An extremely rapid tool for continuous flow synthetic process optimisation is described. A microfluidic reaction system operating in continuous flow is used in conjunction with confocal Raman microscopy to afford rapid molecule synthesis and product quantitation. Accordingly, the approach allows for rapid reaction optimisation within a continuous flow system. Specifically, the catalytic oxidation of isopropyl alcohol (IPA) to acetone using tetra-N-propylