COA & Purity Science

qNMR peptide purity analysis measures how much peptide is actually present as a fraction of total sample mass, rather than […]

Capillary electrophoresis peptide purity analysis separates species by charge-to-size ratio rather than by hydrophobicity, which allows it to resolve impurities

Karl Fischer titration measures residual water in lyophilized research peptides. Why moisture skews net peptide content, drives solid-state degradation, and belongs on the COA.

Residual solvents are governed by ICH Q3C and USP 467 and measured by headspace GC, not by the HPLC assay behind a COA purity figure. A look at the limits, the method, and its documented blind spots.

Elemental impurities in research peptides are trace metals introduced by synthesis catalysts, equipment surfaces, and reagents, and reversed-phase HPLC cannot

Circular dichroism peptide research explained: how CD spectroscopy verifies secondary structure and catches misfolding that HPLC purity and mass data miss.

Trifluoroacetate counterions left on research peptides after HPLC purification can suppress cell proliferation at nanomolar concentrations, a variable invisible to standard purity numbers.

Peptide impurity profiling is the systematic identification and quantification of unwanted byproducts that arise during peptide synthesis, including truncated sequences,