Page 187 - An Introduction to Analytical Atomic Spectrometry - L. Ebdon

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B.5.4 Discussion

1 Are there any particular problems associated with Cu determination by GFAAS?

2 If the sample was a seawater matrix would you anticipate any problems with the analysis?

3 What methods could you use to overcome matrix interferences?

B.5.5 Reference

1. Haswell, S. (Ed.) Atomic Absorption Spectrometry. Elsevier, New York, 1991.

B.6 Speciation of Arsenic Compounds by Ion-Exchange High-Performance Liquid
Chromatography with Hydride Generation Atomic Fluorescence Detection.

B.6.1 Objectives
Speciation of a solution of mixed arsenic standards; determine the limit of detection; observe and
explain the effects of pre-reduction.

B.6.2 Instrumentation and Reagents

B.6.2.1 High-performance Liquid Chromatography

Mobile phase: Solutions of 0.1 and 0.0001 potassium sulphate (K SO ) (Aristar, BDH) freshly
M
2
4
prepared and buffered to pH 10 with a few drops of ammonia solution (AnalaR, BDH).
Pump: HPLC reciprocating pump (Waters) with a Rheodyne switching valve.

Column: 300 mm x 4.6 mm i.d. column packed with Benson BA-X10 strong ion-exchange packing
material, placed in a water-bath at 58°C.

The solution of 0.0001 K SO should be pumped through the column at 0.5 ml min for 30 min to
-1
4
M
2
allow the column to equilibrate. After this time, raise the flow rate of the mobile phase to 1.2 ml min .
-1
A summary of the HPLC conditions is given in Table B.1.