• 한국고분자학회지:고분자과학과기술
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• 제26권1호
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• pp.9-15
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• 2015

• 분석과학
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• 제29권1호
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• pp.35-42
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• 2016

A new nano-composite carbon ink for the development of disposable dopamine (DA) biosensors based on screen-printed carbon electrodes (SPCEs) is introduced. The method developed uses SPCEs coupled with a tyrosinase modified nano-composite carbon ink. The ink was prepared by an “in-house” procedure with reduced graphene oxide (rGO), Pt nanoparticles (PtNP), and carbon materials such as carbon black and graphite. The rGO-PtNP carbon composite ink was used to print the working electrodes of the SPCEs and the reference counter electrodes were printed by using a commercial Ag/AgCl ink. After the construction of nano-composite SPCEs, tyrosinase was immobilized onto the working electrodes by using a biocompatible matrix, chitosan. The composite of nano-materials was characterized by X-ray photoelectron spectroscopy (XPS) and the performance characteristics of the sensors were evaluated by using voltammetric and amperometric techniques. The cyclic voltammetry results indicated that the sensors prepared with the rGO-PtNP-carbon composite ink revealed a significant improvement in electro-catalytic activity to DA compared with the results obtained from bare or only PtNP embedded carbon inks. Optimum experimental parameters such as pH and operating potential were evaluated and calibration curves for dopamine were constructed with the results obtained from a series of amperometric detections at −0.1 V vs. Ag/AgCl. The limit of detection was found to be 14 nM in a linear range of 10 nM to 100 µM of DA, and the sensor’s sensitivity was calculated to be 0.4 µAµM⁻¹cm⁻².

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.113-114
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• 2013

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging is a powerful technique for producing chemical images of small biomolecules (ex. metabolites, lipids, peptides) "as received" because of its high molecular specificity, high surface sensitivity, and submicron spatial resolution. In addition, matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) imaging is an essential technique for producing chemical images of large biomolecules (ex. genes and proteins). For this talk, we will show that label-free mass imaging technique can be a platform technology for biomedical studies such as early detection/diagnostics, accurate histologic diagnosis, prediction of clinical outcome, stem cell therapy, biosensors, nanomedicine and drug screening [1-7].

• 공업화학
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• 제27권2호
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• pp.145-152
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• 2016

본 연구에서는 전기화학적 바이오센서의 포도당 감지능을 높이고자 금 나노 입자가 분산된 다중벽탄소나노튜브(multi-walled carbon nanotube, MWCNTs)에 CuO를 도입하였다. 금 나노 입자로 인하여 나노 클러스터(cluster) 형상을 갖는 CuO가 합성되었으며, 이는 포도당 감지능력에 매우 큰 영향을 나타내었다. 0.1 mole의 CuO가 합성되었을 때 CuO/Au@MWCNTs 나노복합재를 전극재료로서 바이오센서는 $504.1{\mu}A\;mM^{-1}cm^{-2}$으로 가장 높은 민감도를 보여주었으며, 이 값은 MWCNTs만을 전극으로 이용할 때보다 약 4배 정도 컸다. 또한, 0-10 mM의 긴 선형 구간(linear range)과 0.008 mM의 낮은 LoD (limit of detection) 값을 보여주었다. 이러한 실험 결과들은 CuO/Au@MWCNTs 나노복합재가 CuO를 이용한 다른 전기화학적 바이오센서보다 우수하다는 것을 입증하였으며, 이는 나노 클러스터 형상의 CuO가 포도당 감지에서 전기화학적 반응에 유리하기 때문으로 사료된다.

• Interaction and multiscale mechanics
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• 제3권2호
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• pp.111-121
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• 2010

Dynamic analysis of nano/micro bio-sensors based on a multiscale atomistic/continuum theory is introduced. We use a generalized atomistic finite element method (GAFEM) to analyze a bio-sensor which has $3{\times}N_a{\times}N_p$ degrees of freedom, where $N_p$ is the number of representative unit cells and $N_a$ is the number of atoms per unit cell. The stiffness matrix is derived from interatomic potential between pairs of atoms. This work contains two studies: (1) the resonance analysis of nano bio-sensors with different amount of target analyte and (2) the dependence of resonance frequency on finite element mesh. We also examine the Courant-Friedrichs-Lewy (CFL) condition based on the highest resonance frequency. The CFL condition is the criterion for the time step used in the dynamic analysis by GAFEM. Our studies can be utilized to predict the performance of micro/nano bio-sensors from atomistic perspective.

