A computer program for determination of equilibrium constants and binding site concentrations in radioimmunoassay systems

In contrast to the adjustment of single plates a block adjustment is a simultaneous determination of all unknowns associated with many overlapping plates (star positions and plate constants etc. ) by one large adjustment. This plate overlap technique was introduced by Eichhorn and reviewed by Googe et. al. The author now has developed a set of computer programmes which allows the adjustment of any set of contemporaneous overlapping plates. There is in principle no limit for the number of plates, the number of stars, the number of individual plate constants for each plate, and for the overlapping factor.

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Antithrombin-mediated Inhibition of Factor Vlla-Tissue Factor Complex by the Synthetic Pentasaccharide Representing the Heparin Binding Site to Antithrombin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650512 ◽

1996 ◽

Vol 76 (01) ◽

pp. 005-008 ◽

Cited By ~ 22

Author(s):

Jean Claude Lormeau ◽

Jean Pascal Herault ◽

Jean Marc Herbert

Keyword(s):

Binding Site ◽

Tissue Factor ◽

Residual Activity ◽

Coagulation Factors ◽

Heparin Binding ◽

Experimental Conditions ◽

First Order ◽

Heparin Binding Site ◽

Coagulant Activity

SummaryWe examined the effect of the synthetic pentasaccharide representing the minimal binding site of heparin to antithrombin on the antithrombin-mediated inactivation of factor Vila bound to tissue factor. This effect was compared to the effect of unfractionated heparin. Using purified recombinant human coagulation factors and either a clotting or an amidolytic assay for the determination of the residual activity of factor Vila, we showed that the pentasaccharide was an efficient antithrombin-dependent inhibitor of the coagulant activity of tissue factor-factor Vila complex. In our experimental conditions, assuming a mean MW of 14,000 for heparin, the molar pseudo-first order rate constants for ATIII-mediated FVIIa inhibition by ATIII-binding heparin and by the synthetic pentasaccharide were found to be similar with respective values of 104,000 ± 10,500 min-1 and 112,000 ± 12,000 min-1 (mean ± s.e.m., n = 3)

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Comparative assessment of informational content of the equations of F.P. Hadlock and the computer program of V.N. Demidov in determination of term of gestation and fetal weight in the III trimester of gestation

10.21516/2413-1458-2017-16-2-145-150 ◽

2017 ◽

Author(s):

E.A. Derkach , O.I. Guseva

Keyword(s):

Computer Program ◽

High Precision ◽

Gestational Age ◽

Computer Programs ◽

Comparative Assessment ◽

Fetal Weight ◽

Informational Content ◽

Third Trimester ◽

The Third

Objectives: to compare the accuracy of equations F.P. Hadlock and computer programs by V.N. Demidov in determining gestational age and fetal weight in the third trimester of gestation. Materials: 328 patients in terms 36–42 weeks of gestation are examined. Ultrasonography was performed in 0–5 days prior to childbirth. Results: it is established that the average mistake in determination of term of pregnancy when using the equation of F.P. Hadlock made 12,5 days, the computer program of V.N. Demidov – 4,4 days (distinction 2,8 times). The mistake within 4 days, when using the equation of F.P. Hadlock has met on average in 23,1 % of observations, the computer program of V.N. Demidov — 65,9 % (difference in 2,9 times). The mistake more than 10 days, took place respectively in 51,7 and 8,2 % (distinction by 6,3 times). At a comparative assessment of size of a mistake in determination of fetal mass it is established that when using the equation of F.P. Hadlock it has averaged 281,0 g, at application of the computer program of V.N. Demidov — 182,5 g (distinction of 54 %). The small mistake in the mass of a fetus which isn't exceeding 200 g at application of the equation of F.P. Hadlock has met in 48,1 % of cases and the computer program of V.N. Demidov — 64,0 % (distinction of 33,1 %). The mistake exceeding 500 g has been stated in 18 % (F.P. Hadlock) and 4,3 % (V.N. Demidov) respectively (distinction 4,2 times). Conclusions: the computer program of V.N. Demidov has high precision in determination of term of a gestation and mass of a fetus in the III pregnancy.

