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].

Guidelines (The following is our recommended protocol. This protocol is provided as a guide only and should be modified to suit your specific needs).
1.1 Preparation of Stock Solution
Prepare a 1 mg/mL stock solution in ddH2O.
Note: The stock solution is recommended to be stored in aliquots at -80°C in the dark.
1.2 Preparation of Working Solution
Dilute the stock solution with cell culture medium to prepare a 10 μg/mL working solution.
Note: Please adjust the working solution concentration according to actual conditions and prepare it immediately before use.

2. Cell Staining
2.1 Add the 10 μg/mL working solution to the cell culture medium.
2.2 Incubate at room temperature for 6-12 hours.
3.4 Aspirate the dye working solution and observe using a fluorescence microscope (Ex/Em = 561/595 nm).
Note: If you want to treat the activity of cell lysosomes, you should ensure that the lysosome activity is completely destroyed before adding the dye. Otherwise, the lysosomes that are still active during staining can degrade DQ-BSA-Red, resulting in partial color development.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Solid

Blue to dark blue

[DQ-BSA-RED]

Shipping with dry ice.

-80°C, protect from light

• [1]. Marwaha R, et al. DQ-Red BSA Trafficking Assay in Cultured Cells to Assess Cargo Delivery to Lysosomes. Bio Protoc. 2017 Oct 5;7(19):e2571.  [Content Brief]