Micro carbon paste electrode

Apart from UV detection, there are two other alternative detection methods for trace analysis of nitrite. A very sensitive detection method for nitrite is DC amperometry at +1.1 V on a carbon paste electrode. In this case, amperometry and suppressed conductivity detection can be applied simultaneously by directing the conductivity cell effluent through the amperometric celL Figiu-e 10.17 exemplifies this with a surfiice water sample that was injected imdiluted [26]. As can be seen firom this chromatogram, nitrite concentrations in the lowest micro-gram/Liter range can be detected without any problem. 

Mojica E-RE, Vidal JM, Pelegrina AB, Micro JRL (2007) Voltammetric determination of lead (11) ions at carbon paste electrode modified with banana tissue. J Appl Sci 7... 

Bismuth-film electrodes (BiFEs), consisting of a thin bismuth-film deposited on a suitable substrate, have been shown to offer comparable performance to MFEs in ASY heavy metals determination [17]. The remarkable stripping performance of BiFE can be due to the binary and multi-component fusing alloys formation of bismuth with metals like lead and cadmium [18]. Besides the attractive characteristics of BiFE, the low toxicity of bismuth makes it an alternative material to mercury in terms of trace-metal determination. Various substrates for bismuth-film formation are reported. Bismuth film was prepared by electrodeposition onto the micro disc by applying an in situ electroplating procedure [19]. Bismuth deposition onto gold [20], carbon paste [21], or glassy carbon [22-24] electrodes have been reported to display an... 

Besides silicon, other materials have also been used in micro fuel cells. Cha et al. [79] made micro-FF channels on SU8 sheets—a photosensitive polymer that is flexible, easy to fabricate, thin, and cheaper than silicon wafers. On top of fhe flow channels, for both the anode and cathode, a paste of carbon black and PTFE is deposited in order to form the actual diffusion layers of the fuel cell. Mifrovski, Elliott, and Nuzzo [80] used a gas-permeable elastomer, such as poly(dimethylsiloxane) (PDMS), as a diffusion layer (with platinum electrodes embedded in it) for liquid-electrolyte-based micro-PEM fuel cells. 

---