Chronoamperometry at micropipet electrodes for determination of diffusion coefficients and transferred charges at liquid/liquid interfaces

Analytical Chemistry
Yi YuanShigeru Amemiya

Abstract

Chronoamperometry was carried out at liquid/liquid interfaces supported at the tip of micropipet electrodes for direct determination of the diffusion coefficient of a species in the outer solution. The diffusion coefficient was used for subsequent determination of the transferred charges per species from the diffusion-limited steady-state current. A large tip resistance of the micropipets causes prolonged charging current so that the faradic current can be measured accurately only at a long-time regime (typically t > 5 ms). At the same time, the long-time current response at the interfaces surrounded by a thin glass wall of the pipets is enhanced by diffusion of the species from behind the pipet tip. Therefore, numerical simulations of the long-time chronoamperometric response were carried out using the finite element method for accurate determination of diffusion coefficients. Validity of the simulation results was confirmed by studying simple transfer of tetraethylammonium ion. The technique was applied for transfer/adsorption reactions of the natural polypeptide protamine and also for Ca2+ and Mg2+ transfers facilitated by ionophore ETH 129. With the diffusion coefficient of protamine determined to be (1.2 +/- 0.1) x 10(-6) ...Continue Reading

References

Feb 12, 1998·Gene Therapy·F L SorgiL Huang
Feb 24, 2001·Analytical Chemistry·Q QianH H Girault
May 30, 2002·Analytical Chemistry·Cynthia G Zoski, Michael V Mirkin
Sep 25, 2003·Journal of the American Chemical Society·Shigeru AmemiyaTracy L Wazenegger

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Citations

Aug 6, 2010·Analytical and Bioanalytical Chemistry·Shigeru AmemiyaBenjamin Kabagambe
Dec 29, 2005·Analytical Sciences : the International Journal of the Japan Society for Analytical Chemistry·Hajime KatanoToshihide Tsukatani
May 16, 2008·Journal of the American Chemical Society·Patrick J RodgersShigeru Amemiya
Sep 15, 2009·Langmuir : the ACS Journal of Surfaces and Colloids·Ping JingShigeru Amemiya
Sep 3, 2011·Journal of the American Chemical Society·Ryoichi IshimatsuShigeru Amemiya
Feb 7, 2007·Langmuir : the ACS Journal of Surfaces and Colloids·S SenthilkumarR Saraswathi

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