68Ga-DOTA and analogs: Current status and future perspectives

Abstract

The construction of the Ge/Ga generator has increased application of radiopharmaceuticals labeled with this isotope in medicine. Ga-PET is widely employed in the management of neuroendocrine tumors but favorable chemistry with tri- and tetraaza-ring molecules has opened wide range ofGa application in other fields of PET imaging. This review covers the radiopharmaceuticals labeled with gallium in molecular imaging and shows perspectives on the use of gallium-68 as a substitute for technetium-99, fluorine-18 and carbon-11 in some applications.

The potential of radiolabeled chemotherapeutics in tumor diagnosis: Preliminary investigations with 68Ga‐gemcitabine

“…Variation of pH of the reaction mixture revealed that the maximum radiochemical yield could be obtained when the pH of the reaction mixture was maintained between 4 and 5. This is in agreement with the reported value of pH required for labeling of DOTA or its derivatives with 68 Ga (Bhadwal et al, ; Burke et al, ; Kilian, ; Martiniova et al, ). The effect of incubation time and temperature on the complexation yield revealed that approximately 20 min of incubation in a boiling water bath is required to prepare the agent with near quantitative yield.…”

“…As direct incorporation of 68 Ga in gemcitabine moiety (Figure A) is difficult, radiolabeling was attempted through a bi‐functional chelating agent (BFCA). DOTA (1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) can be used as a suitable BFCA for developing 68 Ga‐based agents for radiodiagnostic applications (Burke, Clemente, & Archibald, ; Kilian, ; Martiniova, De Palatis, Etchebehere, & Ravizzini, ). Therefore, for the present study p ‐NCS‐benzyl‐DOTA [2,2′,2″‐(10‐(1‐carboxy‐4‐((4‐isothiocyanatobenzyl) amino)‐4‐oxobutyl)‐1,4,7,10‐tetraazacyclododecane‐1,4,7‐triyl)‐triacetic acid] was chosen as the BFCA to couple with gemcitabine.…”

“…(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) can be used as a suitable BFCA for developing 68 Ga-based agents for radiodiagnostic applications (Burke, Clemente, & Archibald, 2014;Kilian, 2014;Martiniova, De Palatis, Etchebehere, & Ravizzini, 2016). Therefore, for the present study p-NCS-benzyl-DOTA [2,2 0 ,2 00 -(10-(1-carboxy-4-((4isothiocyanatobenzyl) amino)-4-oxobutyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)-triacetic acid] was chosen as the BFCA to couple with gemcitabine.…”

Antibody Fragment and Affibody ImmunoPET Imaging Agents: Radiolabelling Strategies and Applications

“…[66][67][68] Recently,s horter-lived radiometalss uch as 68 Ga (t1 = 2 = 67.7 min) and 44 Sc (t1 = 2 = 3.9 h), with half-lives more closely matching the pharmacokinetics of antibodyf ragments, have garnered closer attention for fragment labelling. 68 Ga is particularly convenient for radiolabelling because it is produced via a 68 Ge/ 68 Ga generatora nd thusc ircumventst he need (and associated costs) of ac yclotron facility.Ac ommon approach for 68 Ga-labelled is reaction with the widely used DOTAa nd NOTA, [69] however,arange of other bifunctional chelators have been investigated. [70] The FDA approved 68 GaDOTA-TATEt racer for somatostatin receptor positive neuroendocrine tumours is an example of its growing importance for clinicalu se.…”

The next generation of medical physicists

“…Readers will also find two papers related to nuclear medicine. In the first paper, 3 Krzysztof Kilian describes the current status and future perspectives of 68a-DOTA and analogs. This topic is relevant to all involved in nuclear medicine.…”