Fluorescence Spectra and Fluorescence Quantum Yield of Ferulic Acid

Fluorescence spectra and fluorescence quantum yield of ferulic acid(FA) have been studied.Under acidic conditions,fluorescence of FA aqueous solution increases along with the increase of pH,maximum excitation wavelength λex and emission wavelength λem were 310 nm and 415 nm,respectively.Under alkaline conditions,Maximum excitation and emission wavelength red shift at 350 nm and 460 nm and fluorescence decreases along with the increase of pH.When pH10.0,fluorescence reached the maxium value and did not change.The reason of the fluorescence change is because of the ionization of protons of carboxyl and hydroxyl groups in FA molecule.Taking quinine bisulphate as a reference,fluorescence quantum yield of FA aqueous solution was measured to be 0.006 1.