A novel fluorescent sensor for evaluating pH changes in organophosphorus pesticides-treated cells and C. elegans

pH plays an important role in the evaluation of the healthy status in versatile circumstances. The fluctuation of pH could be affected by complex internal and external stimuli. Especially, the abnormal pH changes is a common characteristic of organophosphorus pesticides (OPs)-caused damage owing to the irreversible inhibition of acetylcholinesterase (AChE) activity. Therefore, the rapid and efficient detection of pH changes is of great significance for predicting the OPs poisoning in living system. However, quick and convenient detecting pH levels in living cells is still limited by the lack of effective chemical tools. Here, a novel fluorescent probe TH-1 based on ESIPT mechanism was synthesized, showing specific fluorescent effects in different pH solutions. Importantly, the AChE catalyzed the hydrolysis product of acetylthiocholine iodide (ATCh) and changed the pH of solution, which influence its fluorescent intensity. Moreover, the probe TH-1 was applied to detecting the pH levels in living cells and C. elegans, providing an efficient chemical sensor for revealing the potential mechanisms of OPs in physiological and pathological processes.