Understanding how peptide purity is tested is essential for evaluating research peptide quality. This guide explains the analytical methods used to verify peptide purity and ensure reliable research outcomes.
Why Purity Testing Matters
Peptide purity directly impacts research accuracy and reproducibility. Even small impurities can affect experimental results, making rigorous testing essential for quality assurance.
Primary Testing Methods
1. High-Performance Liquid Chromatography (HPLC)
HPLC is the gold standard for peptide purity analysis and the most widely used method in the industry.
How HPLC Works:
- Separates peptide components based on their chemical properties
- Measures the percentage of target peptide versus impurities
- Provides a chromatogram showing purity peaks
- Detects even trace contaminants
HPLC Results:
A high-quality research peptide should show:
- A single, sharp peak representing the target peptide
- Minimal or no additional peaks (impurities)
- Purity percentage ≥98% for research-grade peptides
Learn more about HPLC testing for peptides in our detailed guide.
2. Mass Spectrometry (MS)
Mass spectrometry confirms peptide identity by measuring molecular weight with extreme precision.
How MS Works:
- Ionizes the peptide sample
- Measures mass-to-charge ratio
- Confirms exact molecular weight
- Detects modifications or degradation
MS Results:
Mass spec data should show:
- Molecular weight matching the expected value
- Minimal mass variations
- No unexpected peaks indicating impurities
3. Amino Acid Analysis (AAA)
Amino acid analysis verifies peptide composition and sequence accuracy.
How AAA Works:
- Hydrolyzes the peptide into individual amino acids
- Quantifies each amino acid present
- Compares results to expected sequence
- Confirms peptide identity
When AAA is Used:
- For critical research applications
- To verify complex peptide sequences
- As a secondary confirmation method
4. Thin Layer Chromatography (TLC)
TLC is a simpler, cost-effective method for preliminary purity assessment.
How TLC Works:
- Separates compounds on a coated plate
- Visualizes peptide and impurities
- Provides quick qualitative results
Limitations:
TLC is less precise than HPLC and typically used only for initial screening, not final quality verification.
Understanding Your Certificate of Analysis (COA)
Every research peptide should include a COA documenting purity testing results.
What to Look For:
- HPLC Chromatogram: Visual representation of purity
- Purity Percentage: Should be ≥98% for research-grade
- Mass Spec Data: Confirms molecular weight
- Batch Number: Traceability for quality control
- Testing Date: Ensures recent analysis
Learn how to read and verify your COA for complete quality assurance.
Bio Peptides UK Testing Standards
All our research peptides undergo comprehensive testing:
- HPLC Analysis: Every batch tested for ≥98% + purity
- Mass Spectrometry: Molecular weight confirmation
- Third-Party Verification: Independent laboratory testing
- Full Documentation: Complete COA with every order
Explore our purity standards and commitment to quality.
Purity Grades Explained
| Purity Grade | Purity Range | Typical Use |
|---|---|---|
| Research Grade | ≥98% | Most research applications |
| High Purity | ≥95% | Preliminary screening |
| Ultra-High Purity | ≥99% | Critical studies requiring maximum accuracy |
Quality You Can Trust
At Bio Peptides UK, we maintain the highest testing standards to ensure every peptide meets rigorous quality criteria. Our comprehensive testing protocols guarantee reliable, reproducible research results.
Order Verified Research Peptides
Browse our complete range of HPLC-tested, COA-certified research peptides on our Buy Research Peptides Online (UK) page.
All products are for research use only.