Сибирский федеральный университет

Тип публикации: статья из журнала

Год издания: 2023

Идентификатор DOI: 10.3390/mi14071442

Аннотация: <jats:p>In this work, we considered the influence of viscogenic agents (glycerol, sucrose) as well as the temperature on the fluorescent characteristics of fluorescein at pH 6.5 in order to describe the acid-base status of local environment in terms of a spectrally detectable dianion-anion equilibrium. The protolytic equilibrium of fluorescein was found to depend on the solvent viscosity in a complex way. Whereas in the presence of sucrose the ratiometric signal of fluorescein (I488/I435) remains rather unchanged, the addition of glycerol (up to 40% w/w) results in the increase of the signal (up to 19%), that can be attributed to the different mechanisms of cosolvents effects on dye molecules in the ground state. Molecular dynamics of the dye in the presence of glycerol and sucrose revealed that the cosolvents preferentially interact with fluorescein monoanion and dianion, displacing water molecules from the local environment which in turn reduces the average number of the hydrogen bonds between xanthene ring of the dye and water molecules. The ratiometric signal demonstrates linear growth with the temperature in the range of 10–80 °C regardless of the presence of viscogenic agents. A linear correlation between the temperature sensitivity of the ratiometric signal and the change in the molar enthalpy of the proton dissociation reaction in buffer and viscous media was determined.</jats:p>

Журнал: Micromachines

Выпуск журнала: Т.14, №7

Номера страниц: 1442

ISSN журнала: 2072666X

• Surzhikova Darya P. (Institute of Engineering Physics and Radioelectronics, Siberian Federal University, 660041 Krasnoyarsk, Russia)
• Sukovatyi Lev A. (Biophysics Department, Siberian Federal University, 660041 Krasnoyarsk, Russia)
• Nemtseva Elena V. (Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, 660036 Krasnoyarsk, Russia)
• Esimbekova Elena N. (Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, 660036 Krasnoyarsk, Russia)
• Slyusareva Evgenia A. (Institute of Engineering Physics and Radioelectronics, Siberian Federal University, 660041 Krasnoyarsk, Russia)

• Ядро РИНЦ (eLIBRARY.RU)