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This review describes recent results regarding voltammetric and amperometric determination of submicromolar concentrations of various environmentally important biologically active organic substances using nontraditional types of electrodes either in batch analysis or in flow liquid systems (especially HPLC or FIA with electrochemical detection). Attention is paid to solid amalgam electrodes (environmentally friendly alternatives to mercury electrodes), to carbon paste electrodes with easily renewable surface, to boron doped diamond film electrodes with very low noise and broad potential window, and to inexpensive solid composite electrodes with high signal-to-noise ratio, compatibility with organic solvents and easy mechanical or electrochemical pretreatment. The review concentrates on our own results in the context of the general development in the filed.

This review describes our recent results regarding adsorptive stripping voltammetric determination of submicromolar and nanomolar concentrations of various environmentally important chemical carcinogens using both traditional (hanging mercury drop electrode, carbon paste electrode) and non-traditional types of electrodes (solid amalgam electrodes, glassy carbon paste electrodes, carbon ink film electrodes, solid composite electrodes). The review concentrates on our own results in the context of the general development in the filed.

Unsaturated wax esters (WEs) provided molecular adducts with C(3)H(5)N ([M + 55](+•)) in APCI sources in the presence of acetonitrile. CID MS/MS of [M + 55](+•) yielded fragments allowing the localization of double bond(s) in the hydrocarbon chains of the WEs. These fragments were formed by a cleavage on each side of the double bond. In methylene-interrupted polyunsaturated WEs, diagnostic fragments related to each double bond were detected; the most abundant were those corresponding to the cleavage of the C-C bond next to the first and the last double bond. To differentiate between those fragments differing in their structure or origin, a simple nomenclature based on α and ω ions has been introduced. Fragmentation of the α-type ions (fragments containing an ester bond) provided information on the occurrence of a double bond in the acid or alcohol part of the WEs. While no significant differences between the spectra of the WEs differing by cis/trans isomerism were found, the isomers were separated chromatographically. A data-dependent HPLC/APCI-MS(2) method for the comprehensive characterization of WEs in their complex mixtures has been developed and applied to natural mixtures of WEs isolated from jojoba oil and beeswax. More than 50 WE molecular species were completely identified, including the information on the acid and alcohol chain length and the position of the double bonds.

Abstract:The applicability of differential pulse voltammetry (DPV) and adsorptive stripping voltammetry (AdSV) at a non-toxic meniscus-modified silver solid amalgam electrode (m-AgSAE) for the determination of trace amounts of genotoxic substances was demonstrated on the determination of micromolar and submicromolar concentrations of 3-nitrofluoranthene using methanol -0.01 mol L -1 NaOH (9:1) mixture as a base electrolyte and of Ostazine Orange using 0.01 mol L -1 NaOH as a base electrolyte.

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