Fluorescence Characteristics of DAST in Silica Nanoparticles

4-N, N-dimethylamino-4'-N'-methyl-stilbazolium tosylate (DAST) is well-known as one of the most important organic optical materials, but its fluorescence properties require further investigations. In this work, the fluorescence of DAST molecules encapsulated in silica nanoparticles (DAST@SNPs) was measured. Results reveal that blue-shift of the fluorescence peak and large enhancement of the fluorescence intensity were measured when DAST@SNPs were formed. Particularly, the fluorescence intensity of DAST@SNPs is 52.5 times stronger than that of pure DAST aqueous solution, meanwhile the emission peak of the former blue-shifts obviously from 604 nm for the latter to 591 nm.