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Full-Text Articles in Engineering
Enhanced Transmission Of Higher Order Plasmon Modes With Random Au Nanoparticles In Periodic Hole Arrays, Fang-Tzu Chuang
Enhanced Transmission Of Higher Order Plasmon Modes With Random Au Nanoparticles In Periodic Hole Arrays, Fang-Tzu Chuang
Fang-Tzu Chuang
The enhanced transmission of higher order plasmon modes with random gold nanoparticles embedded in periodic hole arrays using asymmetric pair aperture as a unit is investigated in the midinfrared regime. Different thicknesses of gold film were deposited inside holes and then annealed to form randomly sized and distributed nanoparticles. The holes deposited with thin gold film exhibit significantly enhanced transmission in higher order modes after thermal annealing. The enormous local electric field around the nanoparticles enhances the scattering effect that contributes to the enhanced infrared transmission. This unique design, which integrates localized and propagating surface plasmons, provides an easy way …
Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu
Microfabricated Nanotopological Surfaces For Study Of Adhesion-Dependent Cell Mechanosensitivity, Weiqiang Chen, Yubing Sun, Jianping Fu
Weiqiang Chen
Cells exhibit high sensitivity and diverse responses to the intrinsic nanotopography of the extracellular matrix through their nanoscale cellular sensing machinery. A simple microfabrication method for precise control and spatial patterning of the local nanoroughness on glass surfaces by using photolithography and reactive ion etching is reported. It is demonstrated that local nanoroughness as a biophysical cue could regulate a diverse array of NIH/3T3 fi broblast behaviors, including cell morphology, adhesion, proliferation, migration, and cytoskeleton contractility. The capability to control and further predict cellular responses to nanoroughness might suggest novel methods for developing biomaterials mimicking nanotopographic structures in vivo for …
Surface-Micromachined Microfiltration Membranes For Efficient Isolation And Functional Immunophenotyping Of Subpopulations Of Immune Cells, Weiqiang Chen, Nien-Tsu Huang, Boram Oh, Raymond H. W. Lam, Rong Fan, Timothy T. Cornell, Thomas P. Shanley, Katsuo Kurabayashi, Jianping Fu
Surface-Micromachined Microfiltration Membranes For Efficient Isolation And Functional Immunophenotyping Of Subpopulations Of Immune Cells, Weiqiang Chen, Nien-Tsu Huang, Boram Oh, Raymond H. W. Lam, Rong Fan, Timothy T. Cornell, Thomas P. Shanley, Katsuo Kurabayashi, Jianping Fu
Weiqiang Chen
An accurate measurement of the immune status in patients with immune system disorders is critical in evaluating the stage of diseases and tailoring drug treatments. The functional cellular immunity test is a promising method to establish the diagnosis of immune dysfunctions. The conventional functional cellular immunity test involves measurements of the capacity of peripheral blood mononuclear cells to produce pro-inflammatory cytokines when stimulated ex vivo. However, this “bulk” assay measures the overall reactivity of a population of lymphocytes and monocytes, making it difficult to pinpoint the phenotype or real identity of the reactive immune cells involved. In this research, we …
Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu
Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu
Weiqiang Chen
Circulating tumor cells (CTCs) detached from both primary and metastatic lesions represent a potential alternative to invasive biopsies as a source of tumor tissue for the detection, characterization and monitoring of cancers. Here we report a simple yet effective strategy for capturing CTCs without using capture antibodies. Our method uniquely utilized the differential adhesion preference of cancer cells to nanorough surfaces when compared to normal blood cells and thus did not depend on their physical size or surface protein expression, a significant advantage as compared to other existing CTC capture techniques.
