Cystine is the source of the antioxidant glutathione, which plays an important role in the redox equilibrium within cells. The cystine/glutamate transporter (xCT) on the cell membrane is one of the amino acid transporters that transports extracellular cystine into the cell and intracellular glutamate into the cell in a ratio of 1:1. xCT regulates intracellular glutathione synthesis through cystine uptake and maintains cellular redox equilibrium. When the xCT activity on the cell membrane decreases, the ability of the cell to uptake cysteine may decrease, which may lead to cell ferroptosis. In recent years, the association between xCT and related diseases such as cancer, neurodegenerative diseases, and immunity has gradually become one of the research hotspots. This kit is a convenient kit for detecting cystine uptake ability of cells by fluorescence method. Cystine analog, like cystine, can be transported into cells through xCT on the cell membrane. Cystine analog react with fluorescent probes and emit fluorescence. Therefore, the ability of cell cystine uptake can be determined by detecting the fluorescence intensity generated by cystine analog
