The generation of critical reagents is both cost and labor intensive. Therefore, it is important that they are thoroughly characterized and managed in order to ensure the integrity of the assays in which they are used. Below we define critical reagents and describe the best practices for their characterization. We also demonstrate how Bio-Rad applies these industry specified best practices in characterizing the critical reagents that we produce.
Critical reagents are the indispensable components of ligand binding assays (LBAs). Their unique characteristics are essential to the appropriate performance of LBAs. The categories of critical reagents include antibodies, peptides, engineered proteins, complex biologics, chemically synthesized molecules, solid supports and matrices, as well as antibody, protein and peptide conjugates. Because they are typically generated by biological processes, critical reagents are inherently prone to lot to lot variation. Consequently, proper management and characterization of these reagents in bioanalytical laboratories is important for successful drug development.
Characterization of critical reagents for ligand binding assays
The characterization and management of critical reagents varies between bioanalytical laboratories. Up until 2012, there was no consensus among these laboratories on the best practices for analyzing and managing critical reagents, which is crucial for clinical research. In an effort to standardize critical reagent management and characterization, a group of scientists from the Global Bioanalysis Consortium harmonization team outlined a set of recommendations and best practices for the life cycle management, characterization and supply of critical reagents used in LBAs (O'Hara et al. 2012). For characterizing critical reagents, the agreed best practices centered on assessing sensitivity, specificity and reproducibility. Below we provide a summary of these best practices.
Best practices for characterizing critical reagents
Bio-Rad manufactures anti-biotherapeutic antibodies for scientists involved in preclinical research, clinical trials and patient monitoring for innovator and biosimilar products. These anti-biotherapeutic antibody reagents are important for anti-drug antibody and pharmacokinetic assays. Bio-Rad takes a similar approach to characterizing these antibodies as outlined by the global bioanalysis consortium. We apply the best practices outlined for quality control and antibody batch characterization as part of the manufacturing and development of our anti-biotherapeutic antibody portfolio. We specifically assess the reproducibility and sensitivity of our anti-biotherapeutic antibodies by testing purity, consistency, stability, activity, aggregation and affinity. Every new antibody is assessed by rigorous quality control procedures to ensure a high quality antibody every time. This helps the assay developer with critical reagent life cycle management, characterization and supply, and ensures optimal assay performance over time.
To learn more, check out our technical article where we highlight our anti-biotherapeutic antibody range and provide actual data of our analyses.
O'Hara DM et al. (2012). Ligand binding assay critical reagents and their stability: Recommendations and best practices from the global bioanalysis consortium harmonization team. AAPS J 16, 504-515.