TY - JOUR AU - Kudrya, V. Yu. AU - Yashchuk, V. M. AU - Naumenko, A. P. AU - Mely, Y. AU - Gumenyuk, Ya. O. PY - 2020/04/17 Y2 - 2024/03/28 TI - Low-Temperature Luminescent Studies of Emissive Guanine Substitute for the Detection of Biopolymers JF - Ukrainian Journal of Physics JA - Ukr. J. Phys. VL - 65 IS - 4 SE - Optics, atoms and molecules DO - 10.15407/ujpe65.4.317 UR - https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2019626 SP - 317 AB - <p>The optical absorption at 300 K and the fluorescence and phosphorescence at 78 K of the emissive guanine substitute, deoxythienoguanosine, (d<sup>th</sup>G) were investigated in aqueous and TRIS-HCl-buffer solutions. Two optical absorption and fluorescence centers at room temperature were attributed to two keto-enol tautomers of d<sup>th</sup>G, which confirms previously obtained results. In contrast to room temperature, only one emission band was observed at 78 K in fluorescence spectra that was close to the long-wave fluorescence band at room temperature and could be associated with the tautomer with long-wave absorption. This phenomenon can be explained by the energy transfer by excitations in a frozen solution between two types of the optical centers mentioned above. The similar conclusion is drawn for the phosphorescence: only one tautomer phosphorescence band is observed. The spectral positions of this band maximum are essentially different for aqueous and buffer solutions (∼50 nm).</p> ER -