3. Existing solutions

3.1 Different measurement principles

The various types of analyzers described below can be based on chemical, optical, electrochemical or biological measurement principles.

Whatever the principle, measurement is based on a system for recognizing the molecule of interest.

• In the case of chemical methods, complexation reactions are responsible for most measurements, and are generally characterized by the appearance of a color.

• Optical methods are based on light/matter interaction, highlighted by the modification of an electromagnetic beam and resulting in a spectrum. This spectrum may characterize a change due to the absorbance of part of the beam (UV, visible,...