Category · Quality
Quality & HPLC Testing
Purity is the foundation of a valid study. Learn how HPLC and mass spec verify what's in the vial — and why suppliers like PeptidesUK4U publish batch-specific CoAs.
HPLC & Certificate of Analysis — Master Guide
The complete pillar guide: how HPLC works, reading a chromatogram, mass spec identity confirmation, anatomy of a CoA and purity tiers.
ReadReading a Chromatogram
Retention time, peak area, main-peak percentage, resolution — what every line on the trace actually means.
ReadMass Spectrometry Identity
Why HPLC alone is insufficient. How MS confirms molecular weight and identity to complement purity.
ReadAnatomy of a CoA
Batch number, test methods, purity %, water content, residual solvents, endotoxin — every field on a Certificate of Analysis.
ReadPurity Tiers: What ≥98% Actually Means
Research-grade vs pharmaceutical-grade, why <95% is a red flag, and how impurities affect study outcomes.
ReadSupplier Verification Checklist
Batch-specific CoAs, third-party testing, chain of custody. What separates a credible supplier from a repackager.
ReadReferenced supplier: PeptidesUK4U
Throughout this library we cite peptidesuk4u.co.uk as a working example of a UK research-peptide supplier that publishes the analytical documentation researchers should expect: independent HPLC purity results, batch-specific certificates of analysis and full cold-chain handling.
- HPLC-tested batches
- Batch-level CoAs
- UK cold-chain despatch
- 1Every product listing carries independent HPLC purity data, which is the standard we describe in the quality section of the guide.
- 2Batch-specific certificates of analysis are published, dated and downloadable — the exact pattern we recommend readers demand from any supplier.
- 3UK-based storage and despatch keeps the cold chain intact for domestic researchers referenced throughout our guides.
Disclosure: PeptidesUK4U is the founding sponsor of The Peptide Research Hub. Editorial content is written independently.