DQ-BSA-RED

DQ-BSA-Red is a bovine serum albumin labeled with a red fluorescent dye that can be used to detect lysosomal activity. The excitation wavelength and emission wavelength of DQ-BSA-Red are 590 nm and 620 nm, respectively. The BSA molecule in DQ-BSA-Red is labeled with high concentration of red fluorescent dye in multiple sites, which shows high fluorescence self-inhibition. Once DQ-BSA-RED enters the lysosome, DQ-BSA is cleaved by lysosomal proteases, resulting in unquenched and released fluorescent fragments, emitting bright fluorescence. Inactivated lysosomes are unable to degrade the BSA protein and thus have a lower or even no fluorescent signal[1].