Photophysical Properties of Fluorescent Probe Thioflavin T in Crowded Milieu

Figure 2

Absorption, fluorescence, and fluorescence excitation spectra of ThT in aqueous solutions in the presence of crowding agents and glycerol. (a) Absorption and fluorescence spectra (solid lines) of ThT in aqueous solutions in the presence of Dextran-70 in concentrations 0, 10, 50, 100, 150, 200, 250, 300, and 400 mg/mL (curves 1–9) and fluorescence excitation spectra (dashed lines) of ThT in aqueous solutions in the presence of Dextran-70 in concentrations 0, 10, 100, and 400 mg/mL (colors are similar to that of the absorption and fluorescence spectra) are presented. (b) Absorption and fluorescence spectra (solid lines) of ThT in aqueous solutions in the presence of PEG-400 in concentrations 0, 100, 200, 300, and 400 mg/mL (curves 1–5) and fluorescence excitation spectra (dashed lines) of ThT in aqueous solutions in the presence of PEG-400 in concentrations 0, 200, 300, and 400 mg/mL (colors are similar to that of the absorption and fluorescence spectra) are presented. (c) Absorption and fluorescence spectra (solid lines) of ThT in aqueous solutions in the presence of PEG-12000 in concentrations 0, 10, 20, 50, 100, 150, 200, 250, 300, 350, and 400 mg/mL (curves 1–11) and fluorescence excitation spectra (dashed lines) of ThT in aqueous solutions in the presence of PEG-12000 in concentrations 0, 10, 100, and 300 mg/mL (colors are similar to that of the absorption and fluorescence spectra) are presented. (d) Absorption and fluorescence spectra (solid lines) of ThT in aqueous-glycerol solutions with glycerol content of 0, 12, 25, 46, 61, 75, 89, and 99% (curves 1–8) and fluorescence excitation spectra (dashed lines) of ThT in aqueous-glycerol solutions with glycerol content of 0, 12, 61, and 89% (colors are similar to that of the absorption and fluorescence spectra) are presented; ThT concentration was ~3⋅10⁻⁵ M. Fluorescence spectra were excited at 412 nm and recorded at 490 nm.

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