Separation and preconcentration of ultratrace lead in biological organisms and its determination by graphite furnace atomic absorption spectrometry

• Published in: Talanta (Oxford) Vol. 43; no. 5; pp. 761 - 765
• Main Authors: Tang, Youwen, Chen, Bingren, Mo, Shengjun
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.1996; Oxford Elsevier
• Subjects: Analytical chemistry; Biological organisms; Chemistry; Exact sciences and technology; Graphite furnace atomic absorption spectrometry; Lead; Preconcentration; Separation; Spectrometric and optical methods; Preconcentration; Lead; Biological organisms; Graphite furnace atomic absorption spectrometry; Separation; Trace analysis; Chemical analysis; Graphite furnace; Thermoelectric atomization; Chitosan; Chemical enrichment; Atomic absorption spectrometry
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/0039-9140(95)01828-X

A biological organism (chitosan) was utilized to preconcentrate lead ions from tap water. This preconcentration was achieved by mixing 0.8 ml of chitosan slurry with 10–50 ml of lead-containing solution and subsequently separating by centrifugation. The chitosan paste was then dissolved in 1 ml of 0.2% nitric acid and analysed by graphite furnace atomic absorption spectrometry. The extraction efficiency can approach 100% in the pH range 4–10. The amount of chitosan used was not critical. The effect of some impurities was also investigated. If six samples were prepared simultaneously, the time needed to preconcentrate each sample was less than 3 min. Two different modes of standard addition (the standard lead solutions being added before and after preconcentration) were used for analysis of tap water samples, and the results obtained by the two modes were found to be quite consistent.