Guides for research peptide buyers
Practical guides on how research peptides are tested, documented, handled and sourced — written and reviewed by our quality team for lab and procurement professionals.
Quality & testing
How to Read a Peptide Certificate of Analysis (CoA)
A line-by-line guide to reading a research peptide CoA: batch details, HPLC purity, identity, peptide content vs purity, and the red flags that should make you ask questions.
Read guideHPLC Peptide Purity Testing Explained
How reverse-phase HPLC measures research peptide purity, how to read a chromatogram, which impurities it detects, and what HPLC alone cannot tell you.
Read guideHandling & storage
Peptide Reconstitution: Calculating Concentration for Lab Work
How to calculate the concentration of a reconstituted lyophilised peptide and the volume needed per aliquot, with worked examples, unit pitfalls and good laboratory practice.
Read guideStoring and Handling Lyophilised Research Peptides
Practical storage and handling guidance for lyophilised research peptides: long-term temperatures, moisture and light protection, receiving goods, and stability after reconstitution.
Read guideBuying wholesale
Compound guides
Educational content for research and procurement professionals. Peptide Direct supplies compounds for laboratory research only — not for human consumption, and nothing here is medical advice.