1-methoxyPMS is a photochemically stable electron mediator between NAD(P)H and tetrazolium dyes.

The solid could be stored at room temperature.

General protocol for cck-8 assay:

1. Prepare cck-8 working solution: dissolve WST-8 (CSN12409) and 1-mPMS in ddH₂O to a final concentration of 500μM and 20μM, respectively.

2. Please ensure that the volume of the culture medium is just 100μL in every well.

Note: For WST-8 can be reduced, make sure that there is no reductant or oxidant in the culture media. If you add compound during cell culture, please wash every well for 2 times with PBS and add fresh culture medium before detection.

3. Add 100μL of cck-8 working solution into every well of 96-well plate.

4. Gently shake the plate to mix the solution well.

5. Incubate the plate in a CO₂ incubator at 37°C for 0.5-4h. After incubation, the colour of the solution should turn to orange.

6. Read the plate at 450 nm with a reference wavelength at 650 nm with an M-UVmax microplate reader.{{Ishiyama M, Miyazono Y, Sasamoto K, Ohkura Y, Ueno K. A highly water-soluble disulfonated tetrazolium salt as a chromogenic indica

1-methoxyPMS is a photochemically stable electron mediator between NAD(P)H and tetrazolium dyes. It is combined with WST-8 (CSN12409) in cell vitality assay (cck-8 assay).

[1] Nakamura S, Arimura K, Ogawa K, Yagi T. Use of 1-methoxy-5-methylphenazinium methyl sulfate (1-methoxyPMS) in the assay of some enzymes of diagnostic importance. Clin Chim Acta. 1980 Feb 28;101(2-3):321-6. doi: 10.1016/0009-8981(80)90260-0. PMID: 7357752.