• Genomics & Informatics
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• 제5권3호
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• pp.113-117
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• 2007

The development of microarray technology has facilitated the understanding of gene expression profiles. Despite its convenience, the cause of dye-bias that confounds data interpretation in dual-color DNA microarray experiments is not well known. In order to economize time and money, it is necessary to identify the cause of dye bias, since designing dye-swaps to reduce the dye-specific bias tends to be very expensive. Hence, we sought to determine the reliable cause of systematic dye bias after treating murine macrophage RAW 264.7 cells with 2-keto-3-deoxyoctonate (KDO), interferon-beta $(IFN-{\beta})$, and 8-bromoadenosine (8-BR). To find the cause of systematic dye bias from the point of view of fluorescence quenching, we examined the correlation between systematic dye bias and the proportion of each nucleotide in mRNA and oligonucleotide probe sequence. Cy3-dye bias was highly correlated with the proportion of adenines. Our results support the fact that systematic dye bias is affected by fluorescence quenching of each feature. In addition, we also found that the strength of fluorescence quenching is based on not only dye-dye interactions but also dye-nucleotide interactions as well.

• 대한소아치과학회지
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• 제31권2호
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• pp.323-330
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• 2004

본 연구는 레이저 형광을 치아의 인접면에 적용하여 임상에서 초기 인접면 우식증의 감별에 레이저의 이용가능성을 평가하는데 그 목적이 있다. 염료와 레이저 형광법의 인접면 우식증 탐지효과를 평가하기 위해 조선대학교 소아치과에 내원한 아동 중 유구치의 탈락이 없으며 인접면의 수복치료를 받지 않은 $3{\sim}9$세 사이의 어린이 30명을 대상으로 하였으며, 시진, 교익 방사선사진, 레이저 형광법, 염료와 레이저 형광법을 이용해 관찰한 결과를 비교하여 다음과 같은 결과를 얻었다. 1. 인접면 우식증의 교익 방사선 사진검사와 시진, 레이저 형광법, 염료와 레이저 형광법 사이에서 모두 높은 상관 관계(r=0.725-0.911)를 보였다(p<0.05). 2. 인접면 우식증의 교익 방사선사진 검사와 각 검사법간의 일치도(kappa치)는 각각 시진이 0.451 레이저 형광법이 0.683, 염료와 레이저 형광법이 0.772로 가장 일치도가 높았다. 이상의 결과를 종합해 보면 교익 방사선사진 검사법과 염료와 레이저 형광법 검사 수치의 상관관계가 진단학적 일치도가 높아 레이저 형광법이 향후 교익방사선 사진 검사법을 대치 할 수 있는 인접면 우식증 검사법으로 사료된다.

• 한국염색가공학회지
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• 제29권4호
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• pp.223-230
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• 2017

Three super hydrophobic fluorescence dyes were selected to dye high molecular weight polyethylene fiber and their molar absorptivity, emission spectrum, and quantum yield were measured. From the results of color strength on the fiber, all the three dyes exhibited linear increase according to the dye concentration and Fluoro3 dye showed the highest color strength among them. Emission strength of the fluorescence dyes on the fiber was investigated according to the dye concentrations. The emission was increased with the increase of the dye concentration at relatively low dye concentration and then after showing the maximum emission strength the emission was decreased at higher dye concentrations. The highest emission was obtained in Fluoro2 dye. Color fastness to washing and rubbing was generally good enough, however, especially to light, only Fluoro3 dye exhibited rating 3 acceptable practically and Fluoro1 and 2 was ratings 1 which is unacceptable level.

