Supported Bilayer Lipid Membrane Arrays on Photopatterned Self‐Assembled Monolayers

Abstract

This work demonstrates the use of photocleavable cholesterol derivatives to create supported bilayer lipid membrane arrays on silica. The photocleavable cholesteryl tether is attached to the surface by using the reaction of an amine-functionalized self-assembled monolayer (SAM) and the N-hydroxysuccinimide-based reagent 9. The resultant SAM contains an ortho-nitrobenzyl residue that can be cleaved by photolysis by using soft (365 nm) UV light regenerating the original amine surface, and which can be patterned using a mask. The photoreaction yield was approximately 75 % which was significantly higher than previously found for related ortho-nitrobenzyl photochemistry on gold substrates. The SAMs were characterized by means of contact angle measurements, ellipsometry and X-ray photoelectron spectroscopy. Patterned surfaces were characterized with SEM and AFM. After immersing the patterned surface into a solution containing small unilamellar vesicles of egg phosphatidylcholine (PC), supported lipid membranes were formed comprised of lipid bilayer over the amine functionalized "hydrophilic" regions and lipid monolayer over the cholesteryl "hydrophobic" regions. This was confirmed by fluorescence microscopy and AFM. FRAP studies yielded a lateral diffusion coefficient for the probe molecule of 0.14+/-0.05 microm(2) s(-1) in the bilayer regions and approximately 0.01 microm(2) s(-1) in the monolayer regions. This order of magnitude difference in diffusion coefficients effectively serves to isolate the bilayer regions from one another, thus creating a bilayer array.

Triplex DNA Nanostructures: From Basic Properties to Applications

“…[26a, 101] Within these efforts, external triggers such as heat, [102] light, [103] pH, [104] electrical or magnetic signals, [105] chemical stimuli, [23a, 106] enzymes,a nd DNAzymes [26d, 107] have been used to switch the physical or chemical properties of the materials.The triggers may induce reversible switching functions or ON-OFF signal switching cycles.Numerous applications of stimuli-responsive materials have been suggested, including the controlled release of drugs, [108] sensors, [109] surface patterning, [110] robotics and actuators, [111] and information-storage and -processing systems. [26a, 101] Within these efforts, external triggers such as heat, [102] light, [103] pH, [104] electrical or magnetic signals, [105] chemical stimuli, [23a, 106] enzymes,a nd DNAzymes [26d, 107] have been used to switch the physical or chemical properties of the materials.The triggers may induce reversible switching functions or ON-OFF signal switching cycles.Numerous applications of stimuli-responsive materials have been suggested, including the controlled release of drugs, [108] sensors, [109] surface patterning, [110] robotics and actuators, [111] and information-storage and -processing systems.…”

“…Extensive studies have been directed at the development of stimuli-responsive materials. [26a, 101] Within these efforts, external triggers such as heat, [102] light, [103] pH, [104] electrical or magnetic signals, [105] chemical stimuli, [23a, 106] enzymes,a nd DNAzymes [26d, 107] have been used to switch the physical or chemical properties of the materials.The triggers may induce reversible switching functions or ON-OFF signal switching cycles.Numerous applications of stimuli-responsive materials have been suggested, including the controlled release of drugs, [108] sensors, [109] surface patterning, [110] robotics and actuators, [111] and information-storage and -processing systems. [112] In this Section, the preparation of stimuli-responsive DNA-triplex-functionalized materials will be described, and their potential applications will be addressed.…”

Photoactive SAM surface for control of cell attachment

“…DT-Au 1.07 ± 0.14 BNBA-DT-Au 3.21 ± 0.15 PEG-BNBA-DT-Au 3.86 ± 0.54 WCA measurements were taken at different UV exposure time durations as described in previous studies [46,47]. As shown in Fig.…”

Photosynthetic Proteins in Supported Lipid Bilayers: Towards a Biokleptic Approach for Energy Capture

“…This systems allows the pre‐formation of the SAM on the gold substrate and the subsequent deposition of vesicles on the substrate, resulting in a sufficiently small‐to‐medium sized reservoir (1–2 nm thick) between the bilayer and the gold, to incorporate trans‐membrane proteins . A potential advantage of this thiol‐based SAM approach is the ease with which the SAMs can be patterned using either photolithography or microcontact printing …”