Computation of solution equilibria: a guide to methods in potentiometry, extraction and spectrophotometry

Meloun, Milan; Havel, Josef; Högfeldt, Erik; Chipperfield, J. R.

doi:10.1016/s0003-2670(00)85305-2

Cited by 43 publications

(20 citation statements)

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“…36 We opted to use a program called DIMER-K D , written by us several years ago to fit data with a dimerization model 9 (the program utilizes the algorithm by Horman and co-workers 10 ). When dealing with multiple equilibria we used the program called Dynafit version 3.…”

Section: Methodsmentioning

confidence: 99%

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Kotzé

Gerber

et al. 2013

Dalton Trans.

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Section: Methodsmentioning

confidence: 99%

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Kotzé

Gerber

et al. 2013

Dalton Trans.

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“…More information about calculational procedures can be found in the books by LEGGETT 12 and by MELOUN et al 13 In particular, an implementation of this type of calculation in a program called SQUAD (stability quotients from absorbance data) is available in LEGGETT'S book. In practice, it is found that the absorbance data must have little experimental error and the fact that desired parameters, epq r and ~pqr appear as multiplication product parameters in the regression make these calculations quite unstable.…”

Section: Resultsmentioning

confidence: 99%

Applications of laser photoacoustic spectroscopy using an optical parametric oscillator to the study of complexation equilibria in dilute aqueous solutions

Kinard

Hunter

Clark

1998

J Radioanal Nucl Chem

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A 30 Hz YAG laser pumped, narrow-line, optical parametric oscillator (OPO) has been used to investigate the chemical states of selected compounds in aqueous solution. The OPO system has the advantage that it can scan wavelengths over large ranges without significant loss of output power. The visible spectra of rare earth complexes in dilute aqueous solutions (as chemical analogs for the actinides) have been studied and preliminary qualitative results for erbium acetate complexes at the 100 micromolar level are in good agreement with literature data. Quantitative measurements of the protonation constant for phenol red at the 100 nanomolar level were measured. The particular implementation of the OPO system used in this work introduced a number of spectral artifacts due to optical signal overlap with near-infrared water absorption bands. In addition, it was demonstrated that the concentration limiting factor for photoacoustic spectroscopy is the intrinsic absorption of water in the visible region of the spectrum.

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“…page 101 in ref. [36]. The statistics of residuals can be used for a numerical goodnessof-fit evaluation, cf.…”

Section: Discussionmentioning

confidence: 99%

“…The experimental and computation scheme to determine the dissociation constants of the multi-component system is taken from Meloun et al [36] and the five steps are described in details [16].…”

Section: Apparatus and Proceduresmentioning

confidence: 99%

The Thermodynamic Overlapping pKa of the Antitumor Drug Ibrutinib Using Multiwavelength UV/VIS-Spectroscopy and Potentiometry

Meloun¹,

Mikešová²,

Pekárek³

et al. 2017

JAPLR

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Potentiometric and spectrophotometric pH-titrations of the antitumor drug Ibrutinib for dissociation constants determination were compared. Ibrutinib is targeting B-cell malignancies, for treatment of chronic lymphocytic leukemia, and Waldenström's macroglobulinemia. Chemometrics approach to the nonlinear regression of the pH-spectra (REACTLAB, SQUAD84) and pH-titration (ESAB) determines four dissociation constants. Ibrutinib exhibits four protonatable centers in a pH range of 2 to 10, where only two pK are well separated (ΔpK > 3), while the others are near dissociation constants of overlapping equilibria. The molecule LH 2 can protonate to sparingly soluble cations LH3+ and LH42+ and dissociate to anions LH -and L 2-. The set of spectra for pH from 2 to 11 in 220 to 300nm exhibits chromophore sensitivity to a pH change. Since pH above 10 and pH below 5 occurs in a titrated solution of a very fine precipitate of Ibrutinib, this part of the potentiometric titration curve pH over 10 and pH below 5 did not undergo regression analysis to estimate pK a´s . Depending on ionic strength the thermodynamic dissociation constants were estimated at 25°C and 37°C: pK a1 T = 3.22 and 3.22, pK a2 T = 4.17 and 5.21, pK a3 T = 6.77 and 6.77, pK a4 T = 9.82 and 9.81. Keywords:

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Computation of solution equilibria: a guide to methods in potentiometry, extraction and spectrophotometry

Cited by 43 publications

References 0 publications

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Applications of laser photoacoustic spectroscopy using an optical parametric oscillator to the study of complexation equilibria in dilute aqueous solutions

The Thermodynamic Overlapping pKa of the Antitumor Drug Ibrutinib Using Multiwavelength UV/VIS-Spectroscopy and Potentiometry

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Computation of solution equilibria: a guide to methods in potentiometry, extraction and spectrophotometry

Cited by 43 publications

References 0 publications

Cation–π induced aggregation of water-soluble [PtII(diimine)(Ln-S,O)]+complexes studied by1H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Cation–π induced aggregation of water-soluble [PtII(diimine)(Ln-S,O)]+complexes studied by1H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Applications of laser photoacoustic spectroscopy using an optical parametric oscillator to the study of complexation equilibria in dilute aqueous solutions

The Thermodynamic Overlapping pKa of the Antitumor Drug Ibrutinib Using Multiwavelength UV/VIS-Spectroscopy and Potentiometry

Contact Info

Product

Resources

About

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water

Cation–π induced aggregation of water-soluble [Pt^II(diimine)(Lⁿ-S,O)]⁺complexes studied by¹H DOSY NMR and TEM: from ‘dimer aggregates’ in acetonitrile to nano-aggregates (‘metallogels’) in water