One way to separate, identify, and measure the different nutrients in a sample is through High-Performance Liquid Chromatography (HPLC). During the test, a tube is filled with a material that attracts, and holds onto, different components of a supplement. Liquid is then pumped, along with the separated components, through a column, whereby the solution interacts with its surroundings. These interactions will cause each component to flow at a different rate, and those speeds are then measured via a detector at the end of the column. The rate of flow for each component forms a type of fingerprint, identifying each one, and these are then evaluated against industry recognized standards.
To measure for concentration, the separated components are passed in front of a detector that will produce peaks on a chromatogram (a type of graph). These peaks indicate the amount of each component present, and are evaluated against industry recognized standards.