• Journal of the Optical Society of Korea
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• 제12권2호
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• pp.107-111
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• 2008

We demonstrated single-molecule fluorescence resonance energy transfer (FRET) from single donor-acceptor dye pair attached to a DNA with a setup based on a confocal microscope. Singlestrand DNAs were immobilized on a glass surface with suitable inter-dye distance. Energy transfer efficiency between the donor and the acceptor dyes attached to the DNA was measured with different lengths of DNA. Photobleaching of single dye molecule was observed and used as a sign of single-molecule detection. We could achieve high enough signal-to-noise ratio to detect the fluorescence from a single-molecule, which allows real-time observation of the distance change between single dye pairs in nanometer scale.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.88.2-88.2
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• 2010

Dye-sensitized solar cells (DSSCs) have attracted considerable attention on account of their high solar energy-to-conversion efficiencies and low cost processes compared to conventional p-n junction solar cells. The mechanism of DSSC is based on the injection of electrons from the photo excited dyes into the conduction band of the semiconductor electrode. The oxidized dye is reduced by the hole injection into either the hole conductor or the electrolyte. Thus, the light harvesting effect of dye plays an important role in capturing the photons and generating the electron/hole pair, as well as transferring them to the interface of the semiconductor and the electrolyte, respectively. We used the organic fluorescence materials which can absorb short wavelength light and emit longer wavelength region where dye sensitize effectively. In this work, the DSSCs were fabricated with fluorescence materials added $TiO_2$ photo-electrode which were sensitized with metal-free organic dyes. The photovoltaic performances of fluorescence aided DSSCs were compared, and the recombination dark current curves and the incident photon-to-current (IPCE) efficiencies were measured in order to characterize the effects of the additional light harvesting effect in DSSC. Electro-optical measurements were also used to optimize the fluorescence material contents on TiO2 photo-electrode surface for higher conversion efficiency (${\eta}$), fill factor (FF), open-circuit voltage (VOC) and short-circuit current (ISC). The enhanced light harvesting effect by the judicious choice/design of the fluorescence materials and sensitizing dyes permits the enhancement of photovoltaic performance of DSSC.

• 대한소아치과학회지
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• 제31권2호
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• pp.236-246
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• 2004

레이저 형광법을 이용하여 초기 인접면 우식증을 탐지할 수 있는지의 여부와 그 탐지 감도를 평가하여 인접면 우식증의 진단에 활용가능한지의 여부를 규명하기 위하여 사람의 치아를 사용하여 다양한 깊이의 인공우식병소를 유발시키고 이를 가시광선 투과법에 의한 시진, 교익 방사선사진 촬영, 레이저 형광법, 광활성 염료를 이용한 레이저 형광법 등으로 관찰하여 검사법 간의 일치도, 상관관계, 병소 깊이에 따른 광밀도 등을 분석하여 다음과 같은 결과를 얻었다. 1. 탈회시간과 각 검사법들과 일치도 검사에서 시진의 경우 tau-c 값이 0.08로 탈회시간에 따른 시진의 검사 수치가 일치하지 않았으나 교익 방사선사진, 레이저 형광법, 광활성 염료를 이용한 레이저 형광법의 tau-c 값은 각각 0.60, 0.48, 0,64로 일치하는 것으로 나타났다. 2. 탈회시간에 따른 병소깊이와 각 검사법 간의 상관관계는 광활성 염료를 이용한 레이저 형광법$({\gamma}=0.51)$, 레이저 형광 법$({\gamma}=0.43)$, 교익 방사선사진$({\gamma}=0.35)$, 시진$({\gamma}=0.33)$ 순으로 높았으며 광활성 염료를 이용한 레이저 형광법과 레이저 형광법은 탈회 시간과 상관관계가 있었다(P<0.05). 3. 교익 방사선사진을 기준 검사법으로 한 레이저 형광법과 광활성 염료를 이용한 레이저 형광법의 진단학적 민감도는 각각 67%, 100%였으며 특이도는 57%, 11%로 민감도에 비해 상대적으로 낮게 나타났다. 4. 병소의 깊이에 따른 병소 표면에서의 건전 치질과 우식 치질 사이의 광밀도의 차이(DFR)는 광활성 염료를 이용한 레이저 형광법이 레이저 형광법에 비해 크게 나타났으며(P<0.05) 병소 깊이의 변화에 따른 광밀도 변화는 레이저 형광법의 경우 유의한 변화를 보이는데 반해 광활성 염료를 이용한 레이저 형광법에서는 변화를 보이지 않았다. 이상의 결과를 종합하면 초기 인접면 우식증의 진단에 있어 레이저 형광법과 광활성 염료를 이용한 레이저 형광법은 교익 방사선사진에 뒤지지 않은 진단능을 가지고 있으나 우식 병소의 정성적인 분석뿐 아니라 정량적 분석이 가능한지의 여부는 향후 더 많은 연구가 필요하리라 사료된다.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.3998-4002
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• 2012

