How can peak height or peak area show the concentration of a substance?

In chromatography, peak height and peak area serve as quantitative measures to determine the concentration of a substance within a sample.12

Quantitative Analysis

To determine the concentration of a component, analysts typically prepare a working curve by plotting the peak height or peak area of a series of known standards against their respective concentrations. Once this curve is established, the concentration of the unknown component can be determined by comparing its specific peak height or area to the working curve.2

Peak Area vs. Peak Height

• Peak Area: The area enclosed by a peak is proportional to the total amount of solute that produced it. Modern electronic integrators calculate this by summing signal intensities over the duration of the peak, often adjusting for the detector's response factor for that specific solute.1
• Peak Height: Peak heights are frequently used as a quantitative measure for narrow peaks where determining the area accurately is difficult.1

Because different solutes may elicit varying responses from a detector, response factors are often incorporated into calculations to ensure accuracy, especially when comparing different substances.13