A comparative thermodynamic study of the formation of scandium complexes with DTPA and DOTA

Abstract

The complexation of scandium(iii) by various polyaminopolycarboxylic ligands (DTPA and DOTA) was studied by capillary electrophoresis with ICP-MS detection in 0.1 mol L−1 NaCl ionic strength solutions at 25 °C.

AAZTA: An Ideal Chelating Agent for the Development of 44Sc PET Imaging Agents

“…44 Sc can be conveniently produced by the 44 Ti/ 44 Sc generator, [7][8][9] overcoming the dependence on expensive accelerators.T od ate,alimited number of studies have been devoted to the coordination chemistry of this metal ion, [10,11] although the importance of scandium is further stressed by the existence of other isotopes ( 43 Sc, 44m Sc, and 47 Sc) of potential interest in nuclear medicine,e specially for theranostic applications. [12] DOTA( Scheme 1) and its derivatives are still the workhorse for the preparation of stable chelates, but their slow formation kinetics requires long reaction times at 70-95 8 8C, which is hardly compatible with the labeling of antibodies and other biomolecules. [13][14][15] NOTA [16] and selected acyclic ligands (for example,D TPA, [17] EGTA, [17] CHX-A"-DTPA [18] )b ind Sc 3+ more rapidly than DOTA, but with am arkedly reduced stability of the corresponding chelates.…”

Thermodynamic and Kinetic Features of Bi3+ Complexes with the Azamacrocycles H4BATA and H4DOTA

“…[35] The H 4 DOTA ligand is known to form stable complexes with both Na + and K + . [25] Thus, according to our experimental data, the stability constant of [BiDOTA] À was corrected by a value of log(1 + K KDOTA [K + ]) [23] because of the application of KNO 3 as a supporting electrolyte. The final values of the stability constant are presented in Table 1.…”

“…Hence, the conditional stability constant thus obtained is related to the [BiDOTA] À form. For H 4 DOTA, various sets of protonation constants have been presented in the literature, [11,12,14,23] determined by the influence of the alkali metal ions of the background electrolytes as well as by the application of different methods for calculating the constants.…”

Production of scandium radionuclides for theranostic applications: towards standardization of quality requirements

“…HCl, 25°C) was much slower than that for [Ln(dota)] − complexes (Pniok et al 2014). Therefore, DOTA and its derivatives were assumed to be very suitable ligands for scandium radioisotopes (Pniok et al 2014;Huclier-Markai et al 2015).…”