Ion chromatography - Detection methods

The main detection systems used to separate inorganic ions in ion chromatography are presented in this second section. Although numerous detectors have been developed in recent years, the most common remains the conductivity meter, with or without suppression of the eluent's conductivity, due to its universality for ionic substances. The addition of an ion suppression device usually leads to improved ion detectibility. Gradually, however, other complementary and more specific detection systems have been introduced. These techniques are often combined with a post-column reactor to improve analyte detectability, or at least lower the detection threshold. These include electrochemical methods (amperometry, coulometry, polarography), spectrophotometric methods (refractometry, absorbance, fluorescence, chemiluminescence), and spectral coupling methods (flame or inductively coupled plasma atomic absorption and emission spectrophotometry, mass spectrometry). The latter offer unrivalled performance in terms of sensitivity and specificity. However, there is no such thing as universal detection, and all these techniques, whether specific to ion chromatography or not, appear to complement each other.

The article "Inorganic ion chromatography" is divided into two parts:

• [P 1 450] Stationary phases and separation methods ;

• [P 1 451] Detection methods.