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Title: Dipolar Janus liposomes: formation, electrokinetic motion and self-assembly
Presented herein is the first report on dipolar Janus liposomes–liposomes that contain opposite surface charges decorating the two hemispheres of the same colloidal body. Such heterogeneous organization of surface charge is achieved through cholesterol-modulated lipid phase separation, which sorts anionic/cationic lipids into coexisting liquid-ordered/liquid-disordered domains. We present optimized experimental conditions to produce these liposomes in high yields, based on the gel-assisted hydration of ternary lipid systems consisting of cholesterol, 1,2-dipalmitoyl- sn-glycero -3-phosphocholine, and 1,2-dioleoyl- sn-glycero -3-phosphocholine. The size/charge distribution and domain configuration of these liposomes are characterized in detail by confocal fluorescence microscopy, nanosphere binding and zeta potential measurements. Using confocal fluorescence microscopy, we also follow the electrokinetic motion as well as the electrostatic self-assembly of these new dipolar Janus particles.  more » « less
Award ID(s):
1808123
PAR ID:
10160103
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Soft Matter
Volume:
16
Issue:
9
ISSN:
1744-683X
Page Range / eLocation ID:
2177 to 2184
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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