Fluorescein sodium loaded by polyethyleneimine for fundus fluorescein angiography improves adhesion.

Aim: To improve the retention of fluorescein sodium (FS) as a kind of clinical contrast agent for fundus fluorescein angiography (FFA). Materials & methods: Polyethyleneimine (PEI) was designed to synthesize PEI-NHAc-FS nanoparticles (NPs), and the formed NPs were characterized by both physicochemical properties and their effects on FFA. Results: Compared with free FS, PEI-NHAc-FS NPs showed similar optical performance, and could obviously reduce cellular adsorption and uptake both in vitro and in vivo, which could promote the metabolism of NPs in ocular blood vessels. Conclusion: PEI-NHAc-FS NPs represent a smart nanosize fluorescence contrast agent, which hold promising potential for clinical FFA diagnosis, therapy and research work.