Determination of the labeling yield and stability of the complexes Bi-BSA-DOTA and Bi-BSA-DTPA

225Ac/213Bi radionuclide generators for the separation of 213Bi towards clinical demands

“…116 The contribution of the three main types of interaction in the total adsorption process will be dependent on numerous factors, including the pH, the ionic strength, the type of ions, and the introduction of competing or complexing ions and chelators. [39][40][41]69,107,[120][121][122][123][124][125] The desorption mechanism is illustrated when introducing the previously used adsorbents for 225 Ac and 213 Bi separation.…”

“…As explained above, elution with halide ions is typically used to milk 213 Bi owing to the formation of 213 Bi-halide complexes. 43,120,121 Additionally, various chelating agents, such as diethylenetriamine pentaacetate (DTPA) and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), can be used to elute 213 Bi. 107 However, the use of a single column in the separation process poses high requirements on the adsorbents with regard to their high affinity for 225 Ac and a low sorption capacity for 213 Bi complexes to ensure the production of 213 Bi with a high yield and purity.…”

“…Table 1 provides an overview of conditions for 213 Bi eluates and their corresponding labeling conditions from previous research. [39][40][41]69,107,[120][121][122][123][124][125] While the elution occurs at acid pH ( pH < 2), labeling is performed at higher pH values ( pH 4.0-8.4). To bridge this pH gap, a buffer solution (often citrate or acetate) is added, providing the additional benefit of preventing 213 Bi hydrolysis due to weak complexation.…”

“…As explained above, elution with halide ions is typically used to milk 213 Bi owing to the formation of 213 Bi-halide complexes. 43,120,121 Additionally, various chelating agents, such as diethylenetriamine pentaacetate (DTPA) and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), can be used to elute 213 Bi. 107…”

In Vivo Radionuclide Generators for Diagnostics and Therapy

“…This instability is caused by the radiative events that occur during isotopic decay, more specifically the internal conversion of the γ -rays emitted by the nuclide [48]. It has also been shown that direct labeling of DOTA conjugates with 212 Bi is less efficient than other chelators such as diethylenetriaminepentaacetic acid (DTPA) in the presence of other complexing agents such as citric acid [50]. …”