[Study on saltation of fluorescence excitation spectra of erythrosine]

The fluorescence excitation spectra and absorption spectra of six kinds of erythrosine solutions with concentrations of 10, 20, 30, 40, 50 and 60 microg x mL(-1) were experimentally measured. It was found that the fluorescence excitation peaks are both located at 530 nm significantly when the concentrations of erythrosine solutions are 10 and 20 microg x mL(-1). However, the linetype saltation of fluorescence excitation spectrum occurs as the concentration of erythrosine solution is above 30 microg x mL(-1). The valley is located at 530 nm and two new peaks appear at both flanks of the valley. Compared with fluorescence excitation spectra, the absorption spectra of erythrosine solutions are without saltation and the peaks are all located at 530 nm. According to calculations and a series of contrast experiments, it was demonstrated that the absorption characteristic of erythrosine and the spectral measurement mode conspire to cause the saltation of fluorescence excitation spectra. The results can provide guidance for further research on physical and chemical properties of erythrosine, and offer help and reference for study on saltation behavior in fluorescence excitation spectra and improvement in spectral measuring mode.