Browsing by Author "Huang, Cheng-Sheng"

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An EWOD-based micro diluter with high flexibility on dilution ratio
(2017-08-01)
Wang, Ying-Bin
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Huang, Jun-Hao
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Lee, Meng-Shiue
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Huang, Cheng-Yeh
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Huang, Cheng-Sheng
Dilution is a common procedure in biological and chemical analyses to perform tests at different concentrations. In previously reported micro diluters, although they could provide a wide dilution range, only limited dilution ratios were demonstrated, i.e. low flexibility in dilution ratio. Here, a droplet-based micro diluter with high flexibility on dilution ratio is proposed, fabricated, and tested. Through combination of five different electrode sizes using electrowetting-on-dielectric (EWOD) technique, the proposed micro diluter can provide 49 dilution ratios at dilution range from 1/2 to 1/50. Experimental results verify that different dilution ratios can be successfully generated, even at the most difficult low concentration range. Comparing to the design with equal electrode size in conventional EWOD-based microfluidic chip, the proposed design with unequal electrode sizes can reduce the operation steps to achieve high flexibility on dilution ratios efficiently.
Chip-size wavelength detector based on a gradient grating period guided-mode resonance filter
(2016-01-01)
Lin, Hsin-An
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Hsu, Hsin-Yun
;
Huang, Cheng-Sheng
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機械工程學系
;
Department of Mechanical Engineering
In this study, we designed, fabricated and demonstrated a compact wavelength detection system based on a gradient grating period guided-mode resonance filter (GGP-GMRF) mounted on a linear charge-coupled device (CCD) camera. The GGP-GMRF was first fabricated through nanoreplica molding on a plastic substrate, followed by the deposition of a thin TiO2 film. The grating periods of the GGP-GMRF vary from 250 to 550 nm with a 2 nm increment in each period consisting of 100 cycles. The results show that a 6 mm long GGP-GMRF has a filtering range of 506 to 915 nm. Upon illumination, the GGP-GMRF reflects a particular wavelength of light resulting in the minimum transmission of that wavelength. Hence, the GGP-GMRF provides a spatially dependent minimum transmission depending on the wavelength of the incident light. The linear CCD underneath the GGP-GMRF measures the transmitted intensity, and the wavelength of the incident light can be correlated with the location of the minimum intensity. For the demonstrated GGP-GMRF and CCD system, a spectral resolution of 1 nm can be achieved.
Compact spectrometer system based on a gradient grating period guided-mode resonance filter
(2016-05-16)
Lin, Hsin-An
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Hsu, Hsin-Yun
;
Chang, Chih-Wei
;
Huang, Cheng-Sheng
;
機械工程學系
We demonstrate a compact spectrometer system by using a gradient grating period guided-mode resonance filter-mounted on a linear photodetector array-that exhibits spatially dependent resonance characteristics; a specific incident wavelength is reflected such that the underlying array pixels measure minimum intensity. A precalibrated transmission efficiency matrix is used to determine each pixel's transmission efficiency for specific wavelengths. Unknown spectral information can be calculated from the measured intensity. Grating periods of 250-388 nm in 2-nm increments are used in each 100-cycle period. Device length is 2.23 mm. Spectral range of 506-700 nm is measurable with 1-nm resolution. (C) 2016 Optical Society of America
Compact Wavelength Detection System Based on a Gradient Grating Period Guided-Mode Resonance Filter
(2016)
Lin, Hsin-An
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Hsu, Hsin-Yun
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Huang, Cheng-Sheng
;
機械工程學系
;
Department of Mechanical Engineering
We designed a linear filter based on a gradient grating period guided-mode resonance. By incorporating this device with a photodetector, the system can measure wavelength ranging from 500 to 700 nm with 1 nm resolution.
