MQAE is widely used as a fluorescent chloride indicator in biological research. It is particularly valuable in studying chloride ion transport and concentration within cells, making it a key tool in neurobiology and physiology. Researchers employ MQAE to monitor chloride dynamics in neurons, which is crucial for understanding processes like synaptic inhibition and neuronal excitability. Additionally, it is utilized in cell imaging techniques to visualize chloride flux in live cells, aiding in the investigation of diseases related to chloride channel dysfunction, such as cystic fibrosis. Its high sensitivity and specificity for chloride ions make it a preferred choice in experimental studies.