This application note describes the method for measuring chromium in environmental waters by atomic absorption spectrometry using a Zeeman corrected graphite tube atomizer. This method does not require the formation of a metal complex or extraction into an organic solvent for preconcentration, but directly injects the water sample into the graphite tube, which can reduce the possibility of sample preparation and contamination.
The document details a method for measuring trace metal levels, specifically chromium, in environmental waters. It highlights that direct aspiration into a flame is often insufficient due to low levels, necessitating the use of graphite furnace techniques with background correction.
The study utilized an Agilent SpectrAA-30 Zeeman atomic absorption spectrometer equipped with a programmable sample dispenser and a chromium hollow cathode lamp. The method was validated using certified water samples from the US Environmental Protection Agency (USEPA) and the National Bureau of Standards (NBS), demonstrating good agreement between experimental results and quoted values.
The final atomization step reached a temperature of 2500 °C.
The sampler introduced a total volume of 8 µL for each analysis.