 68 Ga and 18 F radioisotopes for PET of tumors (21,22).…”

“…Rapid tumor accumulation, together with rapid clearance of labeled peptides from normal tissues including the liver and muscle, is a prerequisite for use of short-lived positron-emitting radioisotopes such as 18 F. Recognizing that incorporation of polyethylene glycol (PEG) moiety and length or type of linker used to connect the peptide core to the 18 F-containing prosthetic group can change peptide disposition, we performed a comparative study to evaluate tissue pharmacokinetics and imaging properties of 5 structurally related 18 F-fluoroethyltriazole-Tyr 3 -octreotate (FET-TOCA) analogs-FET-G-PEG-TOCA, FETE-PEG-TOCA, FET-G-TOCA, FETE-TOCA, and FET-bAG-TOCA (Fig. 1)and compared these to a scrambled labeled peptide, the recently described 18 F-aluminum fluoride NOTA-octreotide ( 18 F-AIF-NOTA-OC (19)) and the clinically used radiotracer 68 Ga-DOTATATE. Assessment of the pharmacokinetics and imaging properties in vivo should provide structure-activity relationship data for selection of the optimal radiotracer.…”

Current Molecular Imaging Positron Emitting Radiotracers in Oncology

“…64 Cu-or 68 Ga-DOTA-conjugated OC showed greater imaging potential than 111 In or 99m Tc-labeled OC [138]. [140]. Taken together, OC PET showed great sensitivity and accuracy for imaging neuroendocrine tumors, especially in detecting metastatic tumors (lymph node, bone, and liver), thus permitting more accurate disease staging.…”