Analytical Sciences

Abstract − Analytical Sciences, 31(5), 383 (2015).

Automatic On-line Solid-phase Extraction–Electrothermal Atomic Absorption Spectrometry Exploiting Sequential Injection Analysis for Trace Vanadium, Cadmium and Lead Determination in Human Urine Samples
Georgia GIAKISIKLI,** Alejandro AYALA QUEZADA,* Junpei TANAKA,* Aristidis N. ANTHEMIDIS,** Hiroya MURAKAMI,* Norio TESHIMA,* and Tadao SAKAI*
*Department of Applied Chemistry, Aichi Institute of Technology, 1247 Yachigusa, Yakusa, Toyota 470-0392, Japan
**Laboratory of Analytical Chemistry, Department of Chemistry, Faculty of Science, Aristotle University, Thessaloniki, Greece
A fully automated sequential injection column preconcentration method for the on-line determination of trace vanadium, cadmium and lead in urine samples was successfully developed, utilizing electrothermal atomic absorption spectrometry (ETAAS). Polyamino-polycarboxylic acid chelating resin (Nobias chelate PA-1) packed into a handmade minicolumn was used as a sorbent material. Effective on-line retention of chelate complexes of analytes was achieved at pH 6.0, while the highest elution effectiveness was observed with 1.0 mol L−1 HNO3 in the reverse phase. Several analytical parameters, like the sample acidity, concentration and volume of the eluent as well as the loading/elution flow rates, have been studied, regarding the efficiency of the method, providing appropriate conditions for the analysis of real samples. For a 4.5 mL sample volume, the sampling frequency was 27 h−1. The detection limits were found to be 3.0, 0.06 and 2.0 ng L−1 for V(V), Cd(II) and Pb(II), respectively, with the relative standard deviations ranging between 1.9 – 3.7%. The accuracy of the proposed method was evaluated by analyzing a certified reference material (SeronormTM trace elements urine) and spiked urine samples.