Thermodynamic Fluctuations in a Reacting System—Measurement by Fluorescence Correlation Spectroscopy

Key Points

• To measure temporal correlations of thermodynamic concentration fluctuations in a reactive equilibrium system to simultaneously determine chemical rate constants and diffusion coefficients.
• Applied fluorescence correlation spectroscopy to detect spontaneous fluorescence fluctuations of reaction products at chemical equilibrium.
• Analyzed the equilibrium binding interaction between ethidium bromide and DNA.
• Extracted chemical rate constants and diffusion coefficients directly from the temporal correlation of equilibrium fluctuations.
• Demonstrated the experimental observation of coupling between molecular diffusion and chemical reaction kinetics.