High-Performance Liquid Chromatography (HPLC) is the gold standard for purity verification in peptide research. Every Aurex Research product undergoes independent HPLC analysis by third-party laboratories. Understanding how HPLC works — and how to read the results — ensures you are conducting research with validated compounds.
What is HPLC?
HPLC separates molecules in a mixture based on their differential interaction with a stationary phase (column) and a mobile phase (solvent). Peptides elute from the column at different times based on their chemical properties. A UV detector measures absorbance at a specific wavelength (typically 214–220 nm for peptides), producing a chromatogram.
Reading a Chromatogram
The chromatogram is the visual output of HPLC analysis. Here is what to look for:
- The tallest peak represents your target peptide — this is the main compound
- Smaller peaks to the left and right are impurities (truncated sequences, byproducts)
- The area under each peak is proportional to the quantity of that compound
- Retention time (X-axis) identifies the peptide; peak area (Y-axis) quantifies it
- A clean chromatogram shows one dominant peak with minimal side peaks
What "≥99% Purity" Means
When Aurex reports ≥99% purity, this means the area under the target peptide peak constitutes at least 99% of the total integrated peak area. The remaining ≤1% consists primarily of truncated sequences (peptides missing one or more amino acids from incomplete synthesis) and minor synthesis byproducts. This is the industry standard for research-grade peptides.
Mass Spectrometry: Identity Confirmation
While HPLC confirms purity, mass spectrometry (MALDI-TOF or ESI-MS) confirms identity. MS measures the exact molecular weight of the peptide and compares it to the theoretical value calculated from the amino acid sequence. A match confirms the correct sequence was synthesized.
The Aurex 6-Step Process
- Solid-phase peptide synthesis (SPPS) in ISO-controlled environments
- HPLC purification achieving ≥99% target peptide purity
- Mass spectrometry verification of molecular weight
- Lyophilization for long-term stability
- Certificate of Analysis generation per batch
- Independent third-party laboratory verification
Your Certificate of Analysis includes the HPLC chromatogram, mass spectrometry data, batch number, purity percentage, and physical characteristics. Access your COA at aurex.bio/coa using your batch number.