Design and Fabrication of Compact Spectrometer based on Gradient Grating Period Guided-Mode Resonance Filter
(2017-01-01)
Lin, Hsin-An
;
Hsu, Hsin-Yun
;
Chang, Chih-Wei
;
Huang, Cheng-Sheng
;
機械工程學系
We designed and fabricated a compact spectrometer based on a gradient grating period guided-mode resonance filter (GGP-GMRF). The GGP-GMRF of 2.23 mm long consisted of gratings with periods varying from 250-388 nm in 2-nm increments. With such compact size, the device can measure spectrum ranging from 506 to 700 nm.
Droplet-based label-free detection system based on guided-mode resonance and electrowetting-on-dielectric for concentration measurement
(2017-05-01)
Wang, Ying-Bin
;
Su, Lin-Yun
;
Fu, Ching-Shu
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Huang, Cheng-Sheng
;
Hsu, Wensyang
We demonstrate a digital microfluidic system with an on-chip detection capability that is based on a guided-mode resonance filter (GMRF). Versatile droplet manipulation was achieved through the electrowetting-on-dielectric (EWOD) technique. GMRF was fabricated through replica molding and soft lithography, and the EWOD chip was fabricated through a typical photolithography process. Droplets measuring 1.125 mu L were used to demonstrate merging, mixing, and cutting, and to achieve twofold and Threefold dilutions, and were then transported to the GMRF region for concentration measurement. The bulk sensitivity of GMRF is approximately 90 nm RIU-1 1 [17494nm/(g/L)], resulting in a minimum detectable concentration of 4.66 x 10(-5) g/L for a sucrose solution. (C) 2017 The Japan Society of Applied Physics
Flexible Linear and Angular Displacement Sensor Based on a Gradient Guided- Mode Resonance Filter
(2018-12-15)
Wang, Yen-Chieh
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
This paper reports a method for micrometer-scale linear and angular displacement measurement based on a gradient grating period guided-mode resonance (GGP-GMR) filter. When the filter is mounted on a moving or rotating object, the displacement on the object can be observed through the changes in the resonant wavelength, which are detected by the GGP-GMR filter. In this paper, the GGP-GMR filter comprised grating periods from 250 to 550 nm with 2-nm increments. Each period comprised 100 repeated cycles, resulting in a total length of 6 mm. For linear displacement, we achieved an average sensitivity of 67 nm/mm for a detection range of 6 mm and a theoretical limit of detection of 3 mu m. To demonstrate the measurement of angular displacement, the GGP-GMR filter was attached to a cylinder with a diameter of 8 cm. The experimental results revealed an average sensitivity of 51.7 nm/degrees for a range of 7 degrees and an experimental limit of detection of 0.002 degrees.
Hydrogel-based zinc ion sensor on optical fiber with high resolution and application to neural cells
(2020-08-15)
Tsai, May-Jywan
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Cheng, Henrich
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Ho, Hsin-Hsien
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Lin, Peng-Wei
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Liou, Dann-Ying
Solid-state zinc ion sensor is developed with high enough resolution and reproducibility for the potential application in brain injury monitoring. An optical diffuser is incorporated into the zinc ion sensor based on optical fiber and hydrogel doped with the fluorescent zinc ion probe molecule meso-2,6-Dichlomphenyltripyrrinone (TPN-Cl-2). The diffuser transforms the high-peak-intensity excitation light near the fiber end into a broad light with moderate local intensity to reduce the degradation of the probe molecule. Reversible detection can be reached for 1, 2, and 5 mu m (10(-6) Molar), with slopes 0.3, 0.6, and 0.8 respectively. This is the pathophysiological concentration range after brain injury. The sensor is applied to neuron-glial cultures and macrophage under the stimulation of lipopolysaccharide (LPS), KCl and oxygen/glucose deprivation (OGD) that reflect inflammation, depolarization and ischemia respectively, mimicking events after brain injury. The zinc ion level is raised to 4-5 mu m after LPS treatment, and then reduced to <3 mu m after the co-treatment with the herbal drug silymarin. The results suggest the conditions of the neural cells under stress can be monitored.
