Giant unilamellar vesicles (GUVs) are model membrane systems consisting
of a single lipid bilayer separating an inner lumen from the outer
solution, with dimensions comparable to that of eukaryotic cells. The
importance of these biomimetic systems has recently grown with the
development of easy and safe methods to assemble GUVs from complex
biorelevant compositions. However, size and position control is still a
key challenge for GUV formation and manipulation. We developed a new, gel-assisted
formation method able to produce arrays of giant
unilamellar anchored vesicles (GUAVs) with a predetermined narrow size
distribution. As templates we use micropatterned gel substrates of
cross-linked poly(N-isopropylacrylamide).
(b) with a defined size on the pillars of a micropatterned hydrogel film. A dry layer of lipids spread on the surface of
a dry PNIPAAm gel is hydrated from water coming from below (blue arrows) and swelling the gel. (c) 2D CLSM image
of an array of uniform GUAVs, prepared on a micropatterned PNIPAAm hydrogel. (d) 3D CLSM image of an array of
16 GUAVs zoomed in to a single pillar with one GUAV on top.
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Controlling the vesicle size. GUAVs prepared by PNIPAAm gel-assisted swelling for three different mask/pattern sizes.
(a) CLSM images (xy plane) of GUAVs, labeled with Atto488. (b) CLSM images (xz plane) of GUAVs. (c) Size distribution
of the GUAV diameters. The histograms were obtained by measuring the diameters of roughly 90 GUAVs for each pattern.
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