Dielectric properties of adsorption/ionization site of pentachlorophenol in lipid membranes

Chemical Speciation of Organics and of Metals at Biological Interphases

“…Other measurements averaged to e of 30 to 33 at the interface between polar head groups and the hydrocarbon core [176]. The e of the absorption site of pentachlorophenoxide, the deprotonated species of PCP, is approximately 8.4 for PC membranes and 18 for the negatively charged PG membranes [177]. This means that pentachlorophenoxide is more deeply intercalated into the membrane than other ionogenic compounds, probably due to the very bulky and hydrophobic chloro substituents.…”

Defects in ordered aggregates of cardiolipin visualized by atomic force microscopy

“…In general, chemicals which partition inside the hydrophobic region of the membrane will favour the inverted hexagonal phase because they can fill the hydrocarbon region of the phase. In this work attention has been focused on the effects of pentachlorophenol (PCP) and dinitrophenol (DNP) which are known to alter some physico-chemical characteristics of natural and artificial membranes (Bielawski et al, 1966;Mitchell and Moyle, 1967;Croghan et al, 1969;Smejtek et al, 1976Smejtek et al, , 1987Duxbury and Thompson, 1987).…”

“…It is known since many years that DNP decreases electrical resistance of synthetic bilayers separating two aqueous compartments (Bielawski et al, 1966); the increase of the electrical conductance was found to be dependent on both the lipid composition and the charge of bilayers (Hopfer et al, 1970;McLaughlin, 1972). Similar effects on the electrical conductivity are caused in lipid bilayers by pentachlorophenol (Smejtek et al, 1976(Smejtek et al, , 1987Duxbury and Thompson, 1987;Suwalsky et al, 1990). Of great relevance are also the effects of DNP and PCP on the properties of energy-transducing membranes.…”

Partitioning of Tetrachlorophenol into Lipid Bilayers and Sarcoplasmic Reticulum: Effect of Length of Acyl Chains, Carbonyl Group of Lipids and Biomembrane Structure

“…6). The UV spectral shifts of membranebound ionized pentachlorophenol were due to hydrogen bonding of (A-) to water penetrating into the membrane interface (Smejtek, et al 1987). It should be mentioned that no such shifts were detected for un-ionized pentachlorophenol.…”

“…Effect of dipolar layer on partition. Least-squares-fit values of the infinite dilution partition coefficient, Kp x0 , of the un-ionized (HA) and ionized (A-) species of TeCP assumed that un-ionized TeCP is present in the membrane below the water penetration layer since solvatochromic shifts of un-ionized pentachlorophenol were not observed (Smejtek, Barstad & Wang, 1987). It is very likely that the hydroxyl group of TeCP forms hydrogen bonds with oxygens of phosphate groups of DOPC and DODPC rather than with water.…”