Billing, CarenCukrowski, IgnacyJordan, Blake2014-05-222014-09-302013-09Billing, C, Cukrowski, I & Jordan, B 2013, 'A novel approach to monitoring of the diffusion junction potential in speciation studies by polarography under very acidic conditions : Part I : The reversible cd(ii)-picolinic acid system', Electroanalysis, vol. 25, no. 9, pp. 2221-2230.1040-0397 (print)1521-4109 (online)10.1002/elan.201300256http://hdl.handle.net/2263/39877A new polarographic procedure has been developed for the study of metal-ligand equilibria at pH<2 by applying an in situ monitoring of the diffusion junction potential by introducing a noncomplexing witness metal ion, Tl(I). As a case study, this procedure was applied to the Cd(II)-picolinic acid (pyridine-2-carboxylic acid) system; DCTAST polarography was employed at 25 8C and ionic strength of 0.25–0.5 M (H,Na)NO3. Log b values of 4.26 0.03, 7.86 0.11 and 10.47 0.12 were obtained for the ML, ML2 and ML3 complexes, respectively, and compare well to literature values. The first log b (6.27 0.07) value for the MLH species was successfully determined, for which a crystal structure has been reported recently.en© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is the pre-peer reviewed version of the following article : A novel approach to monitoring of the diffusion junction potential in speciation studies by polarography under very acidic conditions : Part I : The reversible cd(ii)-picolinic acid system in Electroanalysis, vol. 25, no. 9, pp. 2221-2230, 2013. doi : 10.1002/elan.201300256 which has been published in final form at : http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-4109CadmiumDiffusion junction potentialFormation constantsPicolinic acidVoltammetryPreprint Article