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Merle G, Brunel L, Tingry S, Cretin M, Rolland M, Servat K, Jolivalt C, Innocent C, Seta P. Electrode biomaterials based on immobilized laccase. Application for enzymatic reduction of dioxygen. Materials Science and Engineering: C 2008. [DOI: 10.1016/j.msec.2007.10.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Benhima H, Chiban M, Sinan F, Seta P, Persin M. Removal of lead and cadmium ions from aqueous solution by adsorption onto micro-particles of dry plants. Colloids Surf B Biointerfaces 2008; 61:10-6. [PMID: 17869071 DOI: 10.1016/j.colsurfb.2007.06.024] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Revised: 03/11/2007] [Accepted: 06/25/2007] [Indexed: 11/20/2022]
Abstract
In the present work, Pb(II) and Cd(II) ion adsorption onto inert organic matter (IOM) obtained from ground dried plants: Euphorbia echinus, Launea arborescens, Senecio anthophorbium growing in semi-arid zones of Morocco and Carpobrotus edulis as the Mediterranean plant has been studied. A suspension of plant deroed micro-particles adsorbs lead and cadmium present as ionic species, with a higher affinity for Pb(II). The kinetics and the maximum capacity adsorption depend on the type of plant as well as on the metal ions (atomic weight, ionic radius and electronegativity). The adsorption process is affected by various parameters such as contact time, solution volume to mass of plant particles ratio (m/V), particle size, solution pH and metal concentration. A dose of 25 g/l of adsorbent was optimal to obtain maximum adsorption of both metal ions. The maximum metal uptake was obtained with particles of organic matter of <50 microm. As to classical ionic adsorption phenomena, the adsorption of both metal ions increases with the increase of the initial concentration in the solution. For the two metal cations, the uptake efficiency of the studied plants ranged from: C. edulis>E. echinus>S. anthophorbium>L. arborescens, however, the differences are rather small. Two different waste water types (domestic and industrial) were tested and good results were obtained for removal of Pb(II) and Cd(II) at more than 90%. The removal of the metal and mineral ions waste water was observed for PO(4)(3-) at 88%, for NO(3)(-) at 96.5% and for metal ions (Pb(II), Cd(II), Cu(II) and Zn(II)) at about 100%, using IOM as absorbent.
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Affiliation(s)
- H Benhima
- Laboratoire de Chimie-Physique, Université Ibn Zohr, BP 8106 Cité Dakhla Agadir, Morocco
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Amrate S, Akretche DE, Innocent C, Seta P. Removal of Pb from a calcareous soil during EDTA-enhanced electrokinetic extraction. Sci Total Environ 2005; 349:56-66. [PMID: 16198669 DOI: 10.1016/j.scitotenv.2005.01.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2004] [Revised: 11/06/2004] [Accepted: 01/12/2005] [Indexed: 05/04/2023]
Abstract
Electrokinetic extraction has been tested to remove lead from an Algerian contaminated soil ([Pb] = 4.432 +/- 0.275 mg g(-1)) sited near a battery plant. The effect of EDTA at various concentrations (0.05-0.20 M) on the enhancement of lead transport has been studied by applying a constant voltage corresponding to a nominal electric field strength of 1 V cm(-1) (duration: 240 h). Results of contaminant distribution across the experimental cell have shown efficient transport of lead toward the anode despite the presence of calcite (25%) and the high acid/base buffer capacity of the soil. To avoid ligand loss, which would be anodically oxidized, the cell was modified by adding extra compartments and inserting cation exchange membranes (Neosepta CMX). Thus, simultaneous recovery of EDTA and lead from their chelated solutions has been made possible using the same set-up and by controlling fluids chemistry.
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Affiliation(s)
- S Amrate
- Laboratory of Hydrometallurgy and Molecular Inorganic Chemistry, Faculty of Chemistry, University of Science and Technology Houari Boumediene (USTHB), Bab-Ezzouar, Algiers, Algeria.