Integration of a guided-mode resonance filter with microposts for in-cell protein detection
(2016)
Tu, Yi-Kai
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Tsai, Meng-Zhe
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Lee, I-Chin
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Hsu, Hsin-Yun
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Huang, Cheng-Sheng
We present an integrated microfluidic system consisting of a label-free biosensor of a guided-mode resonance filter (GMRF) and a microfluidic channel with a micropost filter. The GMRF was fabricated through replica molding using an ultraviolet-curable polymer and a plastic substrate. An array of microposts (a diameter and height of 26.5 and 56 mu m, respectively, and a spacing between 7.5 and 9.5 mu m), fabricated on a silicon substrate through photolithography, was used as the filter. A double-sided tape was used to laminate the GMRF and a microfluidic chip such that the integrated device provides two functions: filtration of the cell debris and quantification of the in-cell protein concentration. By measuring the changes in the resonant wavelength from the GMRF, the detection of beta-actin in an unprocessed lysed cell sample was demonstrated; the cell debris was separated using the micropost filter to prevent false measurement.
Linear Variable Filter Based on a Gradient Grating Period Guided-Mode Resonance Filter
(2016-05-01)
Lin, Hsin-An
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
In this letter, we fabricated and characterized a linear variable filter based on a guided-mode resonance filter (GMRF) with gradient grating periods. The GMRF was first fabricated through nanoreplica molding on a plastic substrate, which was followed by the deposition of a thin TiO2 film. The grating periods of the GMRF vary from 250 to 550 nm with a 2-nm increment in each period consisting of 100 cycles. The results show that a 6-mm-long GMRF has a filtering range of 506-915 nm.
Optimization of a guided-mode resonance filter by varying the thickness of the buffer layer
(2016-03-10)
Hsu, Hsiang I.
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Wu, Po-Tsung
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
In this Letter, we demonstrate that by adjusting the thickness of the buffer layer, the optical responses of a guided-mode resonance filter (GMRF) can be improved for sensor applications. The GMRF is fabricated using a replica molding with a plastic substrate and a UV-curable polymer. SiO2 buffer layers of different thicknesses are deposited before the waveguide-layer deposition. The sensitivity of the GMRFs decreasds slightly with-increasing SiO2 layer thickness. By contrast, the full width at half-maximum reduces substantially with increasing SiO2 layer thickness, resulting in the improvement of the overall figure of merit.
Photonic crystal micropost as a microarray platform
(2016-02-08)
Chang, Chih-Wei
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
This study demonstrates a photonic crystal micropost (PCMP) substrate for microarray applications. The substrate comprises an array of circular MPs with a PC on top of these MPs. This substrate enables biomolecule-containing droplets to form a composite contact upon deposition, thus allowing biomolecules to be attached on only the MPs, forming spots. When the device (PC) is excited on resonance, the electric field intensity is enhanced on only the top surface of the MPs. This enables the fluorescence intensities to be enhanced up to 5.50x; principally, this enhancement does not engender an increase in the background (intensity outside MP or spots) and noise intensities. The PCMP substrate enhances the spot intensity and minimizes the background intensity, enabling the detection of lower concentration analytes. (C) 2016 Optical Society of America
Photonic crystal-enhanced fluorescence through the extraction of dually polarized modes
(2015-03-01)
Wu, Yu-An
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Wu, Po-Tsung
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
In this Letter, we demonstrate that fluorescence detection by using surface-bound fluorescent molecules can be enhanced by coupling the fluorescence emission with dually polarized resonant modes of a photonic crystal (PC) substrate. The PC was fabricated through nanoreplica molding by using a plastic substrate. It was designed such that the transverse magnetic (TM)- and transverse electric (TE)-polarized resonance coincided at a specific combination of the incident angle and the illumination wavelength. During excitation, the nonpolarized emission from cyanine-5 was simultaneously coupled with the TE and TM resonant modes and reradiated into the detection instrument, increasing the fluorescence collection efficiency and thus, enhancing the fluorescence detection. (C) 2015 Optical Society of America
Real-time CRP detection from whole blood using micropost-embedded microfluidic chip incorporated with label-free biosensor
(2018-01-21)
Tsai, Meng-Zhe
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Hsiung, Chan-Te
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Chen, Yang
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Huang, Cheng-Sheng
;
Hsu, Hsin-Yun
We demonstrate the detection of C-creative protein (CRP) from whole blood samples without sample pretreatment by using a lab-on-a-chip system consisting of a microfluidic chip and a label-free biosensor. The microfluidic chip includes an array of microposts for filtering blood cells and allows only plasma to flow through and reach the guided-mode resonance (GMR) biosensor for real-time monitoring. The developed GMR sensor can achieve a bulk sensitivity of 186 nm RIU-1, which supports a limit of detection of 3.2 ng mL(-1) for recombinant CRP spiked in human serum. The results are comparable with those obtained using enzyme-linked immunosorbent assay. In addition, we demonstrate the efficacy of filtration of blood cells using microposts and simultaneous measurement of CRP concentration using a GMR sensor by using whole blood and plasma samples.