With continuing progress of nanotechnologies and various applications of nanoparticles, one needs to develop a quick and fairly standard assessment tool to evaluate cytotoxicity of nanoparticles. However, much cytotoxicity studies on the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Here, we propose a simple screening method for the analysis of the interaction between several AgNPs (5.3 to 64 nm) and fluorescence-dye containing vesicles ($12{\mu}m$) acting as a biomimetic cell-membrane. Fluorescence-dye containing vesicle was prepared using a fluorescence probe (1,6-diphenyl-1,3,5-hexatryene), which was intercalated into the lipid bilayer due to their hydrophobicity. Zeta potential of all materials except for bare-AgNPs (+32.8 mV) was negative (-26 to -54 mV). The morphological change (i.e., rupture and fusion of vesicle, and release of dye) after mixing of the vesicle and AgNPs was observed by fluorescence microscopy, and fluorescence image were different with coating materials and surface charge of x-AgNPs. In the results, we found that the surface charge of nanoparticles is the key factor for vesicle rupture and fusion. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• 대한화학회지
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• 제38권12호
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• pp.857-863
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• 1994

Sodium dodecyl sulfate (SDS) 존재하에서 유기색소인 thionine (TH)의 흡수 및 형광분광학적 성질을 조사 연구하였다. SDS 농도 증가에 따라 측정한 흡수 및 형광스펙트럼의 변화들로부터 i) TH-SDS 착화합물의 회합체 형성, ii)TH-SDS 회합체내의 색소분자의 stacking 과정, iii)dye-rich induced micelles의 형성에 의한 staking의 파괴 및 iv) SDS 미셀의 표면에 TH의 재분포과정 등으로 설명하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.117.1-117.1
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• 2011

We have demonstrated Forst-type resonance energy transfer (FRET) in the quasi-solid type dye-sensitized solar cells between organic fluorescence materials as an energy donor doped in polymeric gel electrolyte and ruthenium complex as an energy acceptor on surface of $TiO_2$. The strong spectral overlap of emission/absorption of energy donor and acceptor is required to get high FRET efficiency. The judicious choice of energy donor allows the enhancement of light harvesting characters of energy acceptor in quasi-solid dye sensitized solar cells which increase the power conversion efficiency. The enhanced light harvesting effect by the judicious choice/design of the fluorescence materials and sensitizing dyes permits the enhancement of photovoltaic performance of DSSC.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2937-2941
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• 2013

Fluorescence imaging is considered as one of the most powerful techniques for monitoring biomolecule activities in living systems. Near-infrared (NIR) light is advantageous for minimum photodamage, deep tissue penetration, and minimum background autofluorescence interference. Herein, we have developed a new NIR fluorescent dye, namely, RB-1, based on the Rhodamine B scaffold. RB-1 exhibits excellent photophysical properties including large absorption extinction coefficients, high fluorescence quantum yields, and high photostability. In particular, RB-1 displays both absorption and emission in the NIR region of the "biological window" (650-900 nm) for imaging in biological samples. RB-1 shows absorption maximum at 614 nm (500-725 nm) and emission maximum at 712 nm (650-825 nm) in ethanol, which is superior to those of traditional rhodamine B in the selected spectral region. Furthermore, applications of RB-1 for fluorescence imaging in living cells and small animals were investigated using confocal fluorescence microscopy and in vivo imaging system with a high signal-to-noise ratio (SNR = 10.1).