- The current trend in analytical chemistry is to identify and quantify actual chemical species and not just determine the total amount of elements.
 + Different forms of the same element have completely different chemical and toxicological properties.
 +  Liquid Chromatography-Atomic Fluorescence Spectrometer was born, with its modular design,
 + Atomic fluorescence host and liquid chromatography unit are used separately,
 + which can not only perform morphological analysis of the elements, but also analyze the elements.
 + The elements have been measured overall.