Optical Behavior of Nile Red in Organic and Aqueous Media Environments

A simple model is proposed to calculate the dimerization constant of a dye in non-aqueous solvents. Alkan-1ols formula H–(CH2)n–OH are used study spectroscopic behavior Nile Red dye. The number n varied from 1 8 modulate medium hydrophobicity. Generally, red localize lipid droplets within cells. This molecule non-fluorescent water and other polar solvents but undergoes fluorescence enhancement large absorption emission blue shifts non-polar environments. calculated equilibrium constants suggest that aggregation process solvent-assisted. spectra reveal marked shift, which studied by breaking wavelength maximum band into two terms, showing contribution solvent effect concentration. Both contributions were investigated as function n, it was found alkan-1ols with tend aggregate produce smaller shift. Conversely, also noticed short-chain stabilize excited state via H-bond shift increases. hydrophilicity be modulated adding pure water, controlled way, binary systems dye–H–(CH2)n–OH (n = 1–8). quantification described ratio R moles/alcohol moles. From this investigation, we realized values strictly connected parameter. In context, allow us determine adjustable parameters.