Frequently asked questions

Every lot. Each synthesis run gets its own release panel and its own certificate, published against the lot number printed on the vial. Testing one run and shipping certificates from it for a year is the most common shortcut in this category, and it is exactly what per-lot publication makes impossible to hide.

Independent laboratories accredited to ISO/IEC 17025. Each certificate names the laboratory and its accreditation rather than saying 'third-party verified' — a badge you cannot check against a registry is not evidence of anything.

Because each has a blind spot the other covers. HPLC quantifies but does not identify: a peak at a given retention time is consistent with your compound and with an unknown number of others. Mass spectrometry identifies but cannot distinguish stereoisomers, aspartimide rearrangements or, at loose tolerances, cyclisation state. Run together, a lot that passes both is very unlikely to be wrong in a way either would have missed alone.

It is an area-percent figure: the area under the main HPLC peak divided by the total peak area at 214 nm. It tells you the relative proportion of UV-absorbing species. It does not tell you how much peptide is in the vial — salt and water contribute no peak area at all. Net peptide content is the number that governs your concentrations, and we report it separately and label vials by it.

Failed lots are not released, so they are not sold and do not appear in the archive. Retired and superseded lots do stay published. If a released lot were later found to be out of specification, it would be marked recalled on its own page rather than removed — quietly deleting a record is the failure mode public archives exist to prevent.

Orders ship from our Mount Pleasant, SC facility once payment is received and confirmed. Standard delivery is 3–5 business days; 2-Day and Overnight are available at checkout.

Yes. Everything ships lyophilised in an insulated cold pack as standard, not as a paid upgrade. Lyophilised peptide tolerates short ambient excursions far better than reconstituted material, but the cold pack keeps the margin comfortable in summer transit.

Yes, by tier: Standard is free over $200 (otherwise $14.99), 2-Day is free over $500 (otherwise $29.99) and Overnight is free over $1,000 (otherwise $49.99). Every tier ships in an insulated cold pack by UPS or FedEx.

Currently the United States only. Research chemical import rules vary considerably by country and we would rather ship nowhere than ship somewhere we cannot do so lawfully and reliably.

Where we're required to collect it — currently South Carolina — at the combined state and local rate for your delivery address, shown at checkout before you order. Resale buyers and tax-exempt institutions: send us your resale or exemption certificate and we'll exempt your account.

Credit or debit card. Placing an order does not charge you: we email you a secure payment link from our payment processor, and the order ships once payment is completed. Institutional purchase orders are available for university and corporate accounts — contact us to set one up.

Lyophilised, at -20 °C, desiccated and protected from light. Most compounds are stable for two years under those conditions; the retest date is on each certificate. Let a vial reach room temperature before opening — a cold vial draws in moist air that condenses on the cake.

It depends entirely on the sequence, and we give a per-compound answer rather than a blanket one. BPC-157 holds 30 days at 2–8 °C with under 2 % loss. Unmodified sermorelin gets 7 days. NAD+ and reduced glutathione should be prepared fresh. Any supplier quoting one number for the whole catalog is quoting a marketing figure.

Shaking generates an air-water interface and shear, and peptides denature at interfaces. The visible sign is foam; the invisible sign is aggregated material that no longer counts toward your concentration. Add diluent slowly down the vial wall and swirl. Long acylated peptides are the most sensitive.

For most compounds, no. For strongly cationic peptides such as LL-37, low-protein-binding tubes and tips are genuinely necessary — adsorptive loss to ordinary polypropylene is measurable at working concentrations and will look like degradation in your data.

No. Every product is supplied strictly for laboratory research use. These are not drugs, foods, cosmetics or medical devices; none has been evaluated by the FDA; and none is intended for human consumption, veterinary use, or any form of in-vivo administration.

No. Certus Peptides is a research chemical supplier. We are not a 503A compounding pharmacy and not a 503B outsourcing facility, and we do not hold ourselves out as either. Those are separate regulatory categories with separate requirements.

Qualified researchers and institutions purchasing for legitimate laboratory research. By ordering you confirm the material will be used only in a laboratory setting by or under the supervision of someone qualified to handle it, and that you accept responsibility for compliance with the regulations applicable in your jurisdiction.

Send us the lot number. We replace the order and pull the batch while we investigate. That commitment only means something because the certificate is public and specific enough for you to check us against — which is the point of publishing it that way.