Flow injection electrochemical hydride generation atomic absorption spectrometry for the determination of cadmium in water samples

Cyanovanadate(III) complexes as novel additives for efficient generation of volatile cadmium species in complex samples prior to determinations by inductively coupled plasma mass spectrometry (ICP-MS)

“…It has been used for determination of trace levels of Cd by FAAS [4,6,9,11,14-17], ETAAS [7,10,12,20], ICP-AES [18], ICP-MS [19-21] and atomic fluorescence spectrometry (AFS) [5,13]. More recently, electrochemical hydride generation (ECHG) has been reported for determination by AAS, where volatile Cd species are generated by the reactions of Cd(II) with hydrogen atoms that are produced electrochemically on the cathode surface [22-24]. …”

“…Difficulties arise from a number of variables, such as poor efficiency, vapor instability and quenching or interferences in solution. It is well documented that the efficiency of Cd vapor generation is highly influenced by experimental settings and apparatus [4-24]. Transition metals and hydride forming elements, such as Cu(II), Fe(III), Ni(II), Pb(II) and Sn(II), have been reported to quench the efficiency regardless volatile Cd species are generated by chemical or electrochemical approaches [4-24].…”

“…It is well documented that the efficiency of Cd vapor generation is highly influenced by experimental settings and apparatus [4-24]. Transition metals and hydride forming elements, such as Cu(II), Fe(III), Ni(II), Pb(II) and Sn(II), have been reported to quench the efficiency regardless volatile Cd species are generated by chemical or electrochemical approaches [4-24]. Numerous attempts have been made to alleviate the interferences of the transition metal ions by modifying the reaction medium with surfactants and adding masking agents and catalyst elements.…”

“…Yet, an overview of the literature related to chemical approaches reveals that a great deal of problems occur in solution phase due to the quenching of the generation of gaseous Cd species (e.g., CdH 2 ) by certain transition metals [4-12]. Electrochemical vapor generation suffers from same interferences despite a different route of generation of the volatile species [23,24]. In a recent paper, we have utilized potassium hexacyanochromate(III) as a new additive for generation of Cd vapor and achieved an enhancement in sensitivity by more an order of magnitude in comparison to that achieved by conventional nebulization [26].…”

Solid-phase extraction with multiwalled carbon nanotubes prior to photochemical generation of cadmium coupled to high-resolution continuum source atomic absorption spectrometry

“…Arbab-Zavar et al studied electrochemical hydride generation system working in ow-injection mode for the determination of cadmium coupled to atomic absorption spectrometry. 16,17 In addition to chemical and electrolytic generation procedures photochemical (or UV-induced) vapour generation was used for cadmium determination. The technique is based on the generation of reducing radicals in the presence of low molecular weight organic acids upon UV irradiation with or without photocatalyst (or ultrasounds).…”