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Spectrophotometric study of the complexation equilibria of cadmium ions with 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-diethylaminophenol (BrPADAP, ClPADAP)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19830052 ◽

1983 ◽

Vol 48 (1) ◽

pp. 52-59 ◽

Cited By ~ 4

Author(s):

Vlastimil Kubáň ◽

Miroslav Macka

Keyword(s):

Equilibrium Constants ◽

Spectrophotometric Study ◽

Graphical Analysis ◽

Optimal Conditions ◽

Cadmium Ions ◽

Brij 35 ◽

Ethanol Medium ◽

Triton X ◽

Derivatives Of

The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the reactions of formation of the ML and ML2 complexes of both reagents with cadmium(II) ions were determined by graphical analysis and numerical interpretation of the absorbance-pH curves by the modified SQUAD-G program. Optimal conditions were proposed for the spectrophotometric determination of Cd in 10% v/v ethanol medium in the presence of 0.1% w/v Triton X-100 or 1% w/v Brij 35. BrPADAP and ClPADAP are the most sensitive spectrophotometric reagents for the determination of cadmium(II) ions (ε = 1.28-1.44 . 105 mmol-1 cm2 at 560 nm and pH 8.0-9.5) with a high colour contrast in the reaction (Δλmax ~117 nm) and a selectivity similar to that of other N-heterocyclic azodyes (PAR, PAN, etc.).

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Spectrophotometric study of the acid-base and optical properties of the 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-(diethylamino)phenol (BrPADAP, ClPADAP) and their complexation equilibria with zinc(II) ions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822676 ◽

1982 ◽

Vol 47 (10) ◽

pp. 2676-2691 ◽

Cited By ~ 6

Author(s):

Miroslav Macka ◽

Vlastimil Kubáň

Keyword(s):

Equilibrium Constants ◽

Spectrophotometric Study ◽

Graphical Analysis ◽

Alkaline Media ◽

Acid Base ◽

Ethanol Medium ◽

Triton X ◽

Mixed Water ◽

Derivatives Of

The optical and acid-base characteristics of BrPADAP and ClPADAP were studied in mixed water-ethanol and water-DMF media and in 10% ethanol medium in the presence of cationic, anionic and nonionic tensides. The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the ML and ML2 complexes with zinc(II) ions were found by graphical analysis and numerical interpretation of the absorbance curves by the modified SQUAD-G program. Optimal conditions were found for the spectrophotometric determination of Zn(II) in the presence of 0.1% Triton X-100 or 1% Brij 35 in alkaline media with pH = 6.5-10. BrPADAP and ClPADAP are the most sensitive reagents (ε = 1.3-1.6 . 105 mmol-1 cm2 at 557 and 560 nm, respectively) for the determination of zinc with high colour contrast of the reaction (Δλ = 104 nm) and selectivity similar to that for the other N-heterocyclic azodyes (PAN, PAR, etc.).

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Recognition of hydrogen isotopomers by an open-cage fullerene

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2011.0629 ◽

2013 ◽

Vol 371 (1998) ◽

pp. 20110629 ◽

Cited By ~ 4

Author(s):

Yasujiro Murata ◽

Shih-Ching Chuang ◽

Fumiyuki Tanabe ◽

Michihisa Murata ◽

Koichi Komatsu

Keyword(s):

Equilibrium Constants ◽

Equilibrium Mixture ◽

Size Difference ◽

Binding Affinities ◽

Kinetic Isotope ◽

Molecular Sizes ◽

Lower Temperature ◽

Kinetics Of ◽

Pressure Hydrogen

We present our study on the recognition of hydrogen isotopes by an open-cage fullerene through determination of binding affinity of isotopes H 2 /HD/D 2 with the open-cage fullerene and comparison of their relative molecular sizes through kinetic-isotope-release experiments. We took advantage of isotope H 2 /D 2 exchange that generated an equilibrium mixture of H 2 /HD/D 2 in a stainless steel autoclave to conduct high-pressure hydrogen insertion into an open-cage fullerene. The equilibrium constants of three isotopes with the open-cage fullerene were determined at various pressures and temperatures. Our results show a higher equilibrium constant for HD into open-cage fullerene than the other two isotopomers, which is consistent with its dipolar nature. D 2 molecule generally binds stronger than H 2 because of its heavier mass; however, the affinity for H 2 becomes larger than D 2 at lower temperature, when size effect becomes dominant. We further investigated the kinetics of H 2 /HD/D 2 release from open-cage fullerene, proving their relative escaping rates. D 2 was found to be the smallest and H 2 the largest molecule. This notion has not only supported the observed inversion of relative binding affinities between H 2 and D 2 , but also demonstrated that comparison of size difference of single molecules through non-convalent kinetic-isotope effect was applicable.

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Determination of the binding site size of hexaammineruthenium(iii) inside monolayers of DNA on gold

The Analyst ◽

10.1039/d0an01685c ◽

2021 ◽

Author(s):

Alireza Abi ◽

Afsaneh Safavi

Keyword(s):

Metal Complex ◽

Binding Site ◽

Dna Strands

Hexaammineruthenium(iii) metal complex can bind to surface-tethered DNA strands in excess of what is required for the compensation of the DNA charges.

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