8 research outputs found
Superhydrophobic and Slippery Lubricant-Infused Flexible Transparent Nanocellulose Films by Photoinduced ThiolâEne Functionalization
Films
comprising nanofibrillated cellulose (NFC) are suitable substrates
for flexible devices in analytical, sensor, diagnostic, and display
technologies. However, some major challenges in such developments
include their high moisture sensitivity and the complexity of current
methods available for functionalization and patterning. In this work,
we present a facile process for tailoring the surface wettability
and functionality of NFC films by a fast and versatile approach. First,
the NFC films were coated with a layer of reactive nanoporous silicone
nanofilament by polycondensation of trichlorovinylsilane (TCVS). The
TCVS afforded reactive vinyl groups, thereby enabling simple UV-induced
functionalization of NFC films with various thiol-containing molecules
via the photo âclickâ thiolâene reaction. Modification
with perfluoroalkyl thiols resulted in robust superhydrophobic surfaces,
which could then be further transformed into transparent slippery
lubricant-infused NFC films that displayed repellency against both
aqueous and organic liquids with surface tensions as low as 18 mN·m<sup>â1</sup>. Finally, transparent and flexible NFC films incorporated
hydrophilic micropatterns by modification with OH, NH<sub>2</sub>,
or COOH surface groups, enabling space-resolved superhydrophobicâhydrophilic
domains. Flexibility, transparency, patternability, and perfect superhydrophobicity
of the produced nanocellulose substrates warrants their application
in biosensing, display protection, and biomedical and diagnostics
devices
Video1_1D micro-nanopatterned integrin ligand surfaces for directed cell movement.AVI
Cell-extracellular matrix (ECM) adhesion mediated by integrins is a highly regulated process involved in many vital cellular functions such as motility, proliferation and survival. However, the influence of lateral integrin clustering in the coordination of cell front and rear dynamics during cell migration remains unresolved. For this purpose, we describe a novel protocol to fabricate 1D micro-nanopatterned stripes by integrating the block copolymer micelle nanolithography (BCMNL) technique and maskless near UV lithography-based photopatterning. The photopatterned 10Â ÎŒm-wide stripes consist of a quasi-perfect hexagonal arrangement of gold nanoparticles, decorated with the RGD (arginine-glycine-aspartate) motif for single integrin heterodimer binding, and placed at a distance of 50, 80, and 100Â nm to regulate integrin clustering and focal adhesion dynamics. By employing time-lapse microscopy and immunostaining, we show that the displacement and speed of fibroblasts changes according to the nanoscale spacing of adhesion sites. We found that as the lateral spacing of adhesive peptides increased, fibroblast morphology was more elongated. This was accompanied by a decreased formation of mature focal adhesions and stress fibers, which increased cell displacement and speed. These results provide new insights into the migratory behavior of fibroblasts in 1D environments and our protocol offers a new platform to design and manufacture confined environments in 1D for integrin-mediated cell adhesion.</p
Video4_1D micro-nanopatterned integrin ligand surfaces for directed cell movement.AVI
Cell-extracellular matrix (ECM) adhesion mediated by integrins is a highly regulated process involved in many vital cellular functions such as motility, proliferation and survival. However, the influence of lateral integrin clustering in the coordination of cell front and rear dynamics during cell migration remains unresolved. For this purpose, we describe a novel protocol to fabricate 1D micro-nanopatterned stripes by integrating the block copolymer micelle nanolithography (BCMNL) technique and maskless near UV lithography-based photopatterning. The photopatterned 10Â ÎŒm-wide stripes consist of a quasi-perfect hexagonal arrangement of gold nanoparticles, decorated with the RGD (arginine-glycine-aspartate) motif for single integrin heterodimer binding, and placed at a distance of 50, 80, and 100Â nm to regulate integrin clustering and focal adhesion dynamics. By employing time-lapse microscopy and immunostaining, we show that the displacement and speed of fibroblasts changes according to the nanoscale spacing of adhesion sites. We found that as the lateral spacing of adhesive peptides increased, fibroblast morphology was more elongated. This was accompanied by a decreased formation of mature focal adhesions and stress fibers, which increased cell displacement and speed. These results provide new insights into the migratory behavior of fibroblasts in 1D environments and our protocol offers a new platform to design and manufacture confined environments in 1D for integrin-mediated cell adhesion.</p
Video3_1D micro-nanopatterned integrin ligand surfaces for directed cell movement.AVI
Cell-extracellular matrix (ECM) adhesion mediated by integrins is a highly regulated process involved in many vital cellular functions such as motility, proliferation and survival. However, the influence of lateral integrin clustering in the coordination of cell front and rear dynamics during cell migration remains unresolved. For this purpose, we describe a novel protocol to fabricate 1D micro-nanopatterned stripes by integrating the block copolymer micelle nanolithography (BCMNL) technique and maskless near UV lithography-based photopatterning. The photopatterned 10Â ÎŒm-wide stripes consist of a quasi-perfect hexagonal arrangement of gold nanoparticles, decorated with the RGD (arginine-glycine-aspartate) motif for single integrin heterodimer binding, and placed at a distance of 50, 80, and 100Â nm to regulate integrin clustering and focal adhesion dynamics. By employing time-lapse microscopy and immunostaining, we show that the displacement and speed of fibroblasts changes according to the nanoscale spacing of adhesion sites. We found that as the lateral spacing of adhesive peptides increased, fibroblast morphology was more elongated. This was accompanied by a decreased formation of mature focal adhesions and stress fibers, which increased cell displacement and speed. These results provide new insights into the migratory behavior of fibroblasts in 1D environments and our protocol offers a new platform to design and manufacture confined environments in 1D for integrin-mediated cell adhesion.</p
