Flow-injection quantification of trace lead in water by on-line preconcentration-flame atomic absorption spectrometry

Flow-injection flame atomic absorption spectrometry (FLA-FAAS) with the slotted quartz tube has been applied to determine lead in water via on-line preconcentration with chelating resin. Water sample mixed with the pH buffer (pH 9.0) was pumped through a conical column packed with 200 mg poly(8-HQ-SO3H) chelate resin and the lead in water sample was absorbed and then eluted into the nebulizer of AAS with a soltted quartz tube using 0.5 mol/L HCl. A linear response from 5 mug/L to 200 mug/L and a detection limit of 1 mug/L were achieved. This system improved the sensitivity of Pb by a factor of 115 compared with conventional FAAS. The proposed method has been successfully applied to the direct measurement of lead in drinking water at a sampling frequency of 30/h.