능동형 박막 광도파로 칼슘 이온 센서의 개발

이수미,강신원,Lee, Su-Mi,Gang, Sin-Won 대한전자공학회 2000 電子工學會論文誌-SC (System and control) Vol.37 No.4

고분자 이온 감응막을 광도파로로 이용한 새로운 형태의 센서소자를 제작하여 칼슘이온의 농도 변화에 따른 그 특성을 평가하였다. 광도파로 소자는 실리카 유리기판에 기존의 반도체 사진식각법 (photolitho-graphy)을 이용하여 도파로가 형성되어질 부분을 에칭한 후 감지막을 스핀코팅법으로 코팅하여, 그 자체를 도파로로 이용한 고속 응답의 새로운 형태의 센서소자를 제작하였다. 도파로로 사용된 감지막은 칼슘이온에 대해 특이성을 가지는 변색성 이온감응물질인 ETH5294, 중성이온감응물질인 K23El, anionic site인 NaTm(CF/sub 3/)/sub 2/PB, 가소제인 DOP 및 PVC-PVAC-PVA 폴리머를 THF 용매에 녹여 스핀 코팅법으로 제작하였다. 여러 가지 변수에 따른 센서의 특성을 평가하기 위하여 도파로의 두께(즉, 감지막의 두께), 변색성 이온감응물질의 농도, 각 모드 변화에 따른 센서의 감응특성을 비교 평가하였다. 제작된 센서는 칼슘이온에 대해 1×10­6∼1M의 측정 범위를 가지며, 1×10­⁴∼1×10­¹M 영역에서 선형성을 가지며, 기존의 광학적 측정 방법인 분광분석법에 비해 높은 감도를 나타냄을 확인하였다. A new functional organic thin film optical waveguide ion sensor is designed, which can select a specific ion, i.e., $Ca^{2+}$ -ion. The sensing membrane was composed of PVC-PVAC-PVA copolymer matrix based on anionic cation-selective chromoionophor(ETH5294), neutral ionophore(K23El), anionic site and plasticizer and it was coated on the etched glass substrate as embeded type optical waveguide itself. The sensor sensitivity dependence on waveguide length and thickness, contence of chromoionophore, and each mode was investigated. And this sensor could detect $Ca^{2+}$ ion in concentrations ranging from 1$\times$10­6~1M(with 0.05M tris-HCI buffer solution of pH7.4) by measuring the absorbance change at 514nm of light. Utilizing thin film membrane, the fast response time and high sensitivity are obtained. Also, it is expected that this sensor can be applied to various biochemical important ions.ons.

소산파를 이용한 다채널 광섬유형 미각센서의 제작 및 기본 맛에 대한 패턴분석

이수미(Su Mi Lee),강신원(Shin Won Kang) 한국센서학회 2000 센서학회지 Vol.9 No.5

N/A In this study, a multichannel taste sensor using the evanescent field absorption in fiber optic was developed, and evaluated its characteristics for several basic taste substances. This sensor is based on the change of evanescent field absorption at the surface of optical fiber core layer. The sensor device was made of a plastic-clad-silica fiber (3M Co., FP-900-UHT, core diameter 400 ㎛) and a middle portion of cladding layer was removed and the surface of stripped fiber core was dip-coated with a sensing membrane. And then, it was determined the difference of evanescent field absorption into the sensing membrane, according to various taste substances and its concentrations variance. The sensing membranes were prepered with six kinds of dyes, were known as potential sensitive dye together with silicone polymer the same refractive index of cladding. Each output patterns were obtained from the sensor devices could be distinguished not only five kinds of basic taste substances such as sweetness, saltiness, sourness, bitterness and umami, but also various mixed taste substances.

소산장 흡수를 이용한 박막 광도파로형 칼륨이온센서

이수미,고광락,강신원 ( Su Mi Lee,Kwang Nak Koh,Shin Won Kang ) 한국센서학회 1997 센서학회지 Vol.6 No.3

