Insulin analogues represent a major and growing class of biotherapeutics, and their quantitation is an important focus of commercial and public effort across a number of different fields. As LC-MS has developed, it has become an increasingly practicable and desirable alternative to ligand-binding-based approaches for quantitation of this class of compounds. The sensitivity challenge of measuring trace levels of this large peptide molecule in a protein-containing matrix is considerable; however, different approaches to detection, extraction and separation are described to overcome this challenge, including immunoaffinity capture, SPE and low-flow HPLC. Considerations such as bioanalytical assay acceptance criteria and antidrug antibody effects during drug development are included, alongside descriptions of recent sports doping and clinical applications. Factors affecting the correlation and agreement of MS with biological ligand-binding methods are discussed, with ways to anticipate and appreciate differences between the values derived from each technique. The 'future perspective' section discusses the likely trend towards MS-based analysis for these compounds and the impact of HRMS. A high degree of scientific creativity, combined with science-defined regulatory approaches that define suitable validation criteria, will be needed to meet the demanding requirements for high-throughput analysis of insulin by LC-MS.
Abstract. Consensus practices and regulatory guidance for liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS) assays of small molecules are more aligned globally than for any of the other bioanalytical techniques addressed by the Global Bioanalysis Consortium. The three Global Bioanalysis Consortium Harmonization Teams provide recommendations and best practices for areas not yet addressed fully by guidances and consensus for small molecule bioanalysis. Recommendations from all three teams are combined in this report for chromatographic run quality, validation, and sample analysis run acceptance.
Achieving sufficient selectivity in bioanalysis is critical to ensure accurate quantitation of drugs and metabolites in biological matrices. Matrix effects most classically refer to modification of ionization efficiency of an analyte in the presence of matrix components. However, nonanalyte or matrix components present in samples can adversely impact the performance of a bioanalytical method and are broadly considered as matrix effects. For the current manuscript, we expand the scope to include matrix elements that contribute to isobaric interference and measurement bias. These three categories of matrix effects are illustrated with real examples encountered. The causes, symptoms, and suggested strategies and resolutions for each form of matrix effects are discussed. Each case is presented in the format of situation/action/result to facilitate reading.
The introduction of ion-mobility separation into a bioanalytical LC-MS/MS method can remove unexpected isobaric interferences without the need to redevelop the chromatography.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.