Aqueous shift reagents for high-resolution cation NMR. V. Thermodynamics of interaction of DyTTHA3- with Na+, K+, Mg 2+, and Ca 2+

Simon C K Chu, Howard Z H Qiu, Charles Jr Springer, Arnold Wishnia

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

Triethylenetetraminehexaacetate complexes of Dy(II) or Tm(III) (DyTTHA3- and TmTTHA3-, introduced as NMR shift reagents for alkali metal cations, Chu et al., J. Magn. Reson. 56, 33 (1984) bind to the four major biological inorganic cations: Na+, K+, Mg2+, and Ca2+. New 23Na and 39K NMR shift displacement data, obtained over wide and different ranges of concentration, were combined with the previous results (including some 25Mg data) for computer analysis. With a proper treatment of the relevant activity coefficients using Pitzer's formulas, it is established that only mono complexes of the shift reagent and a cation need be considered. The cations bind competitively, with nearly identical limiting shifts of 159 and 155 ppm for Na+ and K+; the shift for 25Mg is 3 5 as large. The thermodynamic formation constants for M-LnTTHA are 11 and 18 M-1 with Na+ and K+ (enthalpy of binding, -54 kJ), and 130 and 3100 M-1 with Mg2+ and Ca2+ at 3°C. The results suggest that all the cations bind at the same site, with Mg2+ probably forming a solvent-separated complex. The formation constants expected at 37°C indicate that, at useful shift reagent concentrations, and at physiological cation concentrations, DyTTHA3- can be used not only to distinguish among cation pools but also for quantitative studies of cation relationships. In particular, 23Na signals might be used to report free extracellular Ca2+ concentrations in vivo.

Original languageEnglish (US)
Pages (from-to)287-303
Number of pages17
JournalJournal of Magnetic Resonance (1969)
Volume87
Issue number2
DOIs
StatePublished - 1990
Externally publishedYes

Fingerprint

Cations
Nuclear magnetic resonance
Thermodynamics
Alkali Metals
Activity coefficients
Enthalpy

Cite this

Aqueous shift reagents for high-resolution cation NMR. V. Thermodynamics of interaction of DyTTHA3- with Na+, K+, Mg 2+, and Ca 2+ . / Chu, Simon C K; Qiu, Howard Z H; Springer, Charles Jr; Wishnia, Arnold.

In: Journal of Magnetic Resonance (1969), Vol. 87, No. 2, 1990, p. 287-303.

Research output: Contribution to journalArticle

@article{9b0a95d1eac84281bba8de1c1583907f,
title = "Aqueous shift reagents for high-resolution cation NMR. V. Thermodynamics of interaction of DyTTHA3- with Na+, K+, Mg 2+, and Ca 2+",
abstract = "Triethylenetetraminehexaacetate complexes of Dy(II) or Tm(III) (DyTTHA3- and TmTTHA3-, introduced as NMR shift reagents for alkali metal cations, Chu et al., J. Magn. Reson. 56, 33 (1984) bind to the four major biological inorganic cations: Na+, K+, Mg2+, and Ca2+. New 23Na and 39K NMR shift displacement data, obtained over wide and different ranges of concentration, were combined with the previous results (including some 25Mg data) for computer analysis. With a proper treatment of the relevant activity coefficients using Pitzer's formulas, it is established that only mono complexes of the shift reagent and a cation need be considered. The cations bind competitively, with nearly identical limiting shifts of 159 and 155 ppm for Na+ and K+; the shift for 25Mg is 3 5 as large. The thermodynamic formation constants for M-LnTTHA are 11 and 18 M-1 with Na+ and K+ (enthalpy of binding, -54 kJ), and 130 and 3100 M-1 with Mg2+ and Ca2+ at 3°C. The results suggest that all the cations bind at the same site, with Mg2+ probably forming a solvent-separated complex. The formation constants expected at 37°C indicate that, at useful shift reagent concentrations, and at physiological cation concentrations, DyTTHA3- can be used not only to distinguish among cation pools but also for quantitative studies of cation relationships. In particular, 23Na signals might be used to report free extracellular Ca2+ concentrations in vivo.",
author = "Chu, {Simon C K} and Qiu, {Howard Z H} and Springer, {Charles Jr} and Arnold Wishnia",
year = "1990",
doi = "10.1016/0022-2364(90)90006-U",
language = "English (US)",
volume = "87",
pages = "287--303",
journal = "Journal of Magnetic Resonance (1969)",
issn = "0022-2364",
publisher = "Academic Press Inc.",
number = "2",

