A high-selectivity NIR fluorescent probe for detection of nitric oxide in saliva samples and living cells imaging

In this study, a near-infrared Changsha dye (CS)-based fluorescent probe CS-Se for nitric oxide (NO) detection was designed and synthesized. The reaction between CS-Se and NO generated a highly selective and sensitive optical response that resulted in a fluorescence "turn-on" effect with a detection limit of as low as 28 nM. Saliva samples from 10 healthy individuals and patients with oral diseases were collected. The results showed that the level of NO concentration was positively correlated with the oral diseases. Cell experiments also showed that the probe had low toxicity and was able to monitor endogenous NO. This study presents the first fluorescent probe that can be used to measure the concentration of NO in oral diseases. This probe is a promising tool for monitoring and evaluating the progression of oral diseases.