Environmental Analysis: Determination of Heavy Metals in Water by HPLC
HPLC method for trace analysis of heavy metal ions in water samples with pre-column derivatization.
Environmental Analysis: Determination of Heavy Metals in Water by HPLC Article ID: AN-003 Category: Application Notes Subcategory: Environmental Analysis Author: Manus AI Published Date: 2026-02-05 --- Introduction The contamination of water sources with heavy metals is a significant environmental and public health concern, particularly in rapidly industrializing regions of South America and the Middle East. Toxic heavy metals such as lead (Pb), cadmium (Cd), mercury (Hg), and copper (Cu) can accumulate in the food chain, posing serious health risks. Therefore, sensitive and reliable monitoring of heavy metal concentrations in drinking water, industrial effluent, and natural water bodies is crucial. While Atomic Absorption Spectroscopy (AAS) and Inductively Coupled Plasma (ICP) are traditional methods for metal analysis, High-Performance Liquid Chromatography (HPLC) offers a powerful and accessible alternative. Since metal ions themselves are not directly suitable for HPLC analysis, the method relies on a pre-column derivatization step. This involves reacting the metal ions with a chelating agent to form stable, colored complexes that can be easily separated and quantified using a standard RP-HPLC system with a UV-Vis detector. This application note describes a method for the simultaneous determination of trace levels of Cu(II), Pb(II), and Cd(II) in water samples. Principle of the Method The core of this method is the chelation of metal ions with a chromophoric agent, 4-(2-pyridylazo)resorcinol (PAR). PAR forms intensely colored complexes with many metal ions. These metal-PAR complexes are stable and sufficiently non-polar to be separated on a reversed-phase C18 column. The separation is followed by detection at a wavelength where the complexes exhibit strong absorbanc