Kinetic scheme for Ca2+-arsenazo III interactions.

  title={Kinetic scheme for Ca2+-arsenazo III interactions.},
  author={P. Dorogi and C. Rabl and E. Neumann},
  journal={Biochemical and biophysical research communications},
  volume={111 3},
Temperature-jump relaxation kinetic studies show that the complex formation between Ca2+ and the metallochromic dye arsenazo III (Ar) is associated with a rapid mode (less than or equal to 10 mus-range) involving both Ca2+ and Na+ of the Na-salt of Ar and a slower mode (approximately 10 ms range) which can be attributed to structural rearrangements in the 1:2 complex CaAr2. The kinetic data suggest the scheme: Ca+2Ar = CaAr+Ar = CaAr2 = CaAr2. The relatively slow rate-limiting step sets a limit… Expand
Kinetics and mechanism of Ca2+ binding to arsenazo III and antipyrylazo III.
  • P. Dorogi
  • Chemistry, Medicine
  • Biochimica et biophysica acta
  • 1984
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
Stopped-flow kinetics of the interaction of the fluorescent calcium indicator Quin 2 with calcium ions.
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Spectrophotometric determination of reaction stoichiometry and equilibrium constants of metallochromic indicators. II. The Ca2+-arsenazo III complexes.
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
Purification of arsenazo III, a Ca2+-sensitive dye.
  • N. Kendrick
  • Chemistry, Medicine
  • Analytical biochemistry
  • 1976
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
Calcium transport in human inside-out erythrocyte vesicles.
Inside-out vesicles from human erythrocytes were used to study the kinetics of calcium transport and the data suggest a complex kinetic mechanism. Expand
Transmitter induced calcium entry across the post‐synaptic membrane at frog end‐plates measured using arsenazo III.
1. The Ca2+ influx occurring across the post‐synaptic membrane during transmitter action was studied at the frog neuromuscular junction, using the Ca sensitive dye arsenazo III to monitor theExpand
Changes in the intracellular concentration of free calcium ions in a pace‐maker neurone, measured with the metallochromic indicator dye arsenazo III.
It is suggested that Ca2+ enters during the pace‐maker cycle, thereby increasing [Ca]i, and that this increase is sufficient to activate an outward current carried by K+ ions which causes or contributes to the post‐burst hyperpolarization. Expand
A temperature‐jump apparatus for fluorescence measurements
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however (for it was the literal soul of the life of the Redeemer, John xv. io), is the peculiar token of fellowship with the Redeemer. That love to God (what is meant here is not God’s love to men)Expand
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