Browsing by Author "Yao, Da-Jeng"

Now showing 1 - 14 of 14

A 0.5V 1.27mW Nose-on-a-Chip for Rapid Diagnosis of Ventilator-Associated Pneumonia
(2014-01-01)
Tang, Kea-Tiong
;
Chiu, Shih-Wen
;
Shih, Chung-Hung
;
Chang, Chia-Ling
;
Yang, Chia-Min
A highly efficient bead extraction technique with low bead number for digital microfluidic immunoassay
(2016-01)
Huang, Cheng-Yeh
;
Tsai, Po-Yen
;
Lee, I-Chin
;
Hsu, Hsin-Yun
;
Huang, Hong-Yuan
Here, we describe a technique to manipulate a low number of beads to achieve high washing efficiency with zero bead loss in the washing process of a digital microfluidic (DMF) immunoassay. Previously, two magnetic bead extraction methods were reported in the DMF platform: (1) single-side electrowetting method and (2) double-side electrowetting method. The first approach could provide high washing efficiency, but it required a large number of beads. The second approach could reduce the required number of beads, but it was inefficient where multiple washes were required. More importantly, bead loss during the washing process was unavoidable in both methods. Here, an improved double-side electrowetting method is proposed for bead extraction by utilizing a series of unequal electrodes. It is shown that, with proper electrode size ratio, only one wash step is required to achieve 98% washing rate without any bead loss at bead number less than 100 in a droplet. It allows using only about 25 magnetic beads in DMF immunoassay to increase the number of captured analytes on each bead effectively. In our human soluble tumor necrosis factor receptor I (sTNF-RI) model immunoassay, the experimental results show that, comparing to our previous results without using the proposed bead extraction technique, the immunoassay with low bead number significantly enhances the fluorescence signal to provide a better limit of detection (3.14 pg/ml) with smaller reagent volumes (200 nl) and shorter analysis time (<1 h). This improved bead extraction technique not only can be used in the DMF immunoassay but also has great potential to be used in any other bead-based DMF systems for different applications. (C) 2016 AIP Publishing LLC.
An Implantable Drug-delivery System on a Chip
(2015-01-01)
Lee, Meng-Shiue
;
Yao, Da-Jeng
;
Hsu, Wensyang
;
機械工程學系
;
Department of Mechanical Engineering
An implantable system for drug delivery provides a new strategy for drug therapy, and typically involves a microfluidic chip produced with micro or nano-technology. Implantable systems have the flexibility to conform various schemes of drug release, including zero order, pulsatile, and on demand dosing, as opposed to a standard sustained release profile. Such an implantable system is classified as allowing either controllable or uncontrollable drug release after implantation, so an active or passive delivery system respectively. The performance and related applications of these systems vary. The key points of each technology are highlighted such as performance, working principle, fabrication methods, and dimensional constrains. We here review the implantable drug-delivery system in current research with a focus on application and chip performance, and comparison for passive and active delivery system.
Bead-Based Digital Microfluidic Immunoassay for IL-1 beta Detection in Embryo Culture Medium
(2017-01-01)
Tseng, Hsueh-Yang
;
Jiang, Yi-Ting
;
Huang, Cheng-Yeh
;
Lee, Meng-Shiue
;
Hsu, Wensyang
One of the challenges in IVF treatment is to improve the pregnancy rate of selective single embryo implantation. The concentration of IL-1 beta in embryo culture medium may help to predict pregnancy rate. Clinically, each embryo can only get small amount of sample size. However, the traditional immunoassay cannot detect biomarkers in such small sample sizes. Therefore, we combined immunoassay with the bead-based digital microfluidic chip. The chip has two advantages, low sample requirement and low detection limit. We established the mouse IL-1 beta calibration curve, confirm the Human Tubal Fluid (HTF) does not influence the test result and demonstrate that mouse IL-1 beta in clinical mouse embryo culture medium is positively correlate to cultured days. This device has a great potential for increasing IVF pregnancy rates.
Detection of Particulate Matter of Size 2.5 m with a Surface-Acoustic-Wave Sensor Combined with a Cyclone Separator
(2018-08-01)
Kuo, Fung-Yu
;
Lin, Ying-Chen
;
Ke, Ling-Yi
;
Tsai, Chuen-Jinn
;
Yao, Da-Jeng
A device to monitor particulate matter of size 2.5 m (PM2.5) that has been designed and developed includes a surface-acoustic-wave sensor operating in a shear horizontal mode (SH-SAW) combined with a cyclone separator. In our tests, aerosols generated as incense smoke were first separated and sampled inside a designed cyclone separator; the sampled PM2.5 was then introduced into the sensing area of an SH-SAW sensor for detection. The use of microcentrifuge tubes as a cyclone separator effectively decreases the size and power consumption of the device; the SAW sensor in a well design and operating at 122 MHz was fabricated with MEMS techniques. After an explanation of the design of the cyclone separator, a simulation of the efficiency and the SAW sensor detection are discussed. A microcentrifuge tube (volume 0.2 mL, inlet and outlet diameters 0.5 mm) as a separator has separation cutoff diameters 50% (d(50)) at 2.5 m; the required rate of volumetric flow at the inlet is 0.125 LPM, according to simulation with computational fluid dynamics (CFD) software; the surface-acoustic-wave (SAW) sensor exhibits sensitivity approximately 9 Hz/ng; an experiment for PM2.5 detection conducted with the combined device shows a strong positive linear correlation with a commercial aerosol monitor. The limit of detection (LOD) is 11 g/m(3) with sample time 160 s and total detection duration about 5 min.
