title: High yield, reproducible and quasi-automated bilayer formation in a microfluidic format.
abstract: A microfluidic platform is reported for various experimentation schemes on cell membrane models and membrane proteins using a combination of electrical and optical measurements, including confocal microscopy. Bilayer lipid membranes (BLMs) are prepared in the device upon spontaneous and instantaneous thinning of the lipid solution in a 100-μm dry-etched aperture in a 12.5-μm thick Teflon foil. Using this quasi-automated approach, a remarkable 100% membrane formation yield is reached (including reflushing in 4% of the cases), and BLMs are stable for up to 36 h. Furthermore, the potential of this platform is demonstrated for (i) the in-depth characterization of BLMs comprising both synthetic and natural lipids (1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) and L-α-phosphatidylcholine (L-α-PC)/cholesterol, respectively) in terms of seal resistance, capacitance, surface area, specific capacitance, and membrane hydrophobic thickness; (ii) confocal microscopy imaging of phase separation in sphingomyelin/L-α-PC/cholesterol ternary membranes; (iii) electrical measurements of individual nanopores (α-hemolysin, gramicidin); and (iv) indirect assessment of the alteration of membrane properties upon exposure to chemical stimuli using the natural nanopore gramicidin as a sensor.
authors.affiliation: BIOS-Lab on a Chip Group, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands.
authors.forename: Verena C
authors.initials: VC
authors.lastname: Stimberg
authors.forename: Johan G
authors.initials: JG
authors.lastname: Bomer
authors.forename: Iris
authors.initials: I
authors.lastname: van Uitert
authors.forename: Albert
authors.initials: A
authors.lastname: van den Berg
authors.forename: Séverine
authors.initials: S
authors.lastname: Le Gac
mesh_terms: D002784:Cholesterol / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008567:Membranes, Artificial; D044085:Microfluidics / Q000379:methods*; D018613:Microscopy, Confocal; D010713:Phosphatidylcholines / Q000737:chemistry
chemical_list: D008051:Lipid Bilayers; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; C021016:1,2-diphytanoylphosphatidylcholine; D002784:Cholesterol