Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. I. General calculational method.

@article{Dorogi1981SpectrophotometricDO,
  title={Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. I. General calculational method.},
  author={P. Dorogi and E. Neumann},
  journal={Biophysical chemistry},
  year={1981},
  volume={13 2},
  pages={
          117-23
        }
}
A calculational method is developed for spectrophotometric determination of stoichiometrics and individual equilibrium constants in the complexing of metal ions with metallochromic indicators. Implicit expressions are developed for the calculation of all parameters necessary to describe mixtures of 1 : 1, 1 : 2 and 2 : 1 metal-indicator complexes. The analysis of titration curves entails a series of one-variable best-fit determinations based on mass action and conservation laws; this reduction… Expand
10 Citations
Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. II. The Ca2+-arsenazo III complexes.
TLDR
The analytical method described in the preceding article was applied to spectrophotometric Ca2+-titrations of the metallochromic indicator arsenazo III (Ar) and it was determined that Ar forms 1:1,1:2 and 2 : 1 complexes with calcium. Expand
Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. III. Antipyrylazo III complexing with Ca2+ and acetylcholine receptor protein.
TLDR
This is the first reported indication that antipyrylazo III binds to biological material and questions the usefulness of this dye as a Ca indicator in biological systems. Expand
Stoichiometries of arsenazo III-Ca complexes.
TLDR
It is suggested that equilibrium calibration of the dye with calcium cannot be used directly to satisfactorily relate transient absorbance changes in physiological preparations to calcium concentration changes since several stoichiometrically distinct complexes with different absorbances could be formed at different rates. Expand
Arsenazo I and tetramethylmurexide as optical calcium indicators.
Calcium-binding stoichiometry, dissociation equilibrium constants at zero ionic strength @Lo), and molar extinction difference coefficients (At,) at the wavelength )r of the metallochromic indicatorsExpand
Kinetics and mechanism of Ca2+ binding to arsenazo III and antipyrylazo III.
  • P. Dorogi
  • Chemistry, Medicine
  • Biochimica et biophysica acta
  • 1984
TLDR
Dependence of the relaxation rate of arsenazo III on dye and Ca2+ concentrations indicates the presence of both CaAr and CaAr2 complexes, with the Ca Ar2 form being responsible for the slow, 10-20 ms relaxation of this dye. Expand
Kinetic calibration of the calcium indicator arsenazo III. I: Stopped-flow spectroscopy
Abstract Stopped-flow studies of the calcium-arsenazo III (Ar) system exhibit reaction time constants ranging from 4 to 20 ms, mainly caused by the formation of CaAr and CaAr2 complexes ( [ Ca ] 0 =Expand
Calcium Chelators and Calcium Ionophores
The preceding chapters in this volume have demonstrated that Ca ions play critical roles in the regulation of a very large number of physiologic, pharmacologic, and biochemical processes. In theExpand
Calcium channels of the excitable ciliary membrane fromParamecium: An initial biochemical characterization
SummaryA stopped-flow spectrophotometric technique was used to study the kinetics of Ca flux into ciliary membrane vesicles fromParamecium tetraurelia wild-type and several ‘pawn’ mutants withExpand
Cytoplasmic free concentrations of Ca2+ in skeletal muscle cells.
  • M. Konishi
  • Chemistry, Medicine
  • Advances in experimental medicine and biology
  • 2005
Measurement of Ca2+ concentrations in living cells.

References

SHOWING 1-10 OF 15 REFERENCES
Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. II. The Ca2+-arsenazo III complexes.
TLDR
The analytical method described in the preceding article was applied to spectrophotometric Ca2+-titrations of the metallochromic indicator arsenazo III (Ar) and it was determined that Ar forms 1:1,1:2 and 2 : 1 complexes with calcium. Expand
Computer calculation of equilibrium concentrations in mixtures of metal ions and complexing species.
A method is described for calculating equilibrium concentrations of all species in multi-metal-multi-ligand mixtures from the pH of the solution, the total concentration of each metal and eachExpand
Stoichiometry and apparent dissociation constant of the calcium-arsenazo III reaction under physiological conditions.
TLDR
In vitro and in situ tests have been run to characterize the reaction of the mettalochromic indicator, arsenazo III, with calcium, and job plots as well as plots of indicator absorbance show a 1:1 reaction stoichiometry. Expand
A method of estimating the amount of calcium bound to the metallochromic indicator arsenazo III.
  • S. Ohnishi
  • Chemistry, Medicine
  • Biochimica et biophysica acta
  • 1979
TLDR
A new experimental and theoretical method is presented which copes with problems with the high binding constant of arsenazo III for calcium and cannot be determined by the conventional double reciprocal plot. Expand
Arsenazo III forms 2:1 complexes with Ca and 1:1 complexes with Mg under physiological conditions. Estimates of the apparent dissociation constants.
Experiments to determine the apparent dissociation constants of the Ca and Mg complexes of arsenazo III clearly indicated that the predominant Ca complex contains one Ca ion and two dye molecules,Expand
The Art of Titration. From Classical End Points to Modern Differential and Dynamic Analysis
Titration represents the quantitative determination of a chemical change in response to the variation in concentration of a standrad. Information on reaction parameters is usually obtained from anExpand
Purification of arsenazo III, a Ca2+-sensitive dye.
  • N. Kendrick
  • Chemistry, Medicine
  • Analytical biochemistry
  • 1976
TLDR
Methods are described for detection of the colored impurities using DEAE-cellulose thinlayer chromatography in semiorganic solvents, along with methods for purification of the dye using DEae- cellulose column chromatography and Chelex-100 ion-exchange resin. Expand
High and low affinity Ca2+ binding to the sarcoplasmic reticulum: use of a high-affinity fluorescent calcium indicator.
TLDR
A model of the SR is proposed that accounts for several functional properties of the organelle in terms of its known protein composition and topological organization. Expand
...
1
2
...