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Gherrou A, Kerdjoudj H, Molinari R, Seta P, Drioli E. Fixed sites plasticized cellulose triacetate membranes containing crown ethers for silver(I), copper(II) and gold(III) ions transport. J Memb Sci 2004. [DOI: 10.1016/j.memsci.2003.10.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Rochefeuille S, Jimenez C, Tingry S, Seta P, Desfours J. Mixed Langmuir–Blodgett monolayers containing carboxylic ionophores. Application to Na+ and Ca2+ ISFET-based sensors. Materials Science and Engineering: C 2002. [DOI: 10.1016/s0928-4931(02)00056-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Amounas M, Magne V, Innocent C, Dejean E, Seta P. Elaboration and chemical reactivity of enzyme modified ion exchanging textiles. Enzyme Microb Technol 2002. [DOI: 10.1016/s0141-0229(02)00085-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Canet L, Ilpide M, Seta P. Efficient facilitated transport of lead, cadmium, zinc, and silver across a flat-sheet-supported liquid membrane mediated by lasalocid A. SEP SCI TECHNOL 2002. [DOI: 10.1081/ss-120003047] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Venturini J, Koudoumas E, Couris S, Janot JM, Seta P, Mathis C, Leach S. Optical limiting and nonlinear optical absorption properties of C60–polystyrene star polymer films: C60 concentration dependence. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b201308h] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Marzin C, Tarrago G, Zidane I, Bienvenue E, Seta P, Andrieux C, Gamp H, Saveant JM. New ligand-bridged polyruthenium(II) complexes with cofacial tetrapyrazolic macrocycles. Inorg Chem 2002. [DOI: 10.1021/ic00231a012] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Koudoumas E, Konstantaki M, Mavromanolakis A, Couris S, Ederle Y, Mathis C, Seta P, Leach S. Ultrafast nonlinear optical response of C60–polystyrene star polymers. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00088-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Konstantaki M, Koudoumas E, Couris S, Janot J, Eddaoudi H, Deratani A, Seta P, Leach S. Optical limiting behaviour of the water-soluble C60/γ-cyclodextrin complex. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)00037-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Gumila C, Miquel G, Seta P, Ancelin ML, Delort AM, Jeminet G, Vial HJ. Ionophore-Phospholipid Interactions in Langmuir Films in Relation to Ionophore Selectivity toward Plasmodium-Infected Erythrocytes. J Colloid Interface Sci 1999; 218:377-387. [PMID: 10502369 DOI: 10.1006/jcis.1999.6432] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Carboxylic true ionophores were previously demonstrated to have efficient antimalarial activity against the human parasite Plasmodium falciparum, with a 50% inhibitory concentration around nM and generally high selectivity as compared to their toxic effects against mammalian cell lines. The decreased molecular packing of the erythrocyte membrane outer leaflet after malarial infection could explain the preferential ionophore interaction with infected erythrocytes. Monolayer penetration experiments using different phospholipid films showed strong incorporation of true carboxylic ionophores, from classes 1 (nigericin) and 2 (lasalocid), up to a surface pressure close to film collapse. The interaction was slightly higher with PC (phosphatidylcholine) monolayers than with monolayers composed of cholesterol-containing total lipid extracts from either malaria-infected or normal erythrocytes, and the two latter induced identical interactions with 5-bromo lasalocid. Surface pressure-area isotherms for pure ionophores on water and surface tension of ionophore aqueous solutions clearly highlighted the surface-active characteristics of these ionophores and allowed determination of their molecular area in compact monolayers. The estimated ionophore concentration in the mixed interfacial layers indicates that higher amounts (threefold more) of ionophores might be integrated in infected erythrocyte membrane due to their impaired molecular packing as compared to normal erythrocytes. This infection-enhanced penetration efficiency does not appear directly related to the change in erythrocyte membrane lipid composition, but it could be the basis of ionophore selectivity for infected erythrocytes. Copyright 1999 Academic Press.
