WST-1 is a kind of water-soluble tetrazolium salt. WST induces the intracellular mitochondrial dehydrogenase to conduct NADH-dependent enzyme digestion reaction, releasing the water-soluble methyl benzene product. WST-1 can be used for the detection of cell proliferation and cytotoxicity, via the determination of the light absorption value at 450 nm^[1].

Preparation of WST-1 working solution
1.1 Preparation of the stock solution
Dissolve 10 mg of WST-1 in 1 mL of DMSO to obtain 10 mg/mL of WST-1.
1.2 Preparation of WST-1 working solution
Dilute the stock solution in serum-free cell culture medium or PBS to obtain 5-10 μM of WST-1 working solution.
Note: Please adjust the concentration of WST-1 working solution according to the actual situation.

Cell staining
2.1 Cell preparation.
For suspension cells: Centrifuge at 1000 g at 4°C for 3-5 minutes and then discard the supernatant. Wash twice with PBS, 5 minutes each time.
For adherent cells: Discard the cell culture medium, and add trypsin to dissociate cells to make a single-cell suspension. Centrifuge at 1000 g at 4°C for 3-5 minutes and then discard the supernatant. Wash twice with PBS, 5 minutes each time.
2.2 Add 1 mL of WST-1 working solution and 1-methoxy PMS (2 mM), and then incubate at room temperature for 2 h.
2.3 Use microplate reader detect 450/690 nm OD.

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

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 2 years; -20°C, 1 year (sealed storage, away from moisture and light). When stored at -80°C, please use it within 2 years. When stored at -20°C, please use it within 1 year.

* Note: If you choose water as the stock solution, please dilute it to the working solution, then filter and sterilize it with a 0.22 μm filter before use.

• [1]. Munetaka ISHIYAMA, et al. A new sulfonated tetrazolium salt that produces a highly water-soluble formazan dye. Chem. Pharm. Bull. 1993, 41(6): 1118-1122.