What each measurement can tell you

Identity

Mass spectrometry compares the measured mass of what’s in the vial with the mass expected for the labelled compound. The lab interprets that comparison and says how strong the match is.

A mass match alone can’t tell every isomer apart or confirm the full sequence. Identity says nothing about purity, quantity or safety.

Chromatographic purity

HPLC separates what’s in the sample into peaks. The purity figure is the share of the detector’s response that belongs to the main peak. It depends on what the method detects and how the peaks are integrated.

A peak-area percentage is not the percentage of the powder in the vial by mass. The report states which basis it uses.

Content

Content is how many milligrams of the compound are in the vial, measured against a reference standard. It’s separate from purity and from the total weight of powder.

Sample preparation, calibration, interference and uncertainty all affect this number, and the lab reports them with it.

Endotoxin and heavy metals

These are separate tests for separate questions. The heavy-metal panel we’re seeking covers lead, arsenic, cadmium and mercury. Availability, reporting limits and vial requirements depend on the lab.

Method first

Before we offer a test, the laboratory confirms the method sits inside its accredited scope, with its reference materials, quality controls and the people who review the result. Unfamiliar compounds and blends get a feasibility check.