Refractive Index Sensor Based on a Gradient Grating Period Guided-Mode Resonance
(2019-02-01)
Hsiung, Chan-Te
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Huang, Cheng-Sheng
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機械工程學系
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Department of Mechanical Engineering
In this letter, we introduce a novel refractive index sensor based on gradient grating period guided-mode resonance (GGP-GMR). Rather than a constant grating period, as in typical GMR, GGP-GMR comprises a grating period varying in increments of 2 nm. For grating variation from 386 to 392 nm, a detection range of 0.109 RIU with a bulk sensitivity of 1433.7 mu m/RIU and theoretical and experimental detection limits of 5.58 x 10(-3) and 10(-2) RIU, respectively, can be achieved. Several tactics that can be readily adopted are suggested to improve the limit of detection by an order of 10(-4) RIU, sufficient for detecting many clinically relevant biomarkers. The readout system requires a narrow band of light and a simple charge-coupled device combined with the compact design of the GGP-GMR sensor, which eases the miniaturization of the system for handheld devices as well as its integration with smartphones.
Resonant Wavelength Shift Detection System Based on a Gradient Grating Period Guided-Mode Resonance
(2018-08-01)
Chang, Chih-Wei
;
Chen, Shi-Ting
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Lin, Yi-Ming
;
Huang, Cheng-Sheng
;
機械工程學系
A resonant wavelength detection system based on a gradient grating period guided-mode resonance (GGP-GMR) filter and a linear charge-coupled device is demonstrated. The GGP-GMR used in this work consists of a subwavelength grating structure with a grating period that varies from 250 to 550 nm in increments of 2 nm. We successfully demonstrate that by using this system, we can monitor the shift in a sensor's dip wavelength caused by different sucrose concentrations. This technology has the potential to replace the spectrometer used in most optical biosensor systems. Given its compactness, the system can be integrated with lab-on-a-chip systems for numerous biosensing applications.
Resonant wavelength shift detection system based on a gradient grating period guided-mode resonance filter
(2018-01-01)
Chang, Chih-Wei
;
Chen, Shi-Ting
;
Wang, Yen-Chieh
;
Huang, Cheng-Sheng
;
機械工程學系
A resonant wavelength detection system based on a gradient grating period guided-mode resonance (GGP-GMR) filter and a linear charge-coupled device is demonstrated. The GGP-GMR used in this work consists of a subwavelength grating structure with a grating period varying from 250-550 nm in increments of 2 nm. We successfully demonstrate that by using this system, we can monitor the shift in a biosensor's dip wavelength caused by different sucrose concentrations. This technology has the potential to replace a bulky and expensive spectrometer used in most optical biosensor systems. Given its compactness, the system can be integrated with lab-on-a-chip systems for numerous biosensing applications.