N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 4 Kosygin Str., 119334 Moscow, Russia.
Int J Mol Sci. 2023 Sep 11;24(18):13954. doi: 10.3390/ijms241813954.
In search of new probes for biomolecules, the spectral fluorescent study of four monomethine cyanine dyes (MCD), both unsymmetrical and symmetrical, has been carried out in different organic solvents, in aqueous buffer solutions, and in the presence of DNA and HSA. The complexation of MCD with biomacromolecules leads to a steep growth of the fluorescence intensity. Complexes of MCD with dsDNA and HSA of various types were modeled in silico by molecular docking. Experiments on thermal dissociation of dsDNA in the presence of MCD showed the formation of intercalative complexes of MCD with DNA. Quenching of intrinsic fluorescence of HSA by MCD occurred with rate constants much higher than the diffusion limit, that is, in dye-HSA complexes. Effective constants of MCD complexation with the biomacromolecules were estimated. MCD has the best characteristics as a possible fluorescent probe for dsDNA and can serve as a sensitive and selective probe for dsDNA in the presence of HSA. Photochemical properties of MCD complexed with DNA have been also studied. An increase in the quantum yield of the triplet states of MCD in complexes with DNA has been found, which may be important for using these dyes as potential candidates in photodynamic therapy.
为了寻找新的生物分子探针，我们对四种单甲川花菁染料（MCD）进行了光谱荧光研究，这些染料既有不对称的也有对称的，分别在不同的有机溶剂、水缓冲溶液以及 DNA 和 HSA 的存在下进行了研究。MCD 与生物大分子的络合导致荧光强度急剧增加。通过分子对接对 MCD 与各种类型的 dsDNA 和 HSA 的复合物进行了计算机模拟。实验表明，在 MCD 的存在下，dsDNA 的热解离形成了 MCD 与 DNA 的插入式复合物。MCD 猝灭 HSA 的内荧光发生在比扩散限制更快的速率常数下，即在染料-HSA 复合物中。估计了 MCD 与生物大分子络合的有效常数。MCD 作为 dsDNA 可能的荧光探针具有最佳特性，并且可以在存在 HSA 的情况下作为 dsDNA 的灵敏和选择性探针。还研究了与 DNA 络合的 MCD 的光化学性质。发现与 DNA 形成复合物后，MCD 的三重态量子产率增加，这对于将这些染料用作光动力治疗的潜在候选物可能很重要。
