Quality Assurance

Our commitment to research-grade precision

At Mr. Peptide, quality is not an afterthought — it is the foundation of everything we do. Researchers depend on accurate, pure, and consistently characterized compounds. Our multi-stage quality control process ensures every product meets the highest standards before it reaches your laboratory.

Our Testing Protocol

1. High-Performance Liquid Chromatography (HPLC)

HPLC analysis is performed on every batch to determine purity percentage. Our threshold is ≥99% purity — batches that fall below this standard are rejected. HPLC testing separates the compound from potential impurities and provides a precise purity profile.

• Minimum purity threshold: ≥99.0%
• Analysis performed pre-release on every batch
• Results documented in batch-specific Certificate of Analysis
• Reverse-phase HPLC method used for peptide characterization

2. Mass Spectrometry (MS)

Mass spectrometry confirms the molecular identity of each peptide by verifying the correct molecular weight and fragmentation pattern. This rules out substitution with similar compounds and confirms the correct sequence.

• Electrospray ionization mass spectrometry (ESI-MS) used
• Confirms correct molecular weight within ±0.01 Da
• MS/MS fragmentation for sequence verification on select products

3. Amino Acid Analysis (AAA)

For complex peptides, amino acid analysis confirms the correct amino acid composition, verifying the ratio and presence of each amino acid in the peptide sequence.

4. Certificate of Analysis (COA)

Every product comes with a batch-specific Certificate of Analysis that includes:

• Product name and CAS number
• Batch number and production date
• HPLC purity result with chromatogram
• Mass spectrometry result with spectrum
• Appearance and physical characteristics
• Storage recommendations
• Testing laboratory information

5. Storage and Handling Standards

Products are stored in controlled conditions from production through shipping:

• Lyophilized peptides stored at -20°C or below until shipment
• Cold chain maintained during transit where required
• Pharmaceutical-grade containers with desiccant
• Light-protected amber vials for light-sensitive compounds
• Inert atmosphere packaging to prevent oxidation

Request a COA

COAs are available for any product. To request documentation for your order, email qa@mrpeptide.com with:

• Your order number
• The product name and batch number (found on your packaging)
• Your institution name (optional but helpful for bulk COA requests)