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 (NO2−) and assessing the irritation in jellyfish cell. The nanoprobe was assembled by linking neutral red to the surface of polyethylene glycol (PEG) modified NaGdF4:Yb,[email protected]4 core/shell nanoparticles. The nanoprobe could efficiently capture the NO2− 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 NO2− increasing. Moreover, the irritation of NO2− was assessed in jellyfish cells using neutral red modified fluorescent nanoprobe based on cell imaging and spectrum signals, that NO2− 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.