• Interdisciplinary Bio Central
• /
• v.4 no.2
• /
• pp.5.1-5.9
• /
• 2012

Small peptide tags such as c-myc, HA, or FLAG tag have facilitated efficient Western-blotting of proteins of interest especially when specific antibodies for the proteins are not available. However, the conventional Western-blotting requires the multi-steps process taking at least several hours up to two days. With examples of various applications, here we show a convenient and time-saving method for protein detection which employs a fluorescent chemical BDED and its binding peptide RC-tag. And we propose "Estern staining", as a standard term for protein detection method using fluorescent chemicals and their binding small peptide tags. Eastern staining may substitutes for the time-consuming "immuno-staining" in many versatile applications.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.12
• /
• pp.3437-3442
• /
• 2014

A well-known carbazole-based precursor (probe 1) was used for the detection of cysteine/homocysteine and fluoride. Probe 1 shows a "turn-on" response to cysteine/homocysteine and fluoride via enhancement in emission intensity at 442 nm and 462 nm respectively, in solutions and living cells. Furthermore, probe 1 behaves as a fluorescent molecular switch between cysteine/homocysteine and fluoride as the chemical inputs, which have been used for the development of a combinatorial logic circuit and a molecular keypad lock.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1719-1721
• /
• 2003

In this paper, electrical characteristics of inductively coupled plasma in an electrodeless fluorescent lamp were investigated using a Langmuir probe with a variation of Ar gas pressure. The RF output was applied in the range of 5-50W at 13.56MHz. The internal plasma voltage of the chamber and the probe current were measured while varying the supply voltage to the Langmuir probe in the range of -100V ${\sim}$ +100V. When the pressure of Ar gas was increased, electric current was decreased. There was a significant electric current increase when the applied RF power was increased from 10 W to 30 W. This implies that this method can be used to find an optimal RF power for efficient light illumination in an electrodeless fluorescent lamp.

• Applied Biological Chemistry
• /
• v.25 no.4
• /
• pp.224-231
• /
• 1982

${\alpha}-Tocopherol$ was found to be a fluorescent probe in determination of the phasetransition temperature of liposome. Since this was a discovery of a new aspect of ${\alpha}-tocopherol$ as an important biochemical molecule, its molecular spectroscopic characterization was carried out in order to obtain some informations on its spectral and, structural properties in various media, anticipating that the compound may entertain a wide applications in biochemical systems as a spectroscopic probe. Two species of α${\alpha}-tocopherol$, monomer and dimer, were found to exist in organic media, especially in solvents of nonhydrogen bonding ability. Monomer with maximum UV-absorption around $(291{\sim}294nm)$ is highly fluorescent, while dimer which is formed by intermolecular hydrogen bonds and absorbes with spectral peak at 298nm is nonfluorescent. ${\alpha}-tocopherol$ incorporated to liposome exhibits emission property quite different from that in various organic media showing broad and red-shifted fluorescence excitation and emission spectra. This spectral abnormality is to be interpreted to arise from chromanolate-type ion, H-dissociated ${\alpha}-tocopherol$.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.5
• /
• pp.943-947
• /
• 2008

A phosphate-specific and fluorescent probe was prepared for label-free phosphatase assays based on fluorescence polarization. By using the probe, dephosphorylation reactions of DNA and protein substrates by calf intestinal alkaline phosphatase (CIP) could effectively be monitored in real-time. Since this assay method does not require additional materials such as labeled substrates and phosphospecific antibodies to obtain fluorescence polarization signals, it is simple, cost-effective, and expected to be useful not only for measuring activity of phosphatases but also for high-throughput screening of phosphatase inhibitors.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.11
• /
• pp.3696-3700
• /
• 2012

The colorimetric and fluorescent cyanide recognition properties of 2-[(9-ethyl-9H-carbazol-3-yl)methylene]-propanedinitrile (1) in $CH_3CN-H_2O$ (2/1, v/v, HEPES 10 mM, pH = 7.0) solution were evaluated. The optical recognition process of probe 1 exhibited high sensitivity and selectivity to cyanide ion with the detection limit of $2.04{\times}10^{-6}$ M and barely interfered by other coexisting anions. The sensing mechanism of probe 1 is speculated to undergo a nucleophilic addition of cyanide to dicyanovinyl group present in compound 1. The colorimetric and fluorescent dual-modal response to cyanide makes probe 1 has a potential utility in cyanide detection.

• Proceedings of the KIEE Conference
• /
• 2004.11a
• /
• pp.150-152
• /
• 2004

In recent, there have been several developments in lamp technology that promise savings in electrical power consumption and improved quality of the lighting space. The electrodeless fluorescent lamp is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. In this paper, electron temperature and electron density were measured in a radio-frequency inductively coupled plasma using a Langmuir probe method for emission characteristics. Measurement was conducted in an Ne discharge for pressure from 10 [mTorr] and input RF power 100 [W] to 150 [W]. As for the electron density, a electron temperature was more distinguished for a emission characteristic. The results of ideal may contribute to systematic understanding of a electrodeless fluorescent lamps of emission characteristics.

• Proceedings of the KIEE Conference
• /
• 2004.11a
• /
• pp.167-170
• /
• 2004

In recent, there have been several developments in lamp technology that promise savings in electrical power consumption and improved quality of the lighting space. The electrodeless fluorescent lamp is intended as a high efficacy replacement for the incandescent reflector lamp in many applications. In this paper, electron temperature and electron density were measured in a radio-frequency inductively coupled plasma using a Langmuir probe method for emission characteristics. Measurement was conducted in an Argon, Ne discharge for pressure from 1 [mTorr] and input RF power 10 [W] to 150 [W]. As for the electron density, a electron temperature was more distinguished for a emission characteristic. The results of ideal may contribute to systematic understanding of a electrodeless fluorescent lamps of emission characteristics.

• Current Applied Physics
• /
• v.18 no.11
• /
• pp.1255-1260
• /
• 2018

In this work, a green and simple one-pot route was developed for the synthesis of highly fluorescent aminofunctionalized graphene quantum dots (a-GQDs) via hydrothermal process without any further modification or surface passivation. We synthesized the a-GQDs using glucose as the carbon source and ammonium as a functionalizing agent without the use of a strong acid, oxidant, or other toxic chemical reagent. The as-obtained aGQDs have a uniform size of 3-4 nm, high contents of amino groups, and show a bright green emission with high quantum yield of 32.8%. Furthermore, the a-GQDs show effective fluorescence quenching for $Cu^{2+}$ ions which can serve as effective fluorescent probe for the detection of $Cu^{2+}$. The fluorescent probe using the obtained aGQDs exhibits high sensitivity and selectivity toward $Cu^{2+}$ with the limit of detection as low as 5.6 nM. The mechanism of the $Cu^{2+}$ induced fluorescence quenching of a-GQDs can be attributed to the electron transfer by the formation of metal complex between $Cu^{2+}$ and the amino groups on the surface of a-GQDs. These results suggest great potential for the simple and green synthesis of functionalized GQDs and a practical sensing platform for $Cu^{2+}$ detection in environmental and biological applications.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.665-666
• /
• 2007