NPPB is primarily used in scientific research to study ion channels, particularly chloride channels. It acts as a potent inhibitor of these channels, making it a valuable tool for understanding their role in cellular processes. Researchers utilize NPPB to investigate the physiological and pathological functions of chloride channels in various tissues, including the kidneys, lungs, and nervous system. Its application extends to studies on cystic fibrosis, where chloride channel dysfunction plays a critical role. Additionally, NPPB is employed in electrophysiological experiments to block chloride currents, helping to elucidate the mechanisms of ion transport and cell signaling.