Freestanding lipid bilayers are one of the most used model systems to mimic biological cell membranes. To form an unsupported bilayer, we employ two aqueous fingers in a microfluidic chip surrounded by an oily phase that contains lipids. Upon pushing two aqueous fingers forward, their interface becomes decorated with a lipid monolayer and eventually zip to form a bilayer when the monolayers have nanoscopic contact with each other. Using this straightforward approach, the quick and easy bilayer formation is facilitated by oil draining into the microfluidic device material consisting of polydimethylsiloxane. However, the oil drainage limits the lifetime of a bilayer to about 1 h. We demonstrate that this drainage can be managed, resulting in superior bilayer stability and an increased lifetime of several hours when using a pressure-controlled system. Applying different pressures to the aqueous fingers in the microfluidic chip, the formed bilayer can even be bent to a desired curvature. Extracting the contact angle and the resulting curvature of the bilayer region, for a given applied pressure difference, both the bilayer tension and the surface tension of each lipid monolayer can be derived from a single experiment using the Young Laplace pressure equation.

1.
T.
Osaki
and
S.
Takeuchi
, “
Artificial cell membrane systems for biosensing applications
,”
Anal. Chem.
89
(
1
),
216
231
(
2016
).
2.
L.
Liu
,
C.
Yang
,
K.
Zhao
et al., “
Ultrashort single-walled carbon nanotubes in a lipid bilayer as a new nanopore sensor
,”
Nat. Commun.
4
,
2989
(
2013
).
3.
G. F.
Schneider
and
C.
Dekker
, “
DNA sequencing with nanopores
,”
Nat. Biotech.
30
,
326
328
(
2012
).
4.
C. E.
Ashley
,
E. C.
Carnes
,
G. K.
Philips
,
D.
Padilla
,
P. N.
Durfee
,
P. A.
Brown
,
T. N.
Hanna
,
J.
Liu
,
B.
Philips
,
M. B.
Carter
,
N. J.
Carroll
,
X.
Jiang
,
D. R.
Dunphy
,
Ch. L.
Willman
,
D. N.
Petsev
,
D. G.
Evans
,
A. N.
Parikh
,
B.
Chackerian
,
W.
Wharton
,
D. S.
Peabody
, and
C. J.
Brinker
, “
The targeted delivery of multicomponent cargos to cancer cells by nanoporous particle-supported lipid bilayers
,”
Nat. Mater.
10
,
389
397
(
2011
).
5.
T.
Lian
and
R. H.
Ho
, “
Trends and developments in liposome drug delivery systems
,”
Pharm. Sci.
90
(
6
),
667
680
(
2001
).
6.
A.
Sumino
,
T.
Dewa
,
M.
Kondo
,
T.
Morii
,
H.
Hashimoto
,
A. T.
Gardiner
,
R. J.
Cogdell
, and
M.
Nango
, “
Selective assembly of photosynthetic antenna proteins into a domain-structured lipid bilayer for the construction of artificial photosynthetic antenna systems: Structural analysis of the assembly using surface plasmon resonance and atomic force microscopy active transport of Ca2+ by an artificial photosynthetic membrane
,”
Langmuir
27
(
3
),
1092
1101
(
2011
).
7.
I. M.
Bennett
,
H. M. V.
Farfano
,
F.
Bogani
,
A.
Primak
,
P. A.
Liddell
,
L.
Otero
,
L.
Sereno
,
J. J.
Silber
,
A. L.
Moore
,
Th. A.
Moore
, and
D.
Gust
, “
Active transport of Ca2+ by an artificial photosynthetic membrane
,”
Nature
420
,
398
401
(
2002
).
8.
A. D.
Miller
, “
Cationic liposomes for gene therapy
,”
Angew. Chem. Int. Ed.
37
,
1768
1785
(
1998
).
9.
E. T.
Castellana
and
P. S.
Cremer
, “
Solid supported lipid bilayers: From biophysical studies to sensor design
,”
Surf. Sci.
61
(
10
),
429
444
(
2006
).
10.
P. S.
Cremer
and
S. G.
Boxer
, “
Formation and spreading of lipid bilayers on planar glass supports
,”
J. Phys. Chem. B
103
,
2554
2559
(
1999
).
11.
T.
Ide
and
T.
Ichikawa
, “
A novel method for artificial lipid bilayer formation
,”
Biosens. Bioelectron.
21
(
4
),
672
677
(
2005
).
12.
R. S.
Ries
,
H.
Choi
,
R.
Blunck
,
F.
Bezanilla
, and
J. R.
Health
, “
Black lipid membranes: Visualizing the structure, dynamics, and substrate dependence of membranes
,”
J. Phys. Chem. B
108
,
16040
16049
(
2004
).
13.
R.
Zeineldin
,
J. A.
Last
,
A. L.
Slade
,
L. K.
Ista
,
P.
Bisong
,
M. J.
O’Brien
,
S. R. J.
Brueck
,
D. Y.
Sasaki
, and
G. P.
Lopez
, “
Using bicellar mixtures to form supported and suspended lipid bilayers on silicon chips
,”
Langmuir
22
,
8163
8168
(
2006
).
14.
M.
Bally
,
K.
Bailey
,
K.
Sugihara
,
D.
Grieshaber
,
J.
Voeroes
, and
B.
Staedler
, “
Liposome and lipid bilayer arrays towards biosensing applications
,”
Small
6
(
22
),
2481
2497
(
2010
).
15.
X.
