Purity & Testing
Understanding Mass Spectrometry
How laboratories confirm a compound is actually what the label says — by weighing its molecules.
5 min read
What mass spectrometry measures
Mass spectrometry (MS) determines the mass of molecules by ionizing them and measuring how those ions behave in an electromagnetic field. The result is a spectrum showing the mass-to-charge ratios detected in the sample.
Where HPLC answers 'how pure is this?', MS answers a different and equally fundamental question: 'is this the right compound at all?'
Identity confirmation in practice
Every peptide sequence has a precisely calculable molecular weight. When MS analysis of a sample returns that exact mass, the identity of the compound is confirmed. A mismatch — even by a few atomic mass units — indicates the material is not what it claims to be.
This is why SFVLAB documentation pairs HPLC purity data with MS identity confirmation: one verifies quality, the other verifies identity.
Reading an MS result on a COA
A COA will typically report the observed molecular weight alongside the theoretical value. The two should agree within the instrument's tolerance. Some reports include the spectrum itself, showing the detected ion series.
Research Use Only. This page is provided for scientific and educational purposes only. It is not medical advice, does not describe any approved therapy, and provides no dosing, administration, or treatment instructions for human use. SFVLAB products are not intended to diagnose, treat, cure, or prevent any disease and are not for human or veterinary use.
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- What Are Research Peptides? — Getting Started
- Understanding Research-Use-Only Products — Getting Started
- Research Peptide Terminology — Getting Started