Fictional peptide COA review exercise
Practice reading a peptide certificate of analysis: trace three vial labels to a fictional report, compare each result with its own criterion, and document what remains open.
Download the materials
- Printable worksheet
Standalone resource with instructions and a worked answer key.
- Blank COA review template (CSV)
Nine review prompts for capturing document evidence, questions and follow-up.
- License and attribution
CC BY 4.0 terms and a suggested credit.
Use this resource
- Read the fictional report and compare each of the three vial labels.
- Fill in the blank review CSV, keeping area percent and amount per vial in separate rows.
- Use the answer key to check your decision note and follow-up requests.
Before you start
Estimated time 20–30 minutes.
Prerequisites Basic percentage arithmetic and familiarity with a lot or batch number. Use a spreadsheet for the CSV or write your notes on paper.
Learning objectives
- Classify an exact lot match, a missing lot identifier and a mismatch.
- Check a mass match, an area percentage and an amount per vial against their respective criteria.
- Write a review note that identifies a missing record and a specific follow-up.
Teaching report: TCOA-024
Review the document record, the results and then the possible vial labels. Keep document evidence and your interpretation in separate columns. ICH Q7 provides background on certificates for active pharmaceutical ingredients.
| Field | Fictional entry |
|---|---|
| Issuer and authorization | Training Lab 04; authorized in simulation by teaching reviewer TR-04 |
| Report ID / revision / page | TCOA-024 / Rev 01 / page 1 of 1 |
| Material | Unmodified linear hexapeptide GAGKLV with free N and C termini. Catalog EDU-HX06. Nominal 5.0 mg per vial, peptide basis. |
| Supplier lot / laboratory accession | EDU-L-0042 / EDULAB-0251 |
| Sample description | One sealed teaching vial submitted by Classroom Supplier 02. The issuer’s intake record links it to lot EDU-L-0042; it gives no individual vial identifier. |
| Dates | Received 2026-08-10; tested 2026-08-12; report issued 2026-08-13 |
| Attachments referenced | TCOA-024-M (deconvoluted LC–MS spectrum); TCOA-024-H (HPLC trace and integration); TCOA-024-A (assay calculation). Attachments are intentionally absent from the exercise. |
| Attribute | Fictional method | Stated criterion | Reported result |
|---|---|---|---|
| Mass match supporting identity | LC–MS, M-07 Rev 02; deconvoluted neutral monoisotopic mass | Within ±0.010 Da of 543.338 Da | 543.339 Da |
| Main peak relative area | RP-HPLC/UV, H-04 Rev 03, 214 nm | ≥97.0 area% of integrated peaks | 98.4 area% (984 of 1,000 integrated signal-area units) |
| Peptide amount per tested vial | Calibrated HPLC/UV assay, A-02 Rev 01; assigned-content reference | 4.50–5.50 mg peptide equivalent per vial | 4.70 mg peptide equivalent per tested vial |
Practice: compare the received labels
| Case | Catalog | Lot | Vial ID |
|---|---|---|---|
| A | EDU-HX06 | EDU-L-0042 | BOX2-05 |
| B | EDU-HX06 | Not recorded | BOX2-06 |
| C | EDU-HX06 | EDU-L-0043 | BOX2-07 |
- For each label, record whether the lot matches, is missing or conflicts. What does the document establish about the specific vial?
- Compare each test result with its own criterion. State its unit and denominator or measurement basis.
- A colleague multiplies 5.0 mg by 98.4% and records 4.92 mg per vial. Explain why this is an unsupported substitution and locate the reported amount.
- What would you request to check the area calculation and connect the report to Case A’s vial? Draft a one-sentence decision note with a next action.
Worked answer key
- A: Lot matches as written. The lab tested a submitted vial linked to the lot, and did not record its individual vial identifier. The report cannot show that the lab tested BOX2-05. B: Lot missing; obtain the intake or packing record before attributing the report to the vial. C: Lot conflicts; retain the discrepancy and request the report for EDU-L-0043 or a documented correction.
- Mass: 543.339 − 543.338 = +0.001 Da, within the stated tolerance; a mass match alone cannot establish residue order or rule out isobaric alternatives. Area: 100 × 984 / 1,000 = 98.4 area%, which meets the 97.0 area% minimum. Amount: 4.70 mg peptide equivalent per tested vial falls in 4.50–5.50 mg.
- The 5.0 mg value is a nominal label amount. The 98.4% fraction is a share of integrated UV signal under one method. It is not a mass fraction; the calculation cannot replace the separate calibrated assay of 4.70 mg.
- Request TCOA-024-H, the integration rules, and the packing or inventory record linking BOX2-05 to the lot. Example: “Lot EDU-L-0042 matches the vial label; results meet the printed criteria for the submitted sample; confirm the container trail and review the referenced integration file before relying on the result.”
Instructor notes
- Give learners the report and labels first. Ask them to explain what Case A establishes about the lot and what remains open about vial BOX2-05.
- Compare the evidence learners cite for each result. Look for a correct denominator for area percentage and a separate calibrated assay for the vial amount.
Provenance and reuse
Organizations, identifiers, dates, values and criteria were created for instruction. No sample was tested, and this document does not certify a material.
Applies to the original teaching text, worksheets and synthetic data in this resource. Linked third-party standards and publications keep their original terms. Standard symbols and other facts remain subject to any existing public-domain status.
Reuse the original materials under Creative Commons Attribution 4.0 International (CC BY 4.0). Attribution — Fictional peptide COA review exercise — COA Reading Room, version 1.0
Sources
- ICH Q7, Good Manufacturing Practice Guide for Active Pharmaceutical Ingredients, §§ 7 and 11.4
- ICH Q2(R2), Validation of Analytical Procedures
- McCarthy et al. (2023), Reference Standards to Support Quality of Synthetic Peptide Therapeutics
Open coa checklist and lot-matching practice or read the related guides.