A thin film optical waveguide sensor has been developed to measure and analyze quantitatively some inherent optical properties of biochemical substances. In this paper, two different kinds of thickness of thin film waveguide were prepared by RF sputtering of Corning-7059 glass(n = 1.588 at λ = 514nm, Ar laser) on Pyrex glass substrates. We made a sensing membrane coated on the thin film waveguide with the polyvinyl chloride-co-vinyl acetate-co-vinyl alcohol) ( 91 : 3 : 6 ) copolymer membrane based on H^+ -selective chromoionophore and K^+ -selective neutral ionophore and then proposed the thin film opptical waveguide ion sensor which can select a potassium ion. This sensor based on the absorbance change by utilizing chromoionophore and neutral ionophore, which changes their absorption spectrum in the UV-vis region upon complexation of the corresponding ionic species, have been reported. The sensitivity dependence of the proposed sensor on interaction length, waveguide thickness, and content of a chromoionophore was investigated. This sensor has the measurement range of 10^(-6) M∼IM for K^+ concentration and 90% response time of duration within 1 min. Also, our thin film optical waveguide sensor using the evanescent field was investigated as compared with conventional transmission sensor or optode sensor by the optical fiber. The sensitivity of thin-film waveguide K` sensor is higher than that of the conventional transmission sensor. The proposed sensor is expected to be useful to biochemical, medical, environmental inspection and so on.

질소레이저와 광섬유를 이용한 원격제어 실시간 우라늄 농도 측정

이상목,신장수,이수미,고광락,강신원 ( Sang Mock Lee,Jang Soo Shin,Su Mi Lee,Kwang Nak Koh,Shin Won Kang ) 한국센서학회 1997 센서학회지 Vol.6 No.5

The remote real-time uranium concentration analysis using nitrogen laser, optode, photomultiplier and optical fiber is studied. The optode for the remote collection of uranium fluorescence is designed. 1`he fluorescence intensity at time zero is calculated in order to exclude the quenching effect and the temperature fluctuation and used for more precise estimation. The fluorescence change is very sensitive to the uranium concentration change. The method shows the detection limit of 0.06ppm and the linearity between 0.1ppm and 2ppm of the aqueous uranium concentration.

Optode형 glucose 센서의 개발

강신원,고광락,이수미,김수진 경북대학교 센서기술연구소 1997 연차보고서 Vol.1997 No.-

인간의 미각은 단맛 (甘味, sweet taste), 신맛 (酸味, sour taste), 짠맛(鹽味, saline taste), 쓴맛 (苦味, bitter taste)의 4가지 기본요소와 우마미 (Umami)^1)로 이루어져 있다. 본 연구에서는 그 중 글루코오스를 감지할 수 있는 당도 (糖度)센서인 초보적인 미각센서의 개발을 위하여 광섬유를 이용한 optode형의 센서소자를 제작하여 glucose의 농도 1×10 exp (-7) ∼ 1×10 exp (-2) M의 범위에 대해 측정하였다. 본 센서의 측정원리는 광섬유를 통한 광의 전달시 감지막의 글루코오스에 대한 반응에 따른 흡광 특성에 의해 일어나는 출력광의 감소 즉, 소산파의 흡수를 측정하는 원리를 이용하였다. The taste is composed of five fundamental tastes, sweet, sour, saline, bitter taste and umami. This research purposed to develope a glucose sensor, sweet taste sensor. The glucose sensor device used five kinds of dye/PMMA polymer sensing membranes containing five dyes. All experiment processor is based on the pH 7.4, 0.05 M tris-HCl buffer solution and glucose concentration from 1×10 exp (-7) to 1×10 exp (-2) M range. The fiber optode of the sensor device is made of skipped cladding in the fiber's middle site and then coated by dye/PMMA membrane. The principle of the sensor is based on the absorbance change of the evanescent wave of the sensing membrane according to glucose concentration change. In this experiments, we made a response pattern of the glucose sensor system using the evanescent wave.

소산장 흡수를 이용한 다채널 광섬유 미각센서

김수진,이수미,강신원 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

The application of fiber-optic for chemical and biochemical sensing is a field of increasing interest and importance. This work represents new design for taste sensor based on the fiber-optic evanescent field absorption. A 10cm length of plastic-clad-silica(PCS) fiber having a 400μm-diameter was used for fabrication of sensor. The cladding of the fiber were removed from 3cm of the middle portion and coated with a six kinds of dye/silicon on the surface of uncladed fiber core. Sensor output signal represented the several hexagonal response pattern from the different output signals of the six-channel optical fiber sensor by changing each taste solution's concentration. Optical fiber taste sensor based on the evanescent field absorption provides a quantitative, objective measure of taste solutions with improved sensitivity and lower detection limits better than conventional electrode type taste sensor. This device will be useful in diverse ranges from food industry to environmental and biomedical monitoring.