Chemical vapour generation assisted by Cr³⁺/KCN coupled to atomic fluorescence spectrometry for ultrasensitive determination of cadmium in water and rice samples

Abstract

A methodology for cadmium determination at ultratrace levels based on chemical vapour generation (CVG) coupled to atomic fluorescence spectrometry (AFS) was developed. Cd volatile species were generated in a four...

Atomic spectrometry update – a review of advances in environmental analysis

“…The detection of Cd by HG-AFS was improved 66 by using 0.6 mM Cr 3+ and KCN as reduction catalysts to enhance Cd vapour generation. Detection by AFS instead of FAAS allowed the KCN concentration to be lowered from 0.1 to 0.01 M, thereby considerably reducing the background signal and the toxicity of the reagents.…”

“…A method optimised for ultratrace determination of Cd in water and rice by CVG-AFS involved 66 addition of Cr 3+ /KCN to enhance the generation of Cd volatile species and a laboratory-built non-dispersive AFS instrument containing a high intensity EDL, two types of flame atomiser and a PMT. The sensitivity achieved with the flame-in-gas-shield atomiser was almost twice that obtained with the miniature diffusion-flame atomiser resulting in a LOD of 0.42 ng L −1 .…”

Atomic spectrometry update: review of advances in the analysis of clinical and biological materials, foods and beverages

“…Three papers reported improved vapour generation methods for sample introduction in atomic fluorescence spectrometry. Štádlerová and co-workers 150 developed a method to determine ultratrace levels of Cd by means of FI-CVG-AFS, with an impressive LOD of 0.42 ng L −1 , that, depending on the matrix, may be better than those reported for other VG techniques coupled to AFS or ICP-MS. On the basis of their previous findings to improve the efficiency of CVG, the authors used a four-channel FI-CVG unit. This allowed separate introduction of the reductants (5% m/v NaBH 4 and 0.2 mol L −1 HCl), both at 1 mL min −1 , and the modifiers (0.6 mmol L −1 Cr 3+ , prepared from Cr(NO 3 ) 3 ·9H 2 O and 0.01 mol L −1 KCN) both at 0.5 mL min −1 .…”