Digital Microfluidic Dynamic Culture of Mammalian Embryos on an Electrowetting on Dielectric (EWOD) Chip
(2015-05-01)
Huang, Hong-Yuan
;
Shen, Hsien-Hua
;
Tien, Chang-Hung
;
Li, Chin-Jung
;
Fan, Shih-Kang
Current human fertilization in vitro (IVF) bypasses the female oviduct and manually inseminates, fertilizes and cultivates embryos in a static microdrop containing appropriate chemical compounds. A microfluidic microchannel system for IVF is considered to provide an improved in-vivo-mimicking environment to enhance the development in a culture system for an embryo before implantation. We demonstrate a novel digitalized microfluidic device powered with electrowetting on a dielectric (EWOD) to culture an embryo in vitro in a single droplet in a microfluidic environment to mimic the environment in vivo for development of the embryo and to culture the embryos with good development and live births. Our results show that the dynamic culture powered with EWOD can manipulate a single droplet containing one mouse embryo and culture to the blastocyst stage. The rate of embryo cleavage to a hatching blastocyst with a dynamic culture is significantly greater than that with a traditional static culture (p<0.05). The EWOD chip enhances the culture of mouse embryos in a dynamic environment. To test the reproductive outcome of the embryos collected from an EWOD chip as a culture system, we transferred embryos to pseudo-pregnant female mice and produced live births. These results demonstrate that an EWOD-based microfluidic device is capable of culturing mammalian embryos in a microfluidic biological manner, presaging future clinical application.
Direct measurement of hot-spot temperature in flip-chip solder joints under current stressing using infrared microscopy
(2008-08-01)
Hsiao, Hsiang-Yao
;
Liang, S. W.
;
Ku, Min-Feng
;
Chen, Chih
;
Yao, Da-Jeng
Several simulation studies reported that a hot spot exists in flip-chip solder bumps under accelerated electromigration. Yet, there are no experimental data to verify it. In this paper, the temperature distribution during electromigration in flip-chip SnAg3.5 solder bumps is directly inspected using infrared microscopy. Two clear hot spots are observed in the bump. One is located at the region with peak current density and the other one is at the bump edge under the current-feeding metallization on the chip side. Under a current stress of 1.06x10(4) A/cm(2), the temperature in the two hot spots are 161.7 and 167.8 degrees C, respectively, which surpass the average bump temperature of 150.5 degrees C. In addition, the effect of under-bump-metallization (UBM) thickness on the hot spots is also examined. It indicates that the hot-spot temperature in the solder bump increases for the solder joints with a thinner UBM. Electromigration test indicates that these hot spots have significant influence on the initial failure location. (c) 2008 American Institute of Physics.
EMBRYO LAB CHIP TAKING ADVANTAGE OF MICROFLUIDICS AND CELL CO-CULTURING
(2015)
Liu, Cheng-Hsien
;
Chang, Kuo-Wei
;
Chang, Pei-Yu
;
Sung, Yi-Jung
;
Huang, Hong-Yuan
This research serves as an in vitro platform for fertilization and embryonic development. Thin polydimethylsiloxane ( PDMS) membrane was etched to create an array of through-holes, and sandwiched between two PDMS channels to form an upper chamber and lower chamber. This device integrates the concentration gradient design and perfusion system for proposed embryo coculture with stromal cells.
Fabrication of 3D Microfluidic Chip integrating Concentration gradient design and Perfusion system for Embryo coculture with Stromal cells
(2012-01-01)
Chang, Pei-Yu
;
Chang, Kuo-Wei
;
Lin, Ciou-Wen
;
Shih, Po-Chen
;
Liu, Cheng-Hsien
Fabrication of 3D chip that enables cell culture under continuous flow perfusion and repeated in situ observation by light microscopy is described. Thin polydimethylsiloxane PDMS) membrane was etched to create an array of through-holes, and sandwiched between two PDMS channels to form an upper chamber and lower chamber. Thus we fabricated a 3D microfluidic chip which integrates the concentration gradient design and perfusion system for proposed embryo coculture with stromal cells.
Influence of Cu column under-bump-metallizations on current crowding and Joule heating effects of electromigration in flip-chip solder joints
(2012-02-15)
Liang, Y. C.
;
Tsao, W. A.
;
Chen, Chih
;
Yao, Da-Jeng
;
Huang, Annie T.
