Storage Instructions:

All of our manufacturing partners produce peptides using the Lyophilization (Freeze Drying) process, ensuring products maintain stability for shipping and storage for 6+ months. 

Once peptides have been received, it is imperative that they are kept cold and away from light. If the peptides will be used immediately, or in the next several days, weeks or months, short-term refrigeration under 4°C (39°F) is generally acceptable. Lyophilized peptides are usually stable at room temperatures for several weeks or more, so if they will be utilized within weeks or months such storage is typically adequate.

However, for longer-term storage (several months to years) it is more preferable to store peptides in a freezer at -80°C (-112°F). When storing peptides for months or even years, freezing is optimal in order to preserve the peptide's stability.

Third-party testing

Peptide Partners is committed to providing high-purity peptides at wholesale prices by frequently auditing its manufacturing partners using third-party laboratories. Independent analysis is vital to ensuring the quality and authenticity of your research peptides. Never trust a supplier that doesn't submit to third-party testing. Never trust a certification that cannot be independently verified. All of the certificates that we provide can be validated on the third-party laboratory's website. 

Each product description contains a Manufacturer ID corresponding to the producer of that product. The table below contains the most recent third-party analyses for all manufacturers and peptides listed on Peptide Partners. 

Current Purity certifications

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Current Endotoxin Certifications

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Current Sterility Certifications

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Verifiable certificates

When obtaining research peptides, it is essential to validate the authenticity of the Certificate of Analysis (COA). Certificate fraud runs rampant throughout the research peptide supply community. The two most common forms are doctored images and stolen certificates. You can check for these two by making sure the third-party laboratory's website shows that the certificate belongs to the supplier and the values haven't been doctored. TrustPointe Analytics provides a few simple rules for verification:

When reviewing a COA, the first thing that should be done is to look for a way to verify that the COA is legitimate – either a link, key, or QR Code. That should take you to the laboratory’s website, not a third party website. If you follow the link and it does not take you to the laboratory’s website (URL), it is likely falsified. Finally, verify that the information on the COA provided matches the COA on the laboratory’s website. People who falsify COAs cannot access the laboratory’s website, so they are unable to alter the original COA.

Beware of fraudulent laboratories

Not only must one remain vigilant about potentially fraudulent certificates, one must also be aware that there are third-party laboratories whose results cannot be considered reliable or scientifically valid. Unfortunately, there is significant evidence to suggest that one of the most popular third-party testing labs does not use scientifically sound methodologies and, in some cases, has fabricated results. There isn't an easy remedy for this problem, but when labs are particularly bad, there tend to be a lot of discussion threads on various social platforms.

Interpreting Endotoxin Results (via TrustPointe)

Our friends at TrustPointe have provided the following detailed explanation to help interpret the results of the endotoxin testing.

We use the Charles River Endosafe PTS system to test for bacterial endotoxins following USP <85> guidelines:

• USP <85> Bacterial Endotoxin Result: <x.xx EU/mL
  Because it’s reported as “<x.xx” this indicates the test did not detect endotoxin above the detection limit of the cartridge.
• If a result is above the limit of detection of the cartridge, it will be reported as a number (without the "<").

The following are suitability parameters that verify the system was working properly and the sample prep dilution is appropriate for accurate results. Peptides often interfere with endotoxin detection due to their tendency to bind or mask endotoxins, which can lead to inaccurate low results. To overcome this, samples are typically tested at a large dilution to reduce matrix interference and ensure reliable recovery and detection in compliance with USP <85>.  If the dilution is not correct, the run will fail suitability and we'll need to adjust the dilution to ensure accurate results. We provide the suitability data to customers for transparency and so they can be confident in the results.

USP <85> Sample CV %:

• CV stands for coefficient of variation, a measure of repeatability.
• For our lab, CV has to be <25% or the result to be considered valid

USP <85> Spike CV %:

• This refers to the precision of the positive control (spiked sample).
• Again, for our lab CV has to be <25% or the result to be considered valid

USP <85> Spike Recovery

• This tells us how much of the known endotoxin spike was recovered from your sample.
• The acceptable range is 50–200% per USP <85>