The Thermo Scientific Pro-Detect Rapid V5 Competitive Assay Kit is a single-use, dipstick lateral flow kit for quick, easy detection of V5-tagged proteins in protein expression and purification systems. This lateral flow assay uses membrane-based strips coated with dye-bound conjugated antibodies specific to V5 tag to provide a qualitative detection within ten minutes. This assay can be used to detect V5-tagged proteins directly from cell culture media (supernatant) or cell lysates without any special instrumentation or handling.

Features of the Pro-Detect Rapid competitive assay kits:
• Easy to adopt—lateral flow strips can be used early in and throughout expression to monitor and confirm expression of desired protein-tagged target
• Simple, fast method—simply dilute sample using provided diluent and dip in the lateral flow strip for qualitative results within 5-10 minutes
• Sensitive—detect protein tags in supernatant or cell lysate samples down to low μg/mL concentrations
• Specific—assay does not cross-react with common lysis and protein preparation reagents
• Reliable—results are similar to other antibody immunoassays, including western blot and ELISA
• Long shelf life—stable for at least one year at 4°C

Each Pro-Detect Rapid competitive assay is performed by simply adding a properly diluted tissue culture supernatant, lysate, or purified protein sample to a test tube or microplate well and dipping in a lateral flow strip. Gold-conjugated detection antibodies embedded in the strip form complexes with the tagged protein in the sample. In the presence of target protein tag, the dye-bound conjugated antibodies will bind to the tagged protein present in the sample instead of the protein tag bound at the test lines. Therefore, in a positive result, a competitive lateral flow assay will show decreasing intensity of the visible test lines until all test lines have disappeared. When there is no target protein tag present, the dye-bound conjugated antibodies specific to the target will bind at the test line(s), resulting in visual test lines in a negative result.