The electromigration behavior of SnAg solder bumps with and without Cu column under-bump-metallizations (UBMs) has been investigated under a current density of 2.16 x 10(4) A/cm(2) at 150 degrees C. Different failure modes were observed for the two types of samples. In those without Cu column UBMs, when SnAg solder bumps that had implemented 2 mu m Ni UBMs were current stressed at 2.16 x 10(4) A/cm(2), open failure occurred in the bump that had an electron flow direction from the chip side to the substrate side. However, in those with Cu column UBMs, cracks formed along the interface of Cu6Sn5 intermetallic compounds and the solder on the substrate side in the Sn-3.0Ag-0.5Cu solder bump that had an electron flow direction from the substrate side to the chip side. A three-dimensional simulation of the current density distribution was performed in order to obtain a better understanding of the current crowding behavior in solder bumps. The current crowding effect was found to account for the void formation on both the chip and the substrate side for the two kinds of solder bumps. One more important finding, as confirmed by infrared microscopy, is that the alleviation of current crowding by Cu column UBMs also helped decrease the Joule heating effect in solder bumps during current stressing. Therefore, the measured failure time for the solder joints with Cu column UBMs appears to be much longer than that of the ones with the 2 mu m Ni UBMs. (C) 2012 American Institute of Physics. [doi:10.1063/1.3682484]
Innovation of Digitalized Microfluidic System with Electrowetting-on-Dielectric (EWOD) Chip Used in In Vitro Embryo Culture System.
(2012-03-01)
Huang, Hong-Yuan
;
Yao, Da-Jeng
;
Huang, Hung-Ju
;
Fan, Shih-Kang
;
Li, Chin-Jung
Magnetic bead-based DNA detection with multi-layers quantum dots labeling for rapid detection of Escherichia coli O157:H7
(2008-12-01)
Liu, Yi-Ju
;
Yao, Da-Jeng
;
Chang, Hwan-You
;
Liu, Chien-Ming
;
Chen, Chih
This work demonstrated the feasibility of detecting 250 zM Escherichia coli O157:H7 eaeA target DNA by using a magnetic bead-based DNA detection assay with designed labeling strategy within 40-60 min. The magnetic beads were used as the solid support for the binding probe and isolated the target DNA from the sample. The detection signals could be amplified from the multi-layers biotin-streptavidin conjugated quantum dots based on binding with specific designed biotinlyted linker. This assay method would provide a simple, rapid, and ultra-sensitive detection method for DNA or other biomolecular analysis. (C) 2008 Elsevier B.V. All rights reserved.
Simultaneous detection of two growth factors from human single-embryo culture medium by a bead-based digital microfluidic chip
(2020-02-15)
Lee, Meng-Shiue
;
Hsu, Wensyang
;
Huang, Hong-Yuan
;
Tseng, Hsueh-Yang
;
Lee, Chia-Tung
The measurement of growth factors released in a culture medium is considered to be an attractive non-invasive approach, apart from the embryo morphology, to identify the condition of an embryo development after fertilization in vitro (IVF), but the available embryo culture medium in the current method is only a few microlitres. This small sample volume, also of small concentration, makes difficult the application of a conventional detection method, such as an enzyme-linked immunosorbent assay (ELISA). A reliable detection of the growth factor from each embryo culture medium of such a small concentration hence remains a challenge. Here for the first time we report the results of measurement of not just one, but two, growth factors, human IL-1 beta and human TNF-alpha, from an individual droplet of embryo culture medium with a bead-based digital microfluidic chip. The required sample volume for a single measurement is only 520 nL; the total duration of the on-chip process is less than 40 min. Using the culture media of human embryos with normal morphologic features, we found that the concentrations of TNF-alpha change little from day 3 to day 5-6, but the concentrations of IL-1 beta for some embryos might double from day 3 to day 5-6. For other embryos even with similar normal morphologic features, some growth factors, such as IL-1 beta, might exhibit different expressions during the culture period. Those growth factors could serve to distinguish the development conditions of each embryo, not merely from an observation of embryo morphology.
Womb-on-a-chip biomimetic system for improved embryo culture and development
(2016-04-01)
Chang, Kuo-Wei
;
Chang, Pei-Yu
;
Huang, Hong-Yuan
;
Li, Chin-Jung
;
Tien, Chang-Hung
The 3D biomimetic microsystem described in this research integrates various functions of the fallopian tube to serve as an in vitro platform for fertilization and embryonic development. This device mimics the in vivo embryo-endometrial stromal cell monolayer coculture to enhance the group culture of embryos and mechanically culture the embryos in a dynamic manner to enhance their development. The microdevice presented here is compared with static culture for embryonic development rate in the presence and absence of epithelial cells. The results suggest that the dynamic biomimetic microsystem enhances the rate of embryo development, providing a culture environment that closely mimics the in vivo microenvironment. This all-in-one biomimetic microsystem has the potential to replace the present embryo culture platforms used for assisting in vitro fertilization. (C) 2015 Elsevier B.V. All rights reserved.