Evaluation of Pb-Spec® for flow-injection solid-phase extraction preconcentration for the determination of trace lead in water and wine by flame atomic absorption spectrometry
Küçük Resim Yok
Tarih
2003
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Science Bv
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Two manifold designs were evaluated. Water samples and wine digests in 10% nitric acid were pumped through a column containing a commercially available resin (Pb-Spec(R)), an immobilized crown ether with a cavity size selective for Pb2+. The column was rinsed with 2% HNO3 and the eluent, 0.1 mol l(-1) ammonium oxalate was injected via a six-port rotary valve. The eluted lead was delivered to the flame atomic absorption spectrometer at 4.0 ml min(-1). The following flow-injection (FI) parameters were optimized: sample acidity and volume, loading and elution flow rates, and eluent composition and volume. The detection limit for the water samples, estimated from the noise on the signal obtained for 250 ml of 10 mug l(-1) loaded at 19.1 ml min(-1) was 1 mug l(-1). For 50 ml of wine digest loaded at 4 ml min(-1), the value was 3 mug l(-1). The roles of loading flow rate and sample volume were investigated in detail. The variation in retention efficiency with loading flow rate showed that the amount of lead retained (during a fixed loading time) increased with flow rate until the upper performance limit of the peristaltic pump was reached. The variation of detection limit with sample volume followed the expected hyperbolic relationship and showed that only small improvements in LOD were obtained for volumes greater than 50 ml. The method was evaluated through spike recovery for both water and wine. The lead contents of tap (0.24 mug l(-1)), pond (0.40 mug l(-1)), and river waters (not detected) were determined. The concentrations of lead in three Port wine samples ranged from not detected to 190 mug l(-1). No significant matrix suppression effects were observed. (C) 2003 Elsevier Science B.V. All rights reserved.
Açıklama
Anahtar Kelimeler
Flow-Injection, Solid-Phase Extraction, Lead, Preconcentration, Atomic Absorption Spectroscopy, Plasma-Mass Spectrometry, Online Preconcentration, Port-Wine, Sorbent Extraction, Isotope Ratios, Uv-Irradiation, Samples, System, Pretreatment, Speciation
Kaynak
Analytica Chimica Acta
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
485
Sayı
1