Effect Of Paired Apertures In A Periodic Hole Array On Higher Order Plasmon Modes, Fang-Tzu Chuang
Effect Of Paired Apertures In A Periodic Hole Array On Higher Order Plasmon Modes, Fang-Tzu Chuang
Fang-Tzu Chuang
We demonstrate that the transmission of higherorder surface plasmon modes in the mid-infrared range can be enhanced through rectangular hole array on the basis of paired apertures. Experiments prove that enhanced high-order transmission can be generated by either identical shapes or combinations of different hole shapes in pairs. The structure factor is adopted to explain the observed intensity of enhanced transmission. Numerical simulations of the enhanced secondorder mode verify a significant field enhancement in a unit cell of pairs. It is clarified that the separation between the paired apertures and the paired resonance is the key to determine certain higher-order …
Two Infrared Emission Modes With Different Wavelengths And Orthogonal Polarization In A Waveguide Thermal Emitter, Fang-Tzu Chuang
Two Infrared Emission Modes With Different Wavelengths And Orthogonal Polarization In A Waveguide Thermal Emitter, Fang-Tzu Chuang
Fang-Tzu Chuang
This study investigates a Au/SiO2/Au waveguide thermal emitter incorporating a metallic grating embedded in the SiO2 layer. The metal grating acts as a beam splitter, dividing the device into two waveguide structures determined by the polarization of the waveguide modes. The thermal radiation spectrum exhibits two peaks with orthogonal polarization. The emitted wavelengths of the two waveguide modes can be adjusted by controlling the thickness of the SiO2 layers on both sides of the metallic grating during the fabrication process. The emission peaks have ratios of the full width at half maximum to the peak wavelength of 0.057 and 0.05 …
Nanoprojection Lithography Using Self-Assembled Interference Modules For Manufacturing Plasmonic Gratings, Fang-Tzu Chuang
Nanoprojection Lithography Using Self-Assembled Interference Modules For Manufacturing Plasmonic Gratings, Fang-Tzu Chuang
Fang-Tzu Chuang
Abstract—A new nanoprojection lithography (NPL) is proposed to manufacture plasmonic nanogratings. Here, low-cost self-assembly elastomeric polydimethylsiloxane wavy structures are used as the interference modules, with their periods and amplitudes largely controlled by the applied mechanical strain in the synthesis process. Well defined plasmonic grating couplers with desired feature sizes and wavelengths of operation were obtained. This NPL may enable large-area and flash manufacturing of plasmonic nanogratings with tunable array periods.
Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu
Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu
Weiqiang Chen
Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type …
Self-Assembled Rippling Structure Based On Metal-Elastomer Composite For Tunable Plasmonics, Fang-Tzu Chuang
Self-Assembled Rippling Structure Based On Metal-Elastomer Composite For Tunable Plasmonics, Fang-Tzu Chuang
Fang-Tzu Chuang
We demonstrate that a periodic metallic wavy-structure can be easily fabricated on elastomeric polydymethylsiloxane (PDMS) substrates. The metallic wavy-structures are self-assembly formed by thermal evaporation of Ag on PDMS without any lithography processes. The size of the PDMS substrate with an aspect ratio (the ratio of length to width) higher than 2 are found to be necessary to self-assemble the one-dimensional metallic wavy-structure. The period of the wavy-structure is controllable by varing the thickness of the deposited silver film. The elastomeric- gratings can excite surface plasmon on Ag/air interfaces; the resonant wavelength can be tuned to a range of 3.5% …
Localized Shape Resonance On Silver Film Perforated By H-Shaped And More Complex Shaped Hole Arrays, Fang-Tzu Chuang
Localized Shape Resonance On Silver Film Perforated By H-Shaped And More Complex Shaped Hole Arrays, Fang-Tzu Chuang
Fang-Tzu Chuang
The experimental results of light transmission through periodic array of H-shaped hole and more complicated hole which is a combination of multiple U shape are demonstrated. The observations indicate that the localized shape resonance in the longest resonant length of unfolded U-shaped part of the hole always appears. However, localized modes resonant in smaller U-shaped length don't always appear. Localized mode with non-U-shaped resonant path cannot be seen in our sample. In addition, localized mode with different order and resonant path can be excited by different polarized light.