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We present a simplified approach for the trace screening of toxic heavy metals utilizing bismuth oxide screen printed electrodes. The use of bismuth oxide instead of toxic mercury films facilitates the reliable sensing of lead(II), cadmium(II) and zinc(II). A linear range over 5 to 150 mg L À1 with detection limits of 2.5 and 5 mg L À1 are readily observed for cadmium and lead in 0.1 M HCl, respectively. Conducting a simultaneous multi-elemental voltammetric detection of zinc, cadmium and lead in a higher pH medium (0.1 M sodium acetate solution) exhibited a linear range between 10 and 150 mg L À1 with detection limits of 5, 10 and 30 mg L À1 for cadmium, lead and zinc respectively. The sensor is greatly simplified over those recently reported such as bismuth nanoparticle modified electrodes and bismuth film coated screen printed electrodes. The scope of applications of this sensor with the inherent advances in electroanalysis coupled with the negliable toxicity of bismuth is extensive allowing high throughput electroanalysis.

The first example of a copper(II) oxide screen printed electrode is reported which is characterised with microscopy and explored towards the electrochemical sensing of glucose, maltose, sucrose and fructose. It is shown that the non-enzymatic electrochemical sensing of glucose with cyclic voltammetry and amperometry is possible with low micro-molar up to milli-molar glucose readily detectable which compares competitively with nano-catalyst modified electrodes. The sensing of glucose shows a modest selectivity over maltose and sucrose while fructose is not detectable. An additional benefit of this approach is that metal oxides with known oxidation states can be incorporated into the screen printed electrodes allowing one to identify exactly the origin of the observed electro-catalytic response which is difficult when utilising metal oxide modified electrodes formed via electro-deposition techniques which result in a mixture of metal oxides/oxidation states. These next generation screen printed electrochemical sensing platforms provide a simplification over previous copper oxide systems offering a novel fabrication route for the mass production of electro-catalytic sensors for analytical and forensic applications.

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