TSQ is widely used as a fluorescent probe for the detection and quantification of zinc ions (Zn²⁺) in biological systems. Its high selectivity for zinc allows researchers to monitor intracellular zinc levels in live cells, making it valuable in neuroscience and cell biology studies. TSQ is particularly useful in visualizing zinc distribution in synaptic vesicles of neurons, where zinc plays a role in neurotransmission. It is also applied in histochemistry to stain zinc-rich tissues, aiding in the study of zinc homeostasis and its involvement in physiological and pathological processes. Additionally, TSQ has been employed in screening assays for zinc transporters and metalloproteins due to its sensitivity and low background fluorescence in the absence of zinc.