> For the complete documentation index, see [llms.txt](https://docs.rplpeptides.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rplpeptides.com/docs/glossary/quality-control/coa.md).

# Certificate of Analysis (COA)

## Definition

A Certificate of Analysis (COA) is an official document issued by the manufacturer that reports the quality testing results for a specific batch of a product. For peptides, it includes purity, identity, and other quality data.

## Overview

The COA is the most important quality document for research peptides. It provides batch-specific evidence that the product meets its stated specifications. Every batch of RPL Peptide products is tested and accompanied by a COA.

## Technical Explanation

**COA Components:**

| Section              | Information Provided                           |
| -------------------- | ---------------------------------------------- |
| Product Information  | Product name, catalog number, batch/lot number |
| Manufacturer Details | Company name, facility location                |
| Testing Methods      | HPLC, MS, appearance, pH, etc.                 |
| Test Results         | Purity (%), identity confirmation, appearance  |
| Specifications       | Acceptance criteria for each test              |
| Analytical Data      | HPLC chromatogram, mass spectrum               |
| Certifying Signature | Authorized QC signatory                        |

**Verification Workflow:**

1. Check batch number matches product packaging
2. Confirm test results meet specifications
3. Review HPLC chromatogram for clean profile
4. Verify MS data confirms molecular weight
5. Check document authenticity (watermark, digital signature)

## Importance in Peptide Documentation

The COA is the primary quality assurance document for peptide procurement. Researchers should always verify that the COA matches the product received. A comprehensive COA demonstrates the manufacturer's commitment to quality.

## Related Terms

* [Specification](/docs/glossary/quality-control/specification.md)
* [Batch Number](/docs/glossary/quality-control/batch-number.md)
* [Lot Number](/docs/glossary/quality-control/lot-number.md)
* [HPLC](/docs/glossary/analytical-terms/hplc.md)
* [Mass Spectrometry](/docs/glossary/analytical-terms/mass-spectrometry.md)
* [Acceptance Criteria](/docs/glossary/quality-control/acceptance-criteria.md)

## Frequently Asked Questions

**Q: Should every product shipment include a COA?** A: Yes. Each batch/lot should have its own COA reflecting the actual testing of that specific batch. Generic COAs are not acceptable for quality verification.

**Q: What should I verify first on a COA?** A: First, confirm the batch/lot number matches the product label. Then check that the purity meets the minimum specification (e.g., ≥98%). Finally, verify the molecular weight matches the expected value.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.rplpeptides.com/docs/glossary/quality-control/coa.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.