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Affiliation(s)
- C Gumila
- Dynamique Moléculaire des Interactions Membranaires, Université Montpellier II, Place Eugène Bataillon, Montpellier Cedex 5, 34095
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Canet L, Vanel P, Aouad N, Tronel-Peyroz E, Palmeri J, Seta P. Impedance and electrical potential across supported liquid membranes: role of interfacial potentials on the active transport of a metal cation. J Memb Sci 1999. [DOI: 10.1016/s0376-7388(99)00160-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Tronel-Peyroz E, Miquel-Mercier G, Vanel P, Seta P. Influence of adsorption on photoinduced electron transfer in supported liquid membranes: the case of C60. Chem Phys Lett 1998. [DOI: 10.1016/s0009-2614(98)00018-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Aouad N, Miquel-Mercier G, Bienvenüe E, Tronel-Peyroz E, Jeminet G, Juillard J, Seta P. Lasalocid (X537A) as a selective carrier for Cd(II) in supported liquid membranes. J Memb Sci 1998. [DOI: 10.1016/s0376-7388(97)00240-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Garaud J, Janot J, Miquel G, Seta P. Photoinduced electron transfer properties of porous polymer membranes doped with the fullerene C60 associated with phospholipids. J Memb Sci 1994. [DOI: 10.1016/0376-7388(94)80087-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Farrera JA, Jaumà A, Ribó JM, Peiré MA, Parellada PP, Roques-Choua S, Bienvenue E, Seta P. The antioxidant role of bile pigments evaluated by chemical tests. Bioorg Med Chem 1994; 2:181-5. [PMID: 7922130 DOI: 10.1016/s0968-0896(00)82013-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Bilirubin, biliverdin and their serum albumin complexes were tested as oxyradical scavengers (superoxide generated by the xanthine/xanthine oxidase system and peroxyl radical-trapping antioxidant ability). As superoxide scavengers the free bile pigments showed activities near to that of serum albumin, higher than the water soluble vitamin E analog Trolox and lower than ascorbic acid. The peroxyl radical-trapping antioxidant abilities of the tested bile pigments were much higher than those of the serum albumin and of the same order as their serum albumin complexes. This interaction with peroxyl radicals showed different stoichiometric factors for bilirubin (approximately 2) and biliverdin (approximately 4).
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Affiliation(s)
- J A Farrera
- Departament de Química Orgànica, Universitat de Barcelona, Catalonia, Spain
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Lamrabte A, Janot JM, Bienvenue E, Momenteau M, Seta P. Photoinitiated vectorial transmembrane electron transfer in bilayers sensitized by a face to face triporphyrin acting as a molecular electronic device. Amplification due to ionic coupling. Photochem Photobiol 1991; 54:123-6. [PMID: 1946689 DOI: 10.1111/j.1751-1097.1991.tb01994.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Under light excitation transmembrane electron transfer is observed when a stacked Zn-Cu-Zn triporphyrin is incorporated in a bilayer between aqueous redox phases. The electric polarization of the membrane due to the photoinduced transmembrane charge flux drives ion transport. This effect increases the net charge transfer across the system, giving rise to an amplification similar to a field effect transistor. Thus this system can be considered an organic phototransistor.
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Affiliation(s)
- A Lamrabte
- Laboratorie de Physicochimie des Systèmes Polyphasés, URA 330 CNRS, Montpellier, France
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Seta P, Bienvenue E, Moore A, Moore T, Gust D. Model systems for photosynthesis acting as photoinduced molecular wires in bilayers. Electrochim Acta 1989. [DOI: 10.1016/0013-4686(89)85055-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Momenteau M, Loock B, Seta P, Bienvenue E, d'Epenoux B. A carotenoporphyrin - quinone triad designed from a basket-handle porphyrin: synthesis and photo electrochemical properties. Tetrahedron 1989. [DOI: 10.1016/s0040-4020(01)85158-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hofmanova A, Bienvenue E, Seta P, Momenteau M. ELECTRON AND PROTON PHOTOTRANSPORTS IN A BILAYER MEMBRANE. ACIDIC PORPHYRIN AND SUPEROXIDE ION AS ΔpH SENSITIVE CHARGE CARRIERS. Photochem Photobiol 1986. [DOI: 10.1111/j.1751-1097.1986.tb03568.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Bienvenue E, Boudou A, Desmazes JP, Gavach C, Georgescauld D, Sandeaux J, Seta P. Transport of mercury compounds across bimolecular lipid membranes: effect of lipid composition, pH and chloride concentration. Chem Biol Interact 1984; 48:91-101. [PMID: 6229346 DOI: 10.1016/0009-2797(84)90009-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The use of bimolecular lipid membranes (BLM) as model membrane allows the analysis of the transport of mercury compounds across the lipidic barriers of biological membranes. The results of flux measurements show that two mercury compounds--HgCl2 and CH3HgCl--cross the BLM but the overall permeabilities are dependent on the pH of the aqueous media, and are not apparently influenced by the different phospholipid constituents of the bilayers. On the other hand, electrical measurements show that, function of the chemical speciation, the transport of this metal is done essentially in the neutral form.
