http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
45°의 확장과 축소 배열의 마이크로 채널을 이용한 크기에 따른 입자 분리 연구
곽봉섭(B.S. Kwak),이성한(S.H. Lee),허윤석(Y.S. Heo) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.12
With the recent development of the micro-particle separation in microfluidic system it has been applied in various fields. We developed a new microfluidic device which 100 repeated 45° angled expansion structures and contraction channels for particle separation with high-throughput. This micro channel use the combination of the momentum change-induced inertial force and the inertial lift force acting on micro particles according to particle Reynolds number. 2μm, 6μm, 13μm diameter particles were used to this study. 13μm particles focus on the centerline of channel and 2μm and 6μm particles move toward both side wall of micro channel in 260μL/min of flow rate.
마이크로 채널에서 관성력을 이용한 혈중 종양 세포의 크기에 상응하는 입자 분리 연구
곽봉섭(Bongseop Kwak),이성한(Sung Han Lee),허윤석(Yun Seok Heo) 한국가시화정보학회 2016 한국가시화정보학회 학술발표대회 논문집 Vol.2016 No.12
It is well known that CTCs(Circulating Tumor Cells) separation is critical for cancer diagnoses and therapy. 1 - 1,000 CTCs exist in 1mL volume of cancer patient blood while 5 × 10<SUP>9</SUP> erythrocytes and 4 × 10<SUP>6</SUP> leukocytes exist in thereto. Because of the rarity of CTCs, CTCs enrichment process is necessary before the detection of them. We used the particles corresponding the size and density of cells and achieved particle separation with high-throughput in micro channel. The inertial forces(inertial lift force and momentum change induced inertial force) are used to particle separation at particular flow rate in this microchannel. We expand that this microchannel can apply various cell separation.
Fully Automated Molecular Diagnosis by a Novel Cartridge-based Platform
권오원,이강호,곽봉섭,윤종수,정기수,이동규 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.5
A novel cartridge-based platform was developed to perform fully automated sample preparation, amplification, and analysis of nucleic acids. The cartridge consists of three layers: multiple reagent chambers, a mixing reservoir, and elutes and waste chambers. The fluidic manipulation and solution mixing inside the cartridge were controlled by motor systems. After loading a sample specimen, each reagent solution in the chambers of the cartridge was sequentially injected into the mixing reservoir. Extracted nucleic acids were captured by magnetic beads and transferred into a small eluates chamber. Automated sample preparation and isothermal amplification of nucleic acids for pathogenic bacteria were demonstrated in this all-in one cartridge platform. This cartridge system provides rapid and reproducible sample preparation in comparison with manual methods. In addition, real-time detection of isothermal amplification using the implemented photometric system was compared with that of using a commercial polymerase chain reaction (PCR) device. This system has the potential to become a more reliable diagnostic tool for fast detection of contagious, foodborne, and emergency point-of-care (POC) diseases.
최서연,이정현,곽봉섭,김영우,이준상,최종순,정효일 한국바이오칩학회 2015 BioChip Journal Vol.9 No.2
This is a one-step POC biosensor that guarantees rapid assay times, low-cost analysis, simplehandling, stability, and is easy to mass product. However, it has several drawbacks such as limited samplevolume and relatively low sensitivity. To overcome these disadvantages, we have designed and fabricatedthe μ-PAD to confine fluid flow by creating a hydrophobic channel in the paper to improve the sensitivity. The channel pattern was drawn by a computer-aided design program and directly printed by a commercially available wax printer which generates the hydrophobic channel pattern. While maintaining a constant sample, absorption, and conjugation pad, the width of the detection pad was reduced from 5 mm to 2 mm at intervals of 1 mm. The intensity of bands from the single- and double-orifice patterns increased identically compared with the device with no orifice. The relative intensity of the signal bands increased from 141 to 158. Also, numerical simulation was performed to validate the experimental result by using lattice Boltzmann method. We observed that the sensitivity was enhanced at a specific detection pad width (3 mm). Therefore, our simple structural change of the channel led to improve the colorimetric intensity. Cortisol, which is a known stress biomarker, was used to validation the device, an enhanced signal was obtained indicating that our device can be used for the detection psychological stress in humans.
노즐 모양의 미세 유체 채널을 이용한 크기에 따른 입자 분리 연구
이성한(S.H. Lee),곽봉섭(B.S. Kwak),허윤석(Y.S. Heo) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11
Recently the research on the particle separation is going along various method and using in a biomedical application. I have demonstrated the separation of particle using the force balance on the size different micro-particles between inertial and viscous force in a nozzle shape of microchannel. If fluid flow rate maintain high velocity(0.01~1㎧), the Reynolds number can attain very high field and ignored inertial force appear compared with viscous force. And Stokes number is relative to the radius of particle other things being equal, so I can forecast the movement of different size particles and convinced these by simulation and experiment. This technique requires only hydraulic force and has high-throughput due to the high flow rate. Thus this research is useful in the case of using a variety of size cells including circulating tumor cells(CTC) instead of particle.