Resolution of matrix interference: quantitative and quasi-quantitative ligand-binding assays case studies
Background: Matrix effects pose a constant challenge in developing robust ligand-binding assays to be validated for use in nonclinical and clinical study support. When notable matrix effects of any kind are present, it can render an otherwise sound method ineffective. We present two case studies detailing the mitigation of observed matrix effects. Method: A dimeric protein was removed from unknown samples in an anti-therapeutic antibody assay through protein extraction. Nonspecific matrix effects in a quantitative ligand-binding assays were mitigated through development of a specialized buffer. Results: The protein extraction method reproducibly reduced the artificially high responses of naïve samples, enabling the accurate detection of anti-therapeutic antibodies. Design of experiments was used to evaluate and select the optimal components and associated concentrations in order to reduce the observed matrix effect to acceptable limits. Conclusion: Our results suggest there are multiple techniques available for the bioanalytical scientist to mitigate both matrix effects in ligand-binding assays.