Comparative studies on the biospeciation of antidiabetic VO(IV) and Zn(II) complexes

Development of the application of speciation in chemistry

“…A minor amount (<5%) of Zn(II) was still coordinated with the original carrier (or other buffer components), but no Zn(II) was bound by Tf [34]. Thus, the results of modeling calculations (see above) were confirmed experimentally by CZE-ICP-MS and by ultrafiltration-ICP-atomic emission spectroscopy [70] studies.…”

“…This approach was employed to obtain simulations of the serum distribution of various insulin-enhancing V(IV) [33,68,69] and Zn(II) complexes (see Section 4.3.1) [70]. In the ideal case, the calculated results can be confirmed by separation methods or structure elucidation techniques [70].…”

“…Modeling calculations can determine the detailed distributions of metal ions among the LMM and HMM components of serum. Various separation techniques such as ultrafiltration [70] and capillary zone electrophoresis inductively coupled plasma MS (CZE-ICP-MS) [34] have been employed in the fractionation of different LMM and HMM fractions to confirm the basic findings of the modeling calculations, e.g., the distribution of Zn(II)-dipic complexes in serum systems (0.1 mM, serum diluted with buffer: 1:4, 24 h incubation at 25C), where most of the Zn(II) was bound to HSA, although a minor amount of Zn(II) was bound to dipic, whereas no Zn(II) was bound to Tf (Fig. 3).…”

“…100 M level [159]. The potential interactions of drug candidate complexes in the serum with LMM components have been studied in detail by pH-potentiometry [34,70] based on modeling calculations of these binders (without the HMM components) with His and Cys, and their ternary complexes as primary Zn(II) binders.…”

Speciation of Metal Complexes of Medicinal Interest: Relationship between Solution Equilibria and Pharmaceutical Properties

“…Zn(pic) 2 ; Zn(maltolato) 2 Zn(dhp) 2 and Zn(dipic) 2 ) having insulin-enhancing activity in the concentration range of 100 mM level [1]. The possible interactions of the drug candidate complexes in blood with the LMM components were studied by pH-potentiometry in details [140,141], based on modeling calculation among these binders (without the HMM components) His and Cys and their ternary complexes are the primary Zn(II) binders [142].…”