• 폴리머
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• 제29권6호
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• pp.613-616
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• 2005

본 연구에서는 한 개의 세포와 같은 미세한 생체시료 내부의 분석 대상물질을 감지하는데 사용할 수 있는 광바이오센서를 개발하기 위한 첫 단계로서 효소가 함유된 고분자 수화젤 구형입자를 나노크기로 중합하는 방법을 확립하고 센서로서의 사용 가능성을 확인하였다. 현탁 광중합을 통하여 305 nm의 평균크기를 가지는 horseradish peroxidase(HRP)가 함유된poly(ethylene glycol)(PEG) 수화젤 구형입자를 합성하였으며, 중합반응 이후 입자내부의 효소의 존재 및 활성유지를 HRP와$\H_{2}O_{2}$의 효소반응에 의한 Amplex Red의 형광산화물 생성을 통하여 확인하였다. 합성된 HRP가 함유된 PEG 수화젤 입자는 Amplex Red의 존재하에 $\H_{2}O_{2}$의 농도가 0에서 11 nM로 미량 변화함에 따라서 형광세기가 약 300$\%$ 증가함을 보여 주었다. 이러한 결과는 효소가 함유된 PEG 수화젤 나노입자를 합성하는 본 기술이 향후 미세한 생체시료 내부의 다양한 분석대상물질을 감지할 수 있는 나노크기의 광바이오센서를 개발하는데 이용 될 수 있는 가능성을 보여준다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.378.2-378.2
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• 2016

Biosensors currently suffer from severe non-specific adsorption of proteins, which causes false positive errors in detection through overestimation of the affinity value. Overcoming this technical issue motivates our research. Polyethylene glycol (PEG) is well known for its ability to reduce the adsorption of biomolecules; hence, it is widely used in various areas of medicine and other biological fields. Likewise, amine functionalized surfaces are widely used for biochemical analysis, drug delivery, medical diagnostics and high throughput screening such as biochips. As a result, many coating techniques have been introduced, one of which is plasma polymerization - a powerful coating method due to its uniformity, homogeneity, mechanical and chemical stability, and excellent adhesion to any substrate. In our previous works, we successfully fabricated plasmapolymerized PEG (PP-PEG) films [1] and amine functionalized films [2] using the plasma enhanced chemical vapor deposition (PECVD) technique. In this research, an amine functionalized PP-PEG film was fabricated by using the plasma co-polymerization technique with PEG 200 and ethylenediamine (EDA) as co-precursors. A biocompatible amine functionalized film was surface characterized by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR). The density of the surface amine functional groups was carried out by quantitative analysis using UV-visible spectroscopy. We found through surface plasmon resonance (SPR) analysis that non-specific protein adsorption was drastically reduced on amine functionalized PP-PEG films. Our functionalized PP-PEG films show considerable potential for biotechnological applications such as biosensors.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.290-293
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• 2009

This paper presents the development of a disposable label-free biosensor for bio molecular interaction analysis. Label-free biosensors have advantages of high performance in sensitivity and short detection time. Among various label-free systems, we introduced biosensor with nano grating structures based on white light source and spectrometer. And to develop high efficiency label-free biosensor, we suggest replicating processes satisfying required specification. We also report a system set-up to evaluate the characteristics of phenomenon shown in this biosensor system.

• 전자공학회지
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• 제31권1호
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• pp.58-72
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• 2004

Smart sensors and biochip technologies have received a great deal of attention in recent years not only because of the enormous potential markets in the healthcare expenditures but more importantly because of its great impact on the quality of human life in the future. Collaborative research among BT (Bio Technologies), IT (Information Technologies) and NT (Nano Technologies) will bring us a new paradigm of the healthcare services. Examples include disease prediction based on the genetic tests, personal medicines, point-of-care analysis, rapid and sensitive infectious disease diagnostics, environmental monitoring for chemical or biological warfares, intelligent drug delivery systems etc. In this report, recent accomplishment in the research area on biosensors, DNA chips, Protein Chips and Lab-on-a-chips are reviewed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1094-1099
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• 2003

Nanometer-sized structures are being applied to many fields including micro/nano electronics, optoelectronics, quantum computing, biosensors, etc. Multi-scale analysis technology is required for designing the reliable nanometer-sized structures and predicting their mechanical, chemical and electronic behaviors. In this paper, some techniques for multi-scale analysis are reviewed and their applicability and limitation are discussed. Research activity of nano process analysis team in KIMM is outlined. Especially, we concentrate on OCTA of Nagoya University in Japan for the analysis of polymeric materials. Detailed structure of OCTA is described and some examples are presented.