Li
,
K. G.
Klemic
,
M. A.
Reed
, and
F. J.
Sigworth
, “
Microfluidic system for planar patch clamp electrode arrays
,”
Nano Lett.
6
(
4
),
815
819
(
2006
).
16.
K.
Kamiya
,
T.
Osaki
,
K.
Nakao
,
R.
Kawano
,
S.
Fujii
,
N.
Misawa
,
M.
Hayakawa
, and
S.
Takeuchi
, “
Electrophysiological measurement of ion channels on plasma/organelle membranes using an on-chip lipid bilayer system
,”
Nature
8
,
17498
(
2018
).
17.
M. S.
Khan
,
N. S.
Dosoky
, and
J. D.
Williams
, “
Engineering lipid bilayer membranes for protein studies
,”
Mol. Sci.
14
(
11
),
21561
21597
(
2013
).
18.
C. E.
Stanley
,
K. S.
Elvira
,
X. Z.
Niu
,
A. D.
Gee
,
O.
Ces
,
J. B.
Edel
, and
A. J.
deMello
, “
A microfluidic approach for high-throughput droplet interface bilayer (DIB) formation
,”
Chem. Commun.
46
(
10
),
1565
1776
(
2010
).
19.
H.
Bayley
,
B.
Cronin
,
A.
Heron
,
M. A.
Holden
,
W.
Hwang
,
R.
Syeda
,
J.
Thompson
, and
M.
Wallace
, “
Droplet interface bilayers
,”
Mol. Biosyst.
4
(
12
),
1191
1208
(
2008
).
20.
M. A.
Nguyen
,
B.
Srijanto
,
C. P.
Collier
,
S. T.
Retterer
, and
S. A.
Sarles
, “
Hydrodynamic trapping for rapid assembly and in situ electrical characterization of droplet interface bilayer arrays
,”
Lab Chip
16
(
18
),
3576
3588
(
2016
).
21.
N. E.
Barlow
,
G.
Bolognesi
,
S.
Haylock
,
A. J.
Flemming
,
N. J.
Brooks
,
L. M. C.
Barter
, and
O.
Ces
, “
Rheological droplet interface bilayers (rheo-DIBs): Probing the unstirred water layer effect on membrane permeability via spinning disk induced shear stress
,”
Nature
7
,
17551
(
2017
).
22.
J. R.
Thompson
,
A. J.
Heron
,
Y.
Santoso
, and
M. I.
Wallace
, “
Enhanced stability and fluidity in droplet on hydrogel bilayers for measuring membrane protein diffusion
,”
Am. Chem. Soc.
7
(
12
),
3875
3878
(
2007
).
23.
J. B.
Fleury
,
O.
Claussen
,
S.
Herminghaus
,
M.
Brinkmann
, and
R.
Seemann
, “
Mechanical stability of ordered droplet packings in microfluidic channel
,”
Appl. Phys. Lett.
99
,
244104
(
2011
).
24.
U. D.
Schiller
,
J. B.
Fleury
,
R.
Seemann
, and
G.
Gompper
, “
Collective waves in dense and confined microfluidic droplet arrays
,”
Soft Matter
11
,
5850
5861
(
2015
).
25.
N.
Malmstadt
,
M. A.
Nash
,
R. F.
Purnell
, and
J. J.
Schmidt
, “
Automated formation of lipid-bilayer membranes in a microfluidic device
,”
Nano Lett.
6
(
9
),
1961
1965
(
2006
).
26.
J. N.
Vargas
,
R.
Seemann
, and
J. B.
Fleury
, “
Fast membrane hemifusion via dewetting between lipid bilayers
,”
Soft Matter
10
,
9293
9299
(
2014
).
27.
S.
Thutupalli
,
J. B.
Fleury
,
A.
Steinberger
,
S.
Herminghaus
, and
R.
Seemann
, “
Why can artificial membranes be fabricated so rapidly in microfluidics
,”
Chem. Commun.
49
,
1443
1445
(
2013
).
28.
P.
Heo
,
S.
Ramakrishnan
,
J.
Coleman
,
J. E.
Rothman
,
J. B.
Fleury
, and
F.
Pincet
, “
Highly reproducible physiological asymmetric membrane with freely diffusing embedded proteins in a 3D-printed microfluidic setup
,”
Small
10
,
1900725
(
2019
).
29.
S.
Kalsi
,
A. M.
Powl
,
B. A.
Wallace
,
H.
Morgen
, and
M. R. R.
de Planque
, “
Shaped apertures in photoresist films enhance the lifetime and mechanical stability of suspended lipid bilayers
,”
Biophys. J.
106
(
8
),
1650
1659
(
2014
).
30.
A.
Hirano-Iwata
,
A.
Oshima
,
H.
Mozumi
,
Y.
Kimura
, and
M.
Niwano
, “
Stable lipid bilayers based on micro- and nano-fabrication
,”
Anal. Sci.
28
(
11
),
1049
1057
(
2012
).
31.
D. B.
Weibel
,
W. R.
DiLuzo
, and
G. M.
Whitesides
, “
Microfabrication meets microbiology
,”
Nat. Rev. Microbiol.
5
(
3
),
208
218
(
2007
).
32.
G. J.
Taylor
,
G. A.
Venkatesan
,
C. P.
Collier
, and
S. A.
Sarles
, “
Direct in situ measurement of specific capacitance, monolayer tension, and bilayer tension in a droplet interface bilayer
,”
Soft Matter
11
,
7592
7605
(
2015
).
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