• Journal of Photoscience
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• v.4 no.1
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• pp.1-5
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• 1997

A hitherto unknown diphenylbutadiene analog viz. 1-(p-N,N-dimethylaminophenyl)-4-phenyl-2-methyl-1E,3E-butadiene (10) has been prepared and its absorption, excitation, and fluorescent emission properties in different media including various organic solvents and aqueous bovine serum albumin (BSA) have been studied. For comparision, these properties have also been investigated for the parent diphenylbutadiene (2). Diene 10 exhibits solvent polarity/polarizability-sensitive fluorescence properties ($\lambda$$_{max}$, $\Phi$$_f$, $\tau$$_f$, K$_f$, f). It also binds to the hydrophobic domains of aqueous bovine serum albumin (BSA) with a binding constant of 3.89 x 10$^4$ M$^{-1}$. The relative fluorescence quantum yield of 10 increases, while, the fluorescence lifetime decreases with increasing concentration of-BSA. The results highlight the polar character of the singlet excited state of diphenylpolyenes and the utility of 10 as fluorescence probe for studying microenvironments of organized assemblies and biological supramolecular structures.

• Archives of Pharmacal Research
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• v.4 no.1
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• pp.19-24
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• 1981

The possibility of using a fluorescence probe technique for the study of ibuprofenlysine binding to human and bovine serum albumin was investigated. 1-anilino-8-naphalenesulfonate was used as the probe. The number of binding sites of human and bovine serum albumins for ibuprofenlysine appears to be 4 and 2, respectively. By using this technique, the association constants were found to be $1.533{\times}10^{4}M^{-1}$ and $2.238{\times}10^{4}M^{-1}$, respectively.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1086-1087
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• 2005

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.746-750
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• 2011

Fluorescence correlation spectroscopy (FCS) is an emerging fluorescence technique used to study the dynamics of proteins on a millisecond to microsecond time scale at the single-molecule level. Solution pH-modulated protein conformational changes can be manifested by binding rate, fluorescence lifetime, and binding specificity of a probe molecule. The fluorescence lifetime of Nile red (NR) bound to apomyoglobin (apoMb) was measured to be $6{\pm}0.3$ ns, much longer than that in water solution ($2.9{\pm}0.2$ ns). As the unfolding population of apoMb increased by lowering pH of solution, the fraction for the longer lifetime of NR decreased with an increasing fraction for the shorter lifetime of NR in water. Unlike 1-anilino-8-naphthalene sulfonic acid, which has many lifetimes due to nonspecific binding to the unfolded apoMb, NR bound to apoMb possesses only a single lifetime. These results suggest that NR binds specifically to native apoMb and thus can be utilized to probe the folding/unfolding dynamics of apoMb using FCS.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.77-82
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• 1992

In order to investigate the protein binding characteristics of braD6n and hematoxy6n to bovine semm albumin (BSA), the fluorescence probe method was adopted. Brazilin and hematoxy6n showed strong binding affinity for BSA. It was also confirmed that hematoxy6n was bound to BSA stronger than braDlin. The association constants were decreased by the elevation of concentrations of brazilin and hematoxylin. It might be due to the complex formation of the probe and both compounds or the interaction between the probe-protein complex and both compounds. The bindings between both compounds and BSA were dependent on pH and ionic strength. It seems that electrostatic force as weD as hydrophobic force is involved in the binding of braD6n and bematoxylin to BSA.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.389-393
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• 2013

A rhodamine B-based fluorescent probe for nitrite ion ($NO{_2}^-$) has been designed, synthesized, characterized and its properties for recognition of $NO{_2}^-$ were studied. Nearly non fluorescent probe upon reaction with nitrite ion significantly triggered the fluorescence. Fluorescence response is based on ring opening of the spirolactam of rhodamine B phenyl hydrazide showing maximum absorbance at 552 nm and maximum emission at 584 nm. Probe 3 exhibited high sensitivity and extreme selectivity for nitrite ion over other common ions and oxidants ($Cl^-$, $ClO^-$, $ClO{_2}^-$, $ClO{_3}^-$, $ClO{_4}^-$, $SO{_4}^{2-}$, $SiO{_3}^{2-}$, $NO{_3}^{2-}$, $CO{_3}^{2-}$) examined in methanol water (1:1, v/v) at pH 7.0. The probe might be a new efficient tool for detection of nitrite ion in natural water and biological system.

• Environmental Mutagens and Carcinogens
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• v.17 no.1
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• pp.12-16
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• 1997

Chromosome rearrangement induced by bleomycin were identified by fluorescence in situ hybridization with probe for chromosome 4. The frequency of color junctions, translocations, dicentric and acenttic fragments increased with bleomycin dose. Different types of balanced translocation and dicentric were scored and compared. The frequency of cells exhibiting multiple aberration was higher compared to that of cells exposed to Gamma radiation suggesting that effect of bleomycin might be similar to that of high LET radiation.

• Archives of Pharmacal Research
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• v.9 no.3
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• pp.139-144
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• 1986

The solubilization sites of aniline and its derivatives in micelles were investigated with fluorescence probe technique. The fluorescence probes employed in this study are 12-(9-anthroyl) stearic acid (AS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) which are incorporated in the interior of the micelle and attaced to its surface, respectively. As these two probes were effectively quenched by aniline and its surface, respectively. As these two probes were effectively quenched by aniline and its derivatives, the modified Stern-Volmer relationship in micellar system could be applicable to estimate the partition coefficient, $K_{p}$ of the solubilizate between aqueous and micellar phase. Because $K_{p}$ derived by this method reflects the relative proximity of the fluorophore to the quencher, the ratio of $K_{p}$ in the surface area to that in the interior of the micelle is interpreted in terms of the relative location of the solubilizate in micellar aggregate. The results show that the solubilizates are not located in a definite position but distributed in the multiple-sites of the micelle. The solubilization sites of the solubilizates in the icelle are dependent on their structures. As the solubilizate has more numbers of N-substituents of aniline and more numbers, of carbon in the substituent, it tends to incorporate in the interior of the micelle more effectively.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2256-2260
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• 2013

A new quinoline-based acylhydrazone (1) has been synthesized and applied as a fluorescent probe. Probe 1 exhibits high selectivity and sensitivity to $Cu^{2+}$ with fluorescence "ON-OFF" behavior in HEPES buffered (1‰ DMSO, HEPES 20 mM, pH = 7.4) solution. The on-site generated 1-$Cu^{2+}$ complex displays excellent selectivity to sulfide ions with fluorescence "OFF-ON" performance through copper displacement approach.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.177-181
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• 2020

Dual-modality imaging strategy using near-infrared fluorescence (FLI) and photoacoustic imaging (PAI) demands a suitable probe to enable dual-modular signal production. Herein, we demonstrate a synthetic protocol of small molecular dye for dual-modular FLI and PAI. A condensation reaction between squaric acid and carboxypentyl benzoindolium, and followed by basic hydrolysis to give the benzoindole derived squaraine (BSQ) dye in 49% yield. Next, the carboxylic acid group of BSQ was further functionalized with N-hydroxysuccinimide or azide group for an efficient conjugation with a targeting biomolecule. BSQ showed a maximum fluorescent emission at around 680 nm and the photoacoustic signal reached a maximum intensity at 680-700 nm. Based on these results, we conclude that BSQ analogs will be useful probes for dual-modular (FLI/PAI) imaging studies in animal models.