Microfluidic passive permeability assay using nanoliter droplet interface lipid bilayers.

摘要: Membrane permeability assays play an important role in assessing drug transport activities across biological membranes. However, conventional parallel artificial membrane (PAMPA), the model used is dissimilar to membranes physically and chemically. Here, we describe a microfluidic passive assay using droplet interface bilayers (DIBs). In network, nanoliter-sized donor acceptor aqueous droplets are alternately formed cross-flowing oil containing phospholipids. Subsequently, selective removal of through hydrophobic pseudo-porous sidewalls induces contact lipid monolayers, creating arrayed planar DIBs between droplets. Permeation fluorescein from was fluorometrically measured. From measured data simple diffusion calculated effective permeabilities 5.1 × 10−6 cm s−1, 60.0 87.6 s−1 with at pH values 7.5, 6.4 5.4, respectively. The intrinsic specific monoanionic neutral species were obtained similarly. We also permeation caffeine 10 min UV microspectroscopy, obtaining 20.8 s−1. With small solution volumes, short measurement time, ability measure wide range compounds, this device has considerable potential as platform for high-throughput assays.