Spectroscopic and Theoretical Studies of Fluorescence Effects in 2-Methylamino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole Induced by Molecular Aggregation

Journal Article · Mon Jan 15 04:00:00 EST 2018 · Journal of Fluorescence (Online)

DOI:https://doi.org/10.1007/S10895-017-2175-2· OSTI ID:22795688

Matwijczuk, Arkadiusz ^[1]; Górecki, Andrzej ^[2]; Makowski, Marcin; Pustuła, Katarzyna ^[3]; Skrzypek, Alicja ^[4]; Waś, Joanna ^[5]; Niewiadomy, Andrzej ^[4]; Gagoś, Mariusz ^[6]

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1. University of Life Sciences in Lublin, Department of Biophysics (Poland)
2. Jagiellonian University, Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology (Poland)
3. Jagiellonian University, Department of Theoretical Chemistry, Faculty of Chemistry (Poland)
4. University of Life Sciences in Lublin, Department of Chemistry (Poland)
5. Jagiellonian University, Departament of Chemistry (Poland)
6. Maria Curie-Skłodowska University, Department of Cell Biology, Institute of Biology (Poland)

The article presents the results of fluorescence analyses of 2-methylamino-5-(2,4-dihydroxyphenyl)-1,3,4-thiadiazole (MDFT) in an aqueous environment. MDFT dissolved in aqueous solutions with a pH value in the range from 1 to 4.5 yielded an interesting effect of two clearly separated fluorescence emissions. In turn, a single fluorescence was observed in MDFT dissolved in water solutions with a pH value from 4.5 to 12. As it was suggested in the previous investigations of other 1,3,4-thiadiazole compounds, these effects may be associated with conformational changes in the structure of the analysed molecule accompanied by aggregation effects. Crystallographic data showed that the effect of the two separated fluorescence emissions occurred in a conformation with the –OH group in the resorcyl ring bound on the side of the sulphur atom from the 1,3,4-thiadiazole ring. The hypothesis of aggregation as the mechanism involved in the change in the spectral properties at low pH is supported by the results of (Time-Dependent) Density Functional Theory calculations. The possibility of rapid analysis of conformational changes with the fluorescence spectroscopy technique may be rather important outcome obtained from the spectroscopic studies presented in this article. Additionally, the presented results seem to be highly important as they can be easily observed in solutions and biologically important samples.

• OSTI ID: 22795688
• Journal Information: Journal of Fluorescence (Online), Journal Name: Journal of Fluorescence (Online) Journal Issue: 1 Vol. 28; ISSN 1573-4994
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
AQUEOUS SOLUTIONS
ATOMS
CONFORMATIONAL CHANGES
CRYSTALLOGRAPHY
DENSITY FUNCTIONAL METHOD
FLUORESCENCE
FLUORESCENCE SPECTROSCOPY
MOLECULES
PH VALUE
SULFUR
THIADIAZOLES
TIME DEPENDENCE