Influence of the N-alkyl chain length on the J-aggregation behavior of a cyanine dye

A new series of benzimidocarbocyanine dyes having diffeerent N-alkyl chain lengths (C₂–C₁₂) but the same chromophoric system was synthesized to investigate the effect of the dye structure on the photophysical properties of J-aggregate-forming dyes. For these dyes, the number of J-absorption band depends on the chain length of the alkyl substiuents, whereas the fluorescence emission spectra exhibit only a single J-band. Furthermore, an increase in the N-alkyl-chain length leads to a strong decrease in the bandwidth of the J-absorption and emission bands.     

一种菁染料－聚合物薄膜的光存存储性能

用旋涂法制备了一种菁染料－聚合物薄膜，并研究了该染料－聚合物薄膜的光谱性质和光存储性能。该染料薄膜在６６０～８３０ｎｍ波段有较强的吸收和２０％以上的反射率。在最佳实验条件下，获得了５８ｄＢ的信噪比。信噪比（ＣＮＲ）、载波信号强度（Ｃ）和薄膜反射率变化（ΔＲ）的对数（ｌｇΔＲ）成正比     

Nonradiative Relaxation of Thiacarbocyanine Dyes in Binary Mixtures

It was found that preferential solvation of cyanine dyes in binary mixtures can strongly affect both their isomerization and aggregation; the comparison of absorption and fluorescence excitation spectra might be a useful tool for studying these nonradiative processes.     

不同取代基的噻碳菁和吲哚碳菁染料对其在溴化银微晶上吸附能力及形成J-聚集体尺寸分布的影响

本文研究了5-位不同取代基的噻碳菁和吲哚碳菁染料对其在立方型颗粒和T-颗粒溴化银微晶上吸附能力的影响,并采用ACFEM(Analytical Color Fluore scence Electron Microscopy)研究了上述结构染料对其吸附在溴化银微晶所形成的J-聚集体尺寸分布的影响。实验结果表明,对吲哚碳菁染料来说,立方体溴化银微晶表面的吸附能力较T-颗粒溴化银微晶表面的吸附能力强;但对噻碳菁染料来说则相反,它们在T-颗粒溴化银微晶表面的吸附能力较立方体溴化银微晶表面的吸附能力强。另外,对5-位不同取代基的噻碳菁染料而言,无论是在立方型颗粒或T-颗粒溴化银微晶上的吸附能力来说,含取代基(无论4-取代基是吸电子型还是推电子型)的噻碳菁染料较未取代的噻碳菁染料强;而5-位取代基是吸电子型的噻碳菁染料更有利于其吸附在T-颗粒溴化银微晶表面。此外,本文还进一步证明了溴化银微晶表面上染料J-聚集体的生长过程是符合奥斯瓦尔特成熟过程的。吲哚碳菁染料在T-颗粒溴化银微晶上形成的J-聚集体的平均尺寸明显大于在立方体溴化银微晶上形成的J-聚集体的平均尺寸。吸附在立方体溴化银微晶上的5-不同取代基的噻碳菁染料对其形成J-聚集体尺寸分布的影响的研究结果表明,含取代基(-CH₃,-Ph,-Cl)的噻碳菁染料形成的J-聚集体的尺寸分布几乎相同,但与未取代的噻碳菁染料形成的J-聚集体的尺寸分布明显不同;5-位含取代基的噻碳菁染料形成的J-聚集体平均尺寸大于未取代的噻碳菁染料的。     

多甲川键菁染料光氧化机理研究

本文利用紫外-可见吸收光谱法、顺磁共振(ESR)法系统地研究了多甲川键菁染料光氧化反应机理,结果表明,单线态氧(¹O₂)、超氧阴离子(O₂^-·是导致染料光褪色的主要因素,而在没有氧气存在下,Dye^-·也促使染料光褪色。     

Optimizing Film Design and Application for the Recordable Compact Disk Developed by Two Cyanine Dye Samples

Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ａｃｙａｎｉｎｅｄｙｅｗａｓｓｔｕｄｉｅｄａｎｄｕｓｅｄａｓｌａｓｅｒｄｙｅａｎｄｐｈｏｔｏｓｅｎｓｉｔｉｚｅｒｌｏｎｇａｇｏ．Ｉｎｔｈｅｃｕｒｒｅｎｔｙｅａｒｓ,ｃｙａｎｉｎｅｄｙｅｐｒｅｐａｒａｔｉｏｎｓａｒｅｓｔｕｄｉｅｄｄｅｅｐｌｙａｎｄｗｉｄｅｌｙｕｓｅｄａｓｏｐｔｉｃａｌｓｔｏｒａｇｅｍｅｄｉａ［１］．Ｃｙａｎｉｎｅｄｙｅｈａｓａｇｏｏｄｓｏｌｕｂｉｌｉｔｙｉｎｓｏｍｅｏｒｇａｎｉｃｓｏｌｖｅｎｔｓ,ｔｈｅｒｅｆｏｒｅ,ｐｒｅｐａｒａｔｉｏｎｏｆｃｙａｎｉ…     

新型不对称五甲川菁染料的合成及光稳定性能研究

合成并表征了5种不对称五甲川菁染料,染料在甲醇中的最大吸收和荧光光谱在646—666nm之间.光降解实验证明两端取代基结构呈不对称的染料,其光稳定性明显高于两端取代基结构对称的染料.染料荧光光谱和pH值的关系表明,染料中引入苯环取代基可以增强染料在酸性或碱性溶液中的稳定性.     

Photophysical properties of fluorescent imaging biological probes of nucleic acids: SAC-CI and TD-DFT Study

Recently, exciton-controlled hybridization-sensitive fluorescent oligonucleotide (ECHO) probe, which shows strong emission in the near-infrared region via hybridization to the target DNA and/or RNA strand, has been developed. In this work, photophysical properties of the chromophores of these probes and the fluorescent mechanism have been investigated by the SAC-CI and TD-DFT calculations. Three fluorescent cyanine chromophores whose excitation is challenging for TD-DFT methods, have been examined regarding the photo-absorption and emission spectra. The SAC-CI method well reproduces the experimental values with respect to transition energies, while the quantitative prediction by TD-DFT calculations is difficult for these chromophores. Some stable structures of H-aggregate system were computationally located and two of the configurations were examined for the photo-absorption. The present results support for the assumption based on experimental measurement in which strong fluorescence is due to the monomer unit in nearly planar structure and its suppression of probes is to the H-aggregates of two exciton units. Stokes shifts of these three chromophores were qualitatively reproduced by the theoretical calculations, while the energy splitting due to H-aggregate in the hybridized probe was slightly overestimated. © 2018 Wiley Periodicals, Inc.     

SERS active Ag nanoparticles in mesoporous silicon: detection of organic molecules and peptide–antibody assays

Ag nanoparticles synthesized on porous silicon samples were studied and applied as substrates for surface‐enhanced Raman scattering (SERS). The metallic nanostructures prepared by immersion plating were characterized by UV–Vis reflectance spectroscopy and scanning electron microscopy. SERS activity of the substrates was tested using Cyanine dye 1,3,3,1′,3′,3′‐esamethyl‐5,5′‐dimethoxyindodicarbocyanine iodide (Cy5‐OCH₃) as a probe molecule. The Raman spectra obtained for different excitation wavelengths indicate amplifications ascribed to plasmonic resonances with an enhancement factor up to 10⁷. CGIYRLRS peptides were chemisorbed on the Ag nanoparticles with the plasmonic resonance tuned at the excitation energy. Such oligopeptides were used as baits for a specific polyclonal antibody. The overall Raman enhancement allowed to evidence a good selectivity to the target analyte as required by most of the SERS applications on biological assays. Copyright © 2011 John Wiley & Sons, Ltd.