Reading a Peptide Certificate of Analysis: Methods and Limits

What a certificate records

A certificate of analysis (COA) describes the analysis of an identified sample. Its value depends on whether the document identifies the material, batch, sample, test date, laboratory and methods. A report from a different batch is not a report for the item in front of you.

Check the relationship between the tested sample and the finished product. A report about a raw ingredient does not necessarily describe a filled pen or spray, its formulation, packaging or microbiological quality.

How to read analytical results

HPLC separates components under specified conditions. A reported peak-area percentage is a method-dependent analytical result, not the percentage of the entire package that is safe or effective. Different compounds may produce different detector responses, and a chromatogram may not identify every impurity.

Mass spectrometry can provide information about measured molecular mass. Assess it alongside other identity data and the stated method rather than treating one result as complete confirmation.

What a COA cannot establish

Chemical purity is not the same as sterility. Endotoxin testing and microbial testing address different questions; neither should be inferred from an HPLC percentage. No universal 98% or 99% cutoff establishes overall safety, approval or suitability.

Read the units, method, acceptance criteria and any limitations. If a document is unclear, ask for clarification rather than assuming a missing test was performed.

Scope of this reference

This is general reference information, not a dosing schedule, switching protocol, administration guide or recommendation to combine products. Published research and a compound name do not establish authorisation, safety or individual suitability of a separately supplied product. Clinical decisions require a qualified healthcare professional. 18+ only.

Peptide catalogue

Melanotan II — £40.00 — 10mg of Melanotan II; pre-filled injection pen
Somatropin (HGH) — £70.00 — Somatropin (Human Growth Hormone); pre-filled injection pen
Cagrilintide 10mg — £60.00 — 10mg of Cagrilintide; pre-filled injection pen
Epitathlon — £50.00 — 10mg of Epitathlon; pre-filled injection pen
PT-141 10mg — £40.00 — 10mg of PT-141; pre-filled injection pen
SLU-332 5mg — £65.00 — 5mg of SLU-332; pre-filled injection pen
CJC + Ipamorelin — £55.00 — 5mg CJC-1295 + 5mg Ipamorelin; pre-filled injection pen
5 Amino 1MQ 50mg — £60.00 — 50mg of 5 Amino 1MQ; pre-filled injection pen
SS-31 10mg — £40.00 — 10mg of SS-31; pre-filled injection pen
Semax 10mg — £40.00 — 10mg of Semax; nasal spray
Selank 10mg — £40.00 — 10mg of Selank; nasal spray
Ipamorelin 10mg — £40.00 — 10mg of Ipamorelin; pre-filled injection pen
Wolverine — £75.00 — 10mg BPC-157 + 10mg TB-500; pre-filled pen
MOTS-C 20mg — £80.00 — 20mg of MOTS-C; pre-filled injection pen
Tesamorelin 20mg — £110.00 — 20mg of Tesamorelin; pre-filled injection pen
NAD+ 1000mg — £125.00 — 1000mg of NAD+; pre-filled injection pen
GLO 70mg — £70.00 — 70mg of GLO; pre-filled injection pen
KLOW 80mg — £90.00 — 80mg of KLOW; pre-filled injection pen
BPC-157 10mg — £40.00 — 10mg of BPC-157; pre-filled injection pen
TB500 10mg — £50.00 — 10mg of TB500; pre-filled injection pen
Retatrutide — £200.00 — Retatrutide; pre-filled injection pen
Tirzepatide — £180.00 — Tirzepatide; pre-filled injection pen
MT2 10mg (NEXT DAY TAN) — £50.00 — 10mg of Melanotan2; pre-filled injection pen
GHK-CU 100mg — £60.00 — 100mg of GHK-CU; pre-filled injection pen

All products · Bundles · Articles

Peptide buying guides

Peptide pens vs vials — Product formats compared. Our catalogue contains pre-filled pens and Selank and Semax nasal sprays, not loose vials or powder.
Tirzepatide pricing and listing amounts — How to compare listed prices and amounts without assuming a dose or course length.
Retatrutide research and evidence limits — Distinguishing clinical-study findings from claims about a separately supplied product.
GLP-1 and metabolic peptides compared — Retatrutide, Tirzepatide, Cagrilintide and 5-Amino-1MQ compared by mechanism.
Are peptides legal in the UK? — Possession, supply rules, customs and what to check before ordering.
Tirzepatide safety information — Evidence limitations and why individual safety questions need a qualified healthcare professional.
Retatrutide safety information — Investigational status, evidence limitations and professional advice for medical concerns.
Retatrutide product information — Compound identity, product format and the limits of research evidence.
Tirzepatide product information — Ingredient identity, product formats and product-specific authorisation questions.
Melanotan II product information — Compound identity, listed format and questions about regulatory status.
PT-141 product information — Bremelanotide terminology, product identity and evidence limitations.
Tirzepatide and Retatrutide: research context — Receptor terminology and why ingredient comparisons do not select an individual treatment.
Tirzepatide and Semaglutide: research context — Ingredient differences and the distinction between a compound and an authorised medicine.
BPC-157: evidence and unit reference — Compound identity, mass-unit terminology and limits of clinical evidence.
Cagrilintide product information — Amylin-analogue terminology, format and research context.
NAD+ product information — Coenzyme identity and the distinction between biological roles and product benefits.
GHK-Cu product information — Copper-complex identity, product format and evidence limitations.
TB-500 product information — Thymosin beta-4 terminology and the importance of product identity.
5-Amino-1MQ product information — Small-molecule identity, the listed 50mg amount and research context.
Pre-filled pen format information — Product format terminology; device questions require product-specific professional guidance.
Missed-dose questions and professional advice — Why missed-dose decisions need product-specific advice from a qualified healthcare professional.
Travelling with product pens — Check destination rules and product-specific documentation rather than assuming universal travel permissions.
Product storage information — Why storage conditions must come from verified product-specific documentation.
Peptide unit reference — Educational mass equivalents between grams, milligrams and micrograms. No dosing or administration advice.
Dose terminology and professional advice — Understanding terminology does not establish an individual dosing schedule.