What is a Certificate of Analysis (COA)?
A Certificate of Analysis is a document that records the analytical test results for a specific peptide lot. It typically documents the compound identity, the measured purity percentage, and the analytical tests performed, such as HPLC and mass spectrometry. The COA gives researchers an objective record of what was actually measured for the material they received, rather than a general product claim. Each COA is tied to a specific lot or batch number so results can be traced back to the exact material in hand. COAs are available on request and are used for research documentation purposes only.
What purity are your research peptides?
Research peptides are produced to a target purity of 99 percent or higher. Purity refers to the proportion of the intended peptide relative to other peptide-related substances in the sample, as measured by HPLC. A 99 percent target means the analytical methods aim to confirm that the large majority of the material is the intended compound. Actual measured purity for each lot is recorded on its Certificate of Analysis, which is available on request. These materials are intended for laboratory and in-vitro research use only and are not for human or animal consumption.
How are your peptides tested?
Peptides are third-party tested using two complementary analytical methods. Identity is confirmed by mass spectrometry, which measures the molecular mass to verify the compound is what it is labeled to be. Purity is measured by HPLC (high-performance liquid chromatography), which separates the sample into its components and quantifies the proportion that is the intended peptide. Together these methods document both what the compound is and how pure it is. The results for each lot are recorded on a Certificate of Analysis available on request. Testing supports laboratory research use only.
What is HPLC and what does it measure?
HPLC stands for high-performance liquid chromatography. It is an analytical technique that pushes a dissolved sample through a column, separating it into individual components based on how each interacts with the column material. In peptide testing, HPLC is used to measure purity by quantifying the proportion of the sample that corresponds to the intended peptide versus other peptide-related substances. The result is reported as a purity percentage on the Certificate of Analysis. HPLC does not by itself confirm identity, which is why it is paired with mass spectrometry for a complete analytical picture.
What is mass spectrometry used for in peptide testing?
Mass spectrometry is used to confirm the identity of a peptide. It measures the molecular mass of the compound, which can be compared against the expected mass for the intended peptide sequence. If the measured mass matches the expected value, this supports that the material is the labeled compound. Mass spectrometry answers the question of what the compound is, while HPLC answers how pure it is. Both results are documented on the Certificate of Analysis for each lot. These analyses support laboratory and in-vitro research use only.
Is the COA third-party or in-house?
Research peptides are third-party tested, and the Certificate of Analysis reflects analytical results from that testing. Third-party testing means the analysis is performed by a laboratory independent of the production process, which provides an additional layer of objectivity to the reported identity and purity values. The COA documents the methods used, including HPLC for purity and mass spectrometry for identity, along with the associated lot or batch number. COAs are available on request and are provided for research documentation purposes only.
How do I get a COA for my order?
A Certificate of Analysis is available on request. Researchers can request the COA that corresponds to the lot or batch number of the material they received, and the document will reflect the analytical results for that specific lot. Because COAs are tied to individual lots, providing the lot or batch number helps ensure the correct certificate is matched to the material in hand. Certificates are hosted on the /coa page where available. COAs are provided for laboratory research documentation only and do not constitute any approval for human or animal use.
What does 99% purity mean in practice?
A 99 percent purity result means that, as measured by HPLC, approximately 99 percent of the peptide-related material in the sample corresponds to the intended compound, with the remainder being other peptide-related substances. It is a measure of compositional purity, not a statement of suitability for any particular use. Purity is reported per lot on the Certificate of Analysis, so the exact measured value can vary slightly between batches. Researchers reviewing a COA can see the specific purity figure recorded for their lot. These materials are for in-vitro research use only.
Why does purity matter in peptide research?
Purity matters because impurities can introduce uncontrolled variables into experimental results. In laboratory research, substances other than the intended peptide may interfere with measurements, complicate interpretation, or reduce the reproducibility of an experiment. A higher, documented purity helps a researcher attribute observed results to the intended compound rather than to unknown contaminants. This is why purity is measured by HPLC and recorded on the Certificate of Analysis for each lot. Documented purity supports rigorous, repeatable laboratory work, which is the only intended use of these materials.
What is lot or batch tracking?
Lot or batch tracking is the practice of assigning a unique identifier to each production batch of a peptide and tying its analytical results to that identifier. Every Certificate of Analysis references a specific lot or batch number, so the documented identity and purity values correspond to the exact material a researcher received. This traceability lets researchers match their physical material to its test record and keep accurate experimental documentation. If a question arises about a specific vial, the lot number connects it back to its COA and testing history.
What impurities can a COA detect?
A Certificate of Analysis primarily documents purity as measured by HPLC, which quantifies the proportion of the sample that is the intended peptide versus other peptide-related substances that separate during analysis. The mass spectrometry result documents identity by confirming the molecular mass, which can also flag if the primary compound differs from what is expected. The specific substances reported depend on the analytical methods listed on the COA. Researchers should review the methods and results on each certificate to understand what was measured. These materials are for laboratory research use only.
Is endotoxin tested?
The standard Certificate of Analysis documents identity by mass spectrometry and purity by HPLC. Endotoxin is a separate type of test and is not part of the standard identity and purity analysis unless specifically listed on a given COA. Researchers who require endotoxin data should review the methods section of the certificate for their lot to confirm which tests were performed, and may inquire whether additional testing is available. Because these products are sold strictly for in-vitro and laboratory research use, the standard COA focuses on identity and purity rather than tests associated with any other application.
Can I verify the COA is real?
Yes. Each Certificate of Analysis references a specific lot or batch number, which lets a researcher confirm that the certificate corresponds to the material they received. Certificates are hosted on the /coa page where available, so the document can be matched against the lot number printed on the product. Researchers can also request the COA for their specific lot directly. Matching the lot number on the vial to the lot number on the certificate is the primary way to confirm that a COA applies to the material in hand. COAs are provided for research documentation purposes only.
What is net peptide content?
Net peptide content refers to the amount of actual peptide in a sample, separate from other non-peptide material such as residual water, salts, or counter-ions that can be present after synthesis. It differs from chromatographic purity: HPLC purity describes how much of the peptide-related material is the intended compound, while net peptide content describes how much of the total weight is peptide at all. Researchers calculating quantities for in-vitro work may need both figures. Where reported, these values appear on the Certificate of Analysis. These materials are for laboratory research use only.
Does higher purity cost more?
Higher purity peptides can cost more because achieving and verifying greater purity often requires additional purification steps and analytical testing. Research peptides here are produced to a 99 percent or higher purity target, with purity measured by HPLC and identity confirmed by mass spectrometry, and the verified results documented on each lot's Certificate of Analysis. Pricing reflects the production and testing involved in meeting that target. Researchers selecting materials should weigh the documented purity on the COA against the requirements of their specific laboratory application, since these products are sold for in-vitro research use only.
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