Adducts of ethylmercury phosphate with amino acids studied by indirect detection of ¹⁹⁹Hg NMR

Applications of heteronuclear NMR spectroscopy in biological and medicinal inorganic chemistry

“…The high affinity of the protein for trivalent metal ions was thought to be responsible for the stabilization of the 3+ oxidation state of the metal. Two distinct 205 Tl NMR signals (at +2075 and +2055 ppm downfield from an aqueous solution of Tl + at infinite dilution) of similar shape were found for the (Tl(III)) 2 -transferrin derivative at physiological pH. The two signals are relatively broad ( ν 1/2 ≈ 100 Hz) and show a different pH dependence (the signal at +2055 ppm was shown to be more resistant to acidification).…”

“…203 Tl and 205 Tl are the only non-quadrupolar NMR-active nuclei in the Group 13 family, and have high receptivities, 203 Tl being only slightly less receptive than 31 P, while 205 Tl, the third most receptive spin I = 1/2 nuclide, is twice as receptive as 31 P. Because of its similarity to the alkali metal ions, Tl + has potential as a probe for Na + and K + in biological systems. Like 27 Al, 205 Tl NMR can be used to investigate directly the specific binding sites of transferrins. Due to its high receptivity, 205 Tl NMR signals of protein-bound Tl ions can be observed even at mM concentrations.…”

“…Like 27 Al, 205 Tl NMR can be used to investigate directly the specific binding sites of transferrins. Due to its high receptivity, 205 Tl NMR signals of protein-bound Tl ions can be observed even at mM concentrations. The first 205 Tl NMR study of human serum transferrin was reported over 20 years ago by Bertini et al [93].…”

“…Due to its high receptivity, 205 Tl NMR signals of protein-bound Tl ions can be observed even at mM concentrations. The first 205 Tl NMR study of human serum transferrin was reported over 20 years ago by Bertini et al [93]. These authors showed that 205 Tl NMR is a convenient probe to monitor the occupancy of the two available transferrins and characterized the dithallium(III)-transferrin and the monothallium derivatives with bicarbonate as synergistic ion.…”

“…The first 205 Tl NMR study of human serum transferrin was reported over 20 years ago by Bertini et al [93]. These authors showed that 205 Tl NMR is a convenient probe to monitor the occupancy of the two available transferrins and characterized the dithallium(III)-transferrin and the monothallium derivatives with bicarbonate as synergistic ion. The high affinity of the protein for trivalent metal ions was thought to be responsible for the stabilization of the 3+ oxidation state of the metal.…”