par Botte, P.;Symons, Marc;Swysen, Christine;Sybesma, Christiaan;Lannoye, Robert 
;Hurwitz, Heinz Dieter
Référence Journal of electroanalytical chemistry and interfacial electrochemistry, 214, 1-2, page (407-425)
Publication Publié, 1986-12
;Hurwitz, Heinz Dieter Référence Journal of electroanalytical chemistry and interfacial electrochemistry, 214, 1-2, page (407-425)
Publication Publié, 1986-12
Article révisé par les pairs
| Résumé : | We have developed a method for investigating the electrochemical parameters at the surface of chromatophore membranes of photosynthetic bacteria using an intrinsic probe constituted from the natural carotenoid pigments. The spectrometric measurement of the electrochromic shift of these pigments is determined as a function of the composition of the external medium. The treatment relies further on the appropriate choice of an ideally specific ionophore used to shunt the membrane electrically and on the introduction of one divalent and one monovalent reference ion which have negligible effects on complexation of the surface sites. The results prove the applicability of the Poisson-Boltzman treatment for surface charge density and surface potential derivation. Deviations from the ideal Gouy-Champman behaviour are interpreted in terms of associations of cations with charged surface sites. Association constants have been derived. © 1986. |
