Peptide Reference Standard

Demand for peptide reference standards continues to grow across pharmaceutical analysis, biomarker quantification, proteomics research, and clinical mass spectrometry. The rapid expansion of peptide drug pipelines, combined with the emergence of antibody-drug conjugates (ADCs) and peptide-drug conjugates (PDCs), has driven increasingly stringent regulatory expectations for related substance control in peptide APIs and formulations — including sequence variants, oxidation products, deamidation products, dimers, and truncated sequences, all requiring high-purity peptide standards as analytical benchmarks.

In bioanalysis, LC-MS/MS targeted protein quantification by MRM or PRM acquisition is rapidly gaining adoption in clinical diagnostics, biomarker validation, and quantitative proteomics. Stable isotope-labeled peptides (SIL peptides) used as internal standards effectively correct for matrix effects and variable proteolytic efficiency, serving as the central component for achieving accurate absolute quantification in these workflows. Peptide standards are also widely used for peak assignment in peptide mapping analysis and as quantitative references in dissolution and bioequivalence studies for peptide drug products.

CATO Research Chemicals Inc. offers a complete range of catalog and custom-synthesized peptide reference standards. The synthesis platform supports Fmoc and Boc solid-phase strategies, incorporation of non-natural and chiral amino acids, disulfide bond formation, and cyclic peptide synthesis, covering linear, cyclic, and modified peptide structures. Purity is confirmed by reverse-phase HPLC and structure verified by ESI-MS or MALDI-TOF, with NMR data available on request. Custom orders are accepted by sequence, purity grade (research to GMP), isotope labeling (deuterium, ¹³C/¹⁵N), and packaging scale from milligram to gram quantities.