On-line pre-concentration and determination of lead in potable water by flow injection atomic absorption spectrometry

Abstract

A flow injection system incorporating a micro-column of activated alumina was used in conjunction with flame atomic absorption spectrometry for the pre-concentration and determination of lead in drinking waters. The analyte was deposited on the alumina micro-column {basic form of alumina) during the sampting stage and elution was effected by injection of nitric acid (250 yl, 2 M). The procedure was successfully applied to a range of water samples and the accuracy was assessed through recovery experiments, the analysis of a certified reference water and by independent analyses by inductively coupled plasma mass spectrometry. The limit of detection based on a sample volume of 25ml (sampling time-5min at 5mlmin-1) was 0.36 yg 1-1 and the relative standard deviations at 40 and 4pg 1-1 were 1.4 and 12%, respectively.

Atomic spectrometric detectors for flow-injection analysis

“…This manifold design, in common with others reported recently [83][84][85], allows the unretained sample components to flow through the nebulizer with the consequent risk of blockage in the case of samples with a high dissolved solid content. Two papers [84,85] described the use of activated basic alumina for the retention of lead (from a tap-water matrix) and cadmium (from a urine matrix).…”

“…Two papers [84,85] described the use of activated basic alumina for the retention of lead (from a tap-water matrix) and cadmium (from a urine matrix).…”

Resinas poliméricas para separação e pré-concentração de chumbo

“…A determinação quantitativa de metais-traço em amostras reais normalmente não é satisfatoriamente conduzida sem as etapas iniciais de separação e/ou pré-concentração, mesmo quando são aplicados métodos sensíveis, como a espectrometria de absorção atômica com geração de hidretos ou atomização eletrotérmica e a espectrometria de emissão atômica utilizando plasma 14 . A complexidade das matrizes analisadas leva à necessidade da inserção dessas etapas no processo analítico, que aumentam a concentração da espé-cie de interesse e eliminam interferências contidas na amostra, tornando-a mais facilmente analisável 15 .…”

In-Line Concentration on Chitosan and the Use of 2,2′-Dipyridyl-2-Pyridylhydrazone for the Flow-Injection Spectrophotometric Determination of Lead

“…[6][7][8][9] Besides, ion-exchange concentration/separation has proven to be an effective means for enhancing the sensitivity and improving the selectivity in analytical determinations.…”

“…5 Some of them have exploited C18 or ion-exchange resins followed by atomic absorption spectrometry. [6][7][8][9] Besides, ion-exchange concentration/separation has proven to be an effective means for enhancing the sensitivity and improving the selectivity in analytical determinations. 10 There has been increasingly interest concerning in-line concentration since 1980 10,11 , and several modifications have been proposed to improve its performance.…”