Purity Guarantee

    All PeptX products are research reagents supplied strictly for laboratory research use only (RUO). Each product states a guaranteed minimum purity. We carry out independent random QC testing on our stock, with results published in our COA library.

    What “99%+” means

    “Typically 99%+ purity (HPLC)” describes the purity commonly achieved for standard research peptides by HPLC. It is not a guarantee for every compound. Guaranteed minimum purity varies by compound chemistry and is stated on each product:

    • Standard research peptides: guaranteed ≥98% (typically 99%+)
    • Large proteins / growth factors (e.g. HGH, IGF-1 LR3): ~95%
    • Copper complexes (GHK-Cu) and NAD⁺: ≥98%
    • Blends: a guaranteed minimum for each active
    • Biologics (e.g. HCG): specified by potency / units, not purity %
    • Diluents (bacteriostatic / sterile water): sterile, USP grade

    Our guarantee

    If you independently test a batch with an accredited laboratory and the result is below its stated guaranteed minimum purity, raise a dispute within 14 days of delivery with your test report and supporting information. We review each case and, where the result is verified, refund or re-ship the affected item, in line with our Refund & Returns terms. We may, at our discretion, review claims raised up to 30 days after delivery.

    Purity figures relate to the compound as supplied (lyophilised) and do not account for the buyer's handling, storage, or reconstitution. Research use only, not for human or animal consumption.

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