Koi Peptides sets 99% purity standard for research peptides

Koi Peptides said June 16 it has formalized a ≥99% HPLC purity standard across its research peptide catalog, with per-batch verification, mass spectrometry confirmation and lot-specific COAs. The move is meant to improve reproducibility for qualified labs using research-use-only material.

Why it matters: - Koi Peptides is trying to reduce one of the biggest variables in peptide research: uncertainty about what is actually in each vial. - A documented per-batch purity standard can improve reproducibility for qualified laboratories and make lot-to-lot comparisons easier. - The company is also positioning its products around research compliance, not therapeutic use.

What happened: - Koi Peptides announced a ≥99% HPLC purity standard across its research peptide line on June 16, 2026. - The standard applies to research-use-only material supplied to qualified laboratories. - Every batch is verified by reverse-phase HPLC, confirmed by mass spectrometry, screened for bacterial endotoxin and shipped with a lot-specific Certificate of Analysis. - The company said third-party release, where used, follows ISO/IEC 17025 accreditation.

The details: - The purity figure is expressed as area percent, meaning ≥99% of the UV-absorbing peptidic material detected corresponds to the target peptide peak. - RP-HPLC separates the sample on a C18 column by gradient elution using water and acetonitrile, with UV detection at 210 to 220 nm. - HPLC purity measures the chromatographic profile of UV-absorbing peptidic material, while net peptide content measures actual peptide mass relative to non-peptidic components such as water, residual solvent and counterions. - Many synthetic peptides ship as lyophilized TFA salts, so a ≥99% HPLC-pure peptide can still have a net peptide content below 100% by weight. - Net peptide content typically ranges from 50% to 90%, and amino acid analysis is used when mass-based concentrations must be precise. - Industry-baseline HPLC purity for high-purity research peptides is about ≥95%, with difficult or long sequences sometimes purified at lower levels depending on synthesis challenges and intended use. - Koi Peptides says its standard is set at ≥99% and is backed by per-batch COA evidence. - Each batch is profiled by RP-HPLC, with the target peak integrated against total peak area for the area-percent figure. - Closely eluting impurities, including deamidated or oxidized variants, are quantified in the same analysis. - Electrospray ionization mass spectrometry and MALDI-TOF are used to compare intact mass against the theoretical molecular weight and flag truncated or deleted variants. - The company said a clean peak can still be the wrong molecule, which is why identity testing is required alongside purity. - Each lot COA lists HPLC purity, mass spectrometry identity, endotoxin status, batch and lot numbers, synthesis date, counterion and method conditions. - Researchers can review the COA on the website before placing an order. - The company said all products remain research-use-only material and are not for human or animal consumption. - The disclaimer says the ≥99% figure is an analytical specification, not a claim of safety, efficacy or fitness for human use. - The disclaimer also says the products are not dietary supplements or natural health products, are not FDA-approved for therapeutic use and do not come with reconstitution, dosing or administration guidance.

Between the lines: - Koi Peptides is leaning on documentation and testing to differentiate itself in a market where gray-market peptide products have often drawn concerns about mislabeling, contamination or missing active ingredient. - The emphasis on lot numbers, COAs and method data suggests the company is selling traceability as much as purity. - The regulatory language also draws a clear line between research supply and approved-drug or compounding pathways. - The release notes that the FDA issued more than 50 warning letters in September 2025 and that in April 2026 the agency procedurally removed certain peptides from the 503A Category 2 list. - The FDA also said removal from Category 2 does not authorize compounding.

What's next: - Researchers can use the batch number on each vial to verify the corresponding COA before starting work. - Koi Peptides said qualified buyers remain responsible for compliance with applicable regulations. - The Pharmacy Compounding Advisory Committee is scheduled to review seven peptides on July 23 and 24, 2026.

The bottom line: - Koi Peptides is making a quality-control pitch: higher documented purity, batch-level verification and stronger traceability for research peptides, but no change in the products' non-therapeutic status.