Video5_1D micro-nanopatterned integrin ligand surfaces for directed cell movement.AVI
Cell-extracellular matrix (ECM) adhesion mediated by integrins is a highly regulated process involved in many vital cellular functions such as motility, proliferation and survival. However, the influence of lateral integrin clustering in the coordination of cell front and rear dynamics during cell migration remains unresolved. For this purpose, we describe a novel protocol to fabricate 1D micro-nanopatterned stripes by integrating the block copolymer micelle nanolithography (BCMNL) technique and maskless near UV lithography-based photopatterning. The photopatterned 10Â ÎŒm-wide stripes consist of a quasi-perfect hexagonal arrangement of gold nanoparticles, decorated with the RGD (arginine-glycine-aspartate) motif for single integrin heterodimer binding, and placed at a distance of 50, 80, and 100Â nm to regulate integrin clustering and focal adhesion dynamics. By employing time-lapse microscopy and immunostaining, we show that the displacement and speed of fibroblasts changes according to the nanoscale spacing of adhesion sites. We found that as the lateral spacing of adhesive peptides increased, fibroblast morphology was more elongated. This was accompanied by a decreased formation of mature focal adhesions and stress fibers, which increased cell displacement and speed. These results provide new insights into the migratory behavior of fibroblasts in 1D environments and our protocol offers a new platform to design and manufacture confined environments in 1D for integrin-mediated cell adhesion.</p
Video2_1D micro-nanopatterned integrin ligand surfaces for directed cell movement.AVI
Cell-extracellular matrix (ECM) adhesion mediated by integrins is a highly regulated process involved in many vital cellular functions such as motility, proliferation and survival. However, the influence of lateral integrin clustering in the coordination of cell front and rear dynamics during cell migration remains unresolved. For this purpose, we describe a novel protocol to fabricate 1D micro-nanopatterned stripes by integrating the block copolymer micelle nanolithography (BCMNL) technique and maskless near UV lithography-based photopatterning. The photopatterned 10Â ÎŒm-wide stripes consist of a quasi-perfect hexagonal arrangement of gold nanoparticles, decorated with the RGD (arginine-glycine-aspartate) motif for single integrin heterodimer binding, and placed at a distance of 50, 80, and 100Â nm to regulate integrin clustering and focal adhesion dynamics. By employing time-lapse microscopy and immunostaining, we show that the displacement and speed of fibroblasts changes according to the nanoscale spacing of adhesion sites. We found that as the lateral spacing of adhesive peptides increased, fibroblast morphology was more elongated. This was accompanied by a decreased formation of mature focal adhesions and stress fibers, which increased cell displacement and speed. These results provide new insights into the migratory behavior of fibroblasts in 1D environments and our protocol offers a new platform to design and manufacture confined environments in 1D for integrin-mediated cell adhesion.</p
High-Density Droplet Microarray of Individually Addressable Electrochemical Cells
Microarray technology
has shown great potential for various types
of high-throughput screening applications. The main read-out methods
of most microarray platforms, however, are based on optical techniques,
limiting the scope of potential applications of such powerful screening
technology. Electrochemical methods possess numerous complementary
advantages over optical detection methods, including its label-free
nature, capability of quantitative monitoring of various reporter
molecules, and the ability to not only detect but also address compositions
of individual compartments. However, application of electrochemical
methods for the purpose of high-throughput screening remains very
limited. In this work, we develop a high-density individually addressable
electrochemical droplet microarray (eDMA). The eDMA allows for the
detection of redox-active reporter molecules irrespective of their
electrochemical reversibility in individual nanoliter-sized droplets.
Orthogonal band microelectrodes are arranged to form at their intersections
an array of three-electrode systems for precise control of the applied
potential, which enables direct read-out of the current related to
analyte detection. The band microelectrode array is covered with a
layer of permeable porous polymethacrylate functionalized with a highly
hydrophobicâhydrophilic pattern, forming spatially separated
nanoliter-sized droplets on top of each electrochemical cell. Electrochemical
characterization of single droplets demonstrates that the underlying
electrode system is accessible to redox-active molecules through the
hydrophilic polymeric pattern and that the nonwettable hydrophobic
boundaries can spatially separate neighboring cells effectively. The
eDMA technology opens the possibility to combine the high-throughput
biochemical or living cell screenings using the droplet microarray
platform with the sequential electrochemical read-out of individual
droplets
Reactive Superhydrophobic Surface and Its Photoinduced Disulfide-ene and Thiol-ene (Bio)functionalization
Reactive
superhydrophobic surfaces are highly promising for biotechnological,
analytical, sensor, or diagnostic applications but are difficult to
realize due to their chemical inertness. In this communication, we
report on a photoactive, inscribable, nonwettable, and transparent
surface (PAINTS), prepared by polycondensation of trichlorovinylsilane
to form thin transparent reactive porous nanofilament on a solid substrate.
The PAINTS shows superhydrophobicity and can be conveniently functionalized
with the photoclick thiol-ene reaction. In addition, we show for the
first time that the PAINTS bearing vinyl groups can be easily modified
with disulfides under UV irradiation. The effect of superhydrophobicity
of PAINTS on the formation of high-resolution surface patterns has
been investigated. The developed reactive superhydrophobic coating
can find applications for surface biofunctionalization using abundant
thiol or disulfide bearing biomolecules, such as peptides, proteins,
or antibodies