A fluorescence method for determining transport of charged compounds across lipid bilayer

Abstract

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In Situ Artificial Membrane Permeation Assay under Hydrodynamic Control: Permeability-pH Profiles of Warfarin and Verapamil

“…This group also used the PAMPA method for the high-throughput measurement of octanol/water partition coefficients (19). More membrane models, such as lipid-oil-lipid tri-layer membranes (20), liposome-based membranes (21)(22)(23), bloodbrain barrier mimics (24) and other approaches to permeability measurement (25,26), or prediction of passive intestinal absorption (27) have been reported in the last decade. Also, the effect of lipid composition on permeability was investigated, based on a liposome permeation study (28).…”

Application of Liposome Based Sensors in High-Throughput Screening Systems

“…In contrast to the method proposed by Melchior, the fluorescent assay designed by Przybylo [139] provides information on the transport of charged compounds through the lipid bilayer as well as the penetration of the molecule inside the lipid bilayer. Even though the method is based on a similar design of the liposensor, special requirements regarding probe concentration and localization (for details see [139]) ensure that the measured kinetics represent not only the entrance but also the transport of charged compounds across a lipid membrane.…”

“…Even though the method is based on a similar design of the liposensor, special requirements regarding probe concentration and localization (for details see [139]) ensure that the measured kinetics represent not only the entrance but also the transport of charged compounds across a lipid membrane. Instead of detecting the compound concentration directly, these authors employed an approach in which, instead of the membrane interior, the membrane interfaces were labeled.…”

Modular Chemosensors from Self‐Assembled Vesicle Membranes with Amphiphilic Binding Sites and Reporter Dyes

“…The widely used carboxyfluorescein (CF) dye was selected owing to its sensitivity to local electrostatic potential [10] and easy derivatization with alkyl amines. The sensitivity of coumarin derivative 5 to changes in the local environment had been observed in an earlier study.…”