Author name: Maple Research Labs

A peptide can be 99% pure and still be one-fifth trifluoroacetate by weight. What the counterion is, why HPLC misses it, and why it is not inert.

Why HPLC purity is blind to metals, what ICH Q3D actually requires, how ICP-MS works, and why a copper peptide inverts the whole question.

Sterility and bioburden are different questions with different compendial tests. What each one proves, and what a peptide COA actually carries.

ICH Q3C classes, USP 467 headspace GC, and why a 99% pure peptide can still be several percent solvent by mass. What the certificate omits.

How USP <905> content uniformity, batch sampling, and fill accuracy actually work for lyophilized research peptides — and what a COA does not tell you.

How LAL and recombinant Factor C endotoxin assays actually work, what USP <85> and <86> require, and what a research peptide COA does and does not certify.

Third-party or in-house peptide testing? Eight national metrology labs measured one oxytocin vial and disagreed by 220 mg/g. What that means for a COA.

Reporting, identification and qualification thresholds are three different obligations. Why a single peptide purity percentage satisfies none of them.

Where the 98% peptide purity number comes from, why ICH excludes peptides from its own thresholds, and what a US research COA should report.

MS confirmed is not one claim. What MALDI-TOF and LC-MS/MS each certify about peptide identity, and what a US research COA should state.