The specificity and sensitivity of each antibody is thoroughly validated in the New Product Development stage. This is done by staining multiple target cells with either single- or multi-color analysis or by other testing approaches. The QC specifications and testing SOPs and gold standard for each product are then developed. 

The functional performance of each batch of BioLegend products is strictly QC-tested according to the established QC procedures. In general, each product is tested using the following criteria: 

  1. Staining of 1-3 target cell types with either single- or multi-color analysis detailed in the QC specification (including positive and negative controls). The tested cells can be primary cells and/or cell lines known to be positive or negative for the target antigen.
  2. Each batch product is validated by QC testing with a series of dilutions to make sure the product is working within expected antibody titer range. 

  3. Each batch is compared to an internally established "gold standard" to maintain batch-to-batch consistency.
  4. When applicable, our products are side-by-side tested with our competitors' products to make sure that BioLegend's products exceed or are at least the same quality.
  5. For most tandem dye-conjugated products, color compensation is examined in order to verify tandem integrity.