Determination of trace lead in the water by atomic absorption spectrometry combined with microextraction

The flame atomic absorption spectrometry(FAAS)was combined with the dispersive liquid-liquid microextraction(DLLME)for determination of trace lead in the water samples.The new system was employed for the microvolume nebulization of the non-flammable chlorinated organic extracts.Some effective parameters on the microextraction and the complex formation were selected and optimized,under the optimized conditions,the slope of the calibration curve after enrichment is 330 times as one before.The calibration curve is linear in range of 2.0～ 70 μg/L with a detection limit of 1.4 μg/L.The relative standard deviation(R.S.D.) for seven replicate measurements of 50 μg/L of lead is 0.2%.The percent recoveries of lead in tap,well and lake samples ranges from 104.4% to 109.6%.