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Helynck G, Luu B, Nussbaum JL, Picken D, Skalidis G, Trifilieff E, Van Dorsselaer A, Seta P, Sandeaux R, Gavach C, Heitz F, Simon D, Spach G. Brain proteolipids. Isolation, purification and effect on ionic permeability of membranes. Eur J Biochem 1983; 133:689-95. [PMID: 6861750 DOI: 10.1111/j.1432-1033.1983.tb07518.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Proteolipid apoproteins have been isolated from a whole bovine brain homogenate by chloroform/methanol extraction, and fractionated by chromatography on modified (lipophilic) Sephadex, followed by ion-exchange chromatography on CM-Trisacryl. The various final, highly hydrophobic, fractions are homogeneous (sodium dodecyl sulfate/polyacrylamide gel electrophoresis). Transmembrane ion transfers were studied by 22Na + flux and electrical conductance measurements. Single channel events were observed at low protein concentrations, in particular with one of the final homogeneous apoproteolipids of molecular mass 24 kDa.
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Seta P, d'Epenoux B, Sandeaux R, Pattus F, Lazdunski C, Gavach C. Voltage and time dependence of the conductance of planar lipid bilayers doped with colicin A. Biochem Biophys Res Commun 1983; 113:765-71. [PMID: 6870888 DOI: 10.1016/0006-291x(83)91065-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Voltage jump studies of planar bilayers doped with colicin A revealed two classes of time and voltage dependent conductance induced by colicin A. The first type of conductance, asymmetrically voltage dependent, measured as a time dependent process, was in agreement with previously described conductances of bilayers doped with colicin A or colicin E1. The second class of conductance appeared as a voltage dependent instantaneous conductance. The significance of this new type of conductance is discussed.
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Seta P, Ormos P, d'Epenoux B, Gavach C. Photocurrent response of bacteriorhodopsin adsorbed on bimolecular lipid membranes. Biochim Biophys Acta 1980; 591:37-52. [PMID: 7388016 DOI: 10.1016/0005-2728(80)90218-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The photo response of bacteriorhodopsin adsorbed on a bimolecular lipid membrane has been investigated using short-circuit current measurements. The results revealed a biphasic current vs. time curve for the photocurrent at pH values of approx. 7. This phenomenon could be modified by altering either the value of the external applied electrical field or the proton concentration differences. The observed effects of the external applied voltage, pH gradient and lipophilic proton carriers enabled us to conclude that the bacteriorhodopsin can be adsorbed in two different states, which give rise to a pumping effect and a flux of protons in opposite directions. A theoretical analysis of the photocycle in relation to the electrical field which acts on the proton uptake and release is proposed. The main effect of this field is to diminish the pumping rate due to the proton motive force resulting from the creation of space-charge in the vicinity of purple membrane fragments.
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Seta P, d'Epenoux B, Gavach C. Electrochemical analysis of transmembrane proton fluexes photogenerated by bacteriorhodopsin in B.L.M. J Electroanal Chem (Lausanne) 1980. [DOI: 10.1016/s0022-0728(80)80277-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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d'Epenoux B, Seta P, Amblard G, Gavach C. The transfer mechanism of tetraalkylammonium ions across a water-nitrobenzene interface and the structure of the double layer. ACTA ACUST UNITED AC 1979. [DOI: 10.1016/s0022-0728(79)80412-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Seta P, Cros D, Sandeaux R, Gavach C. A potentiostatic study of hydrophobic ion transfer across lipid bilayer membranes. ACTA ACUST UNITED AC 1978. [DOI: 10.1016/s0022-0728(78)80118-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Sandeaux R, Seta P, Jeminet G, Alleaume M, Gavach C. The influence of pH on the conductance of lipid bimolecular membranes in relation to the alkaline ion transport induced by carboxylic carriers grisorixin, alborixin and monensin. Biochim Biophys Acta 1978; 511:499-508. [PMID: 28761 DOI: 10.1016/0005-2736(78)90284-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The influence of the pH on the stability and stoichiometry of the complexes formed by carboxylic-antibiotics such as grisorixin, alborixin and monensin with alkaline and alkaline earth cations has been investigated. The maximum values of bimolecular lipid membrane conductance are obtained with grisorixin and potassium ion. The conductance-pH curves show a very pronounced maximum in the neutral pH range. The results are analysed on the basis of a dimeric form of the ionophore in the complex and the possibility of having several charged complexes resulting from an heterogeneous reaction, the number of each complexed form depending on the pH of the bulk solutions.
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