Dye-modified core/shell NaGdF4:Yb,Er@NaYF4 nanoparticles for the detection and irritation assessment of NO2−

Upconversion nanoparticles (UCNPs) have great potential applications in biological imaging, medical treatment and optical sensing. However, the development of an inorganic-organic hybrid fluorescent probe to accurately detect noxious ions and scientifically assess irritation in vivo remains a challenge. Herein, we demonstrate a fluorescent nanoprobe for detecting nitrites (NO 2 − ) and assessing the irritation in jellyfish cell. The nanoprobe was assembled by linking neutral red to the surface of polyethylene glycol (PEG) modified NaGdF 4 :Yb,Er@NaYF 4 core/shell nanoparticles. The nanoprobe could efficiently capture the NO 2 − in jellyfish and simultaneously visualize the process. It's known that the intensity ratio of green to red emission (IRGRE) of neutral red modified upconversion nanoparticles increases linearly with the amount of NO 2 − increasing. Moreover, the irritation of NO 2 − was assessed in jellyfish cells using neutral red modified fluorescent nanoprobe based on cell imaging and spectrum signals, that NO 2 − has irrecoverable injury to the cells. This work based on dye-modified upconversion luminescence nanoprobe is expected to shed further light on the biological analysis and detection of ions.