Reported Purity: How to Read the Number

What a reported HPLC purity percentage means, why methods matter, and which conclusions cannot be drawn from the number alone.

A reported result, not a universal property

The purity number shown on a product page is the reported HPLC result associated with the sourced compound. It should not be generalized to a different compound, a different production run, or a different analytical method.

Method context matters

Column chemistry, mobile phase, gradient, wavelength, integration choices, and sample preparation can affect an HPLC result. A percentage is more informative when considered with the underlying analytical report.

Purity is not identity

HPLC and mass spectrometry answer different questions. Pepta Labs therefore describes the available documentation as HPLC purity analysis plus mass-spectrometry identity confirmation.

Purity is not sterility or potency

A reported HPLC percentage does not establish sterility, endotoxin level, potency, vial fill quantity, pharmaceutical grade, or suitability for human or animal use. Those tests and uses are not claimed.

Request the available report by emailing support@peptalabs.com.