A Potentiometric Study on the Complex Formation of the Lead(II)-Glycine System.

Berggren, Jan; Börtin, Olle; Gobom, Sylvia; Rømming, Christian; Sydnes, Leiv K.; Sinnwell, Volker; Khan, Shabnam; Vilkov, L. V.; Rypdal, Kristian

doi:10.3891/acta.chem.scand.42a-0685

Cited by 5 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Haltafall 13 and Letagrop14 programs have been complemented with BASIC programs and faster FORTRAN translations ofthese. 4 They are used for calculating and plotting concentrations and for a nonlinear Ieastsquares evaluation of stability constants, allowing variation of any parameters of interest in the titrations performed.…”

Section: The Program Systemmentioning

confidence: 99%

Titration cell and amalgam electrodes used in automated potentiometric measurements

Berggren

Börtin

Gobom

1988

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

Titration vessels, amalgam electrodes, and other assessments which are used in a computeroperated system for potentiometric titrations are described. The titrator is used to study complex formation in solution by means of high-and low-resistance electrodes and volumetric and coulometric addition oftitrants. The computerized procedure is governed by a flexible program for the control of titration procedures, registration of data, and calculations.

show abstract

Section: The Program Systemmentioning

confidence: 99%

Titration cell and amalgam electrodes used in automated potentiometric measurements

Berggren

Börtin

Gobom

1988

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

show abstract

A comparison of the determination of stability constants of complexes of Pb(II) with amino acids using micro‐pH‐metric titrations and cyclic voltammetry

Pettit

Bernard

et al. 1991

Chin. J. Chem.

View full text Add to dashboard Cite

This paper reports the determination of stability constants for complexes of Pb(II) with Gly, Ala, Asp and Gly‐Gly using both micro‐pH‐metric titrations and the application of convolution‐de‐convolution cyclic voltammetry at 25°C and I = 0.10 mol·dm−3 (KNO3). Stability constants were calculated from pH‐metric data using the SUPERQUAD computer program and cyclic voltammograms were collected, stored and manipulated using the E G and G CONDECON 300 software. A′ considerably larger ligand: metal ratio (e.g. 50:1) was possible using voltammetry. Under these conditions, hydroxy complex formation was minimised and the formation of bis‐complexes optimised. Computer based calculations were carried out on PC‐compatible microcomputers fitted with mathematics coprocessors. Evaluation of results from the two techniques suggests that stability constants for the species [PbL2] are reliable when calculated from voltammetry while those for [PbL] are more reliable when determined by pH‐metric titration.

show abstract

Voltammetry as Virtual Potentiometric Sensor in Modelling of a Metal/Ligand System and Refinement of Stability Constants. Part 5

Cukrowski

Magampa

Mkwizu

2006

Helvetica Chimica Acta

View full text Add to dashboard Cite

The concept of virtual potential (employed here in modelling operations), a unique experimental setup designed and built in our laboratories, and new regression equations derived for nonlinear fitting of quasi‐reversible direct‐current polarograms were combined with the existing rigorous treatment and refinement of polarographic data to establish reliable metal/ligand models and accurate stability constants for the lead(II)/glycine/OH− and lead(II)/sarcosine/OH− systems (sarcosine = N‐methylglycine). In the case of glycine, the complexes [M(HL)], [ML], [ML2], and [ML3] were identified, and their stability constants (as log β) were established to be 10.51 ± 0.06, 4.58 ± 0.02, 7.19 ± 0.10, and 9.27 ± 0.02, respectively, the complex [ML3] being reported here for the first time (Table 2). The system with sarcosine involving [M(HL)], [ML], [ML2], [ML3], and [ML2(OH)2], with the stability constants (as log β) 11.01 ± 0.04, 4.18 ± 0.03, 7.23 ± 0.03, 9.1 ± 0.3, and 15.97 ± 0.07, respectively, is reported for the first time (Table 3). The log K1 value for PbII with sarcosine is a fraction of a log unit smaller when compared with the PbII complex with glycine, in agreement with the literature data for CuII, NiII, and ZnII showing the same trend for these two ligands. The proposed nonlinear curve‐fitting operations expand the applicability of polarography to study reliably and conveniently quasi‐reversible, on the polarographic time scale, metal/ligand systems (systems with involved heterogeneous kinetics).

show abstract

A Potentiometric Study on the Complex Formation of the Lead(II)-Glycine System.

Cited by 5 publications

References 0 publications

Titration cell and amalgam electrodes used in automated potentiometric measurements

Titration cell and amalgam electrodes used in automated potentiometric measurements

A comparison of the determination of stability constants of complexes of Pb(II) with amino acids using micro‐pH‐metric titrations and cyclic voltammetry

Voltammetry as Virtual Potentiometric Sensor in Modelling of a Metal/Ligand System and Refinement of Stability Constants. Part 5

Contact Info

Product

Resources

About