Guralchuk G Ya, Sorokin A V, Katrunov I K, Yefimova S L, Lebedenko A N, Malyukin Yu V, Yarmoluk S M
Institute for Scintillation Materials, STC Institute for Single Crystals, NAS of Ukraine, 60 Lenin Ave., 61001 Kharkov, Ukraine.
J Fluoresc. 2007 Jul;17(4):370-6. doi: 10.1007/s10895-007-0201-5. Epub 2007 Jun 13.
Optical spectroscopy experiments were used to study the features of cyanine dye 3,3'-dimethyl-9-(2-thienyl)-thiacarbocyanine iodide (L-21) aggregation in binary solutions DMF:Tris-HCl buffer (pH = 8) containing nucleic acids (DNA or RNA). The appearance of absorption and luminescence bands associated with J-aggregates and dimers that are formed within the minor groove of DNA has been observed. The model of L-21 J-aggregate structure is proposed. It has been found that dimers are the building blocks of L-21 J-aggregates. Disorientation in dimers caused by the minor groove curvature is reason of observation of Davydov splitting in absorption spectrum of L-21 J-aggregates. In the solution containing DNA the absorption and luminescence bands of L-21 J-aggregates exhibit the specific properties that allows the dye L-21 to be used as a fluorescent probe for DNA detection.
利用光谱实验研究了花菁染料3,3'-二甲基-9-(2-噻吩基)-硫代碳菁碘化物（L-21）在含有核酸（DNA或RNA）的二元溶液N,N-二甲基甲酰胺：Tris-HCl缓冲液（pH = 8）中的聚集特性。观察到与在DNA小沟内形成的J-聚集体和二聚体相关的吸收和发光带的出现。提出了L-21 J-聚集体结构模型。已发现二聚体是L-21 J-聚集体的构建单元。由小沟曲率引起的二聚体中的取向紊乱是在L-21 J-聚集体的吸收光谱中观察到达维多夫分裂的原因。在含有DNA的溶液中，L-21 J-聚集体的吸收和发光带表现出特定性质，这使得染料L-21可作为用于DNA检测的荧光探针。