}

TY - JOUR

T1 - Aqueous shift reagents for high-resolution cation NMR. V. Thermodynamics of interaction of DyTTHA3- with Na+, K+, Mg 2+, and Ca 2+

AU - Chu, Simon C K

AU - Qiu, Howard Z H

AU - Springer, Charles Jr

AU - Wishnia, Arnold

PY - 1990

Y1 - 1990

N2 - Triethylenetetraminehexaacetate complexes of Dy(II) or Tm(III) (DyTTHA3- and TmTTHA3-, introduced as NMR shift reagents for alkali metal cations, Chu et al., J. Magn. Reson. 56, 33 (1984) bind to the four major biological inorganic cations: Na+, K+, Mg2+, and Ca2+. New 23Na and 39K NMR shift displacement data, obtained over wide and different ranges of concentration, were combined with the previous results (including some 25Mg data) for computer analysis. With a proper treatment of the relevant activity coefficients using Pitzer's formulas, it is established that only mono complexes of the shift reagent and a cation need be considered. The cations bind competitively, with nearly identical limiting shifts of 159 and 155 ppm for Na+ and K+; the shift for 25Mg is 3 5 as large. The thermodynamic formation constants for M-LnTTHA are 11 and 18 M-1 with Na+ and K+ (enthalpy of binding, -54 kJ), and 130 and 3100 M-1 with Mg2+ and Ca2+ at 3°C. The results suggest that all the cations bind at the same site, with Mg2+ probably forming a solvent-separated complex. The formation constants expected at 37°C indicate that, at useful shift reagent concentrations, and at physiological cation concentrations, DyTTHA3- can be used not only to distinguish among cation pools but also for quantitative studies of cation relationships. In particular, 23Na signals might be used to report free extracellular Ca2+ concentrations in vivo.

AB - Triethylenetetraminehexaacetate complexes of Dy(II) or Tm(III) (DyTTHA3- and TmTTHA3-, introduced as NMR shift reagents for alkali metal cations, Chu et al., J. Magn. Reson. 56, 33 (1984) bind to the four major biological inorganic cations: Na+, K+, Mg2+, and Ca2+. New 23Na and 39K NMR shift displacement data, obtained over wide and different ranges of concentration, were combined with the previous results (including some 25Mg data) for computer analysis. With a proper treatment of the relevant activity coefficients using Pitzer's formulas, it is established that only mono complexes of the shift reagent and a cation need be considered. The cations bind competitively, with nearly identical limiting shifts of 159 and 155 ppm for Na+ and K+; the shift for 25Mg is 3 5 as large. The thermodynamic formation constants for M-LnTTHA are 11 and 18 M-1 with Na+ and K+ (enthalpy of binding, -54 kJ), and 130 and 3100 M-1 with Mg2+ and Ca2+ at 3°C. The results suggest that all the cations bind at the same site, with Mg2+ probably forming a solvent-separated complex. The formation constants expected at 37°C indicate that, at useful shift reagent concentrations, and at physiological cation concentrations, DyTTHA3- can be used not only to distinguish among cation pools but also for quantitative studies of cation relationships. In particular, 23Na signals might be used to report free extracellular Ca2+ concentrations in vivo.

UR - http://www.scopus.com/inward/record.url?scp=0000030322&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000030322&partnerID=8YFLogxK

U2 - 10.1016/0022-2364(90)90006-U

DO - 10.1016/0022-2364(90)90006-U

M3 - Article

AN - SCOPUS:0000030322

VL - 87

SP - 287

EP - 303

JO - Journal of Magnetic Resonance (1969)

JF - Journal of Magnetic Resonance (1969)

SN - 0022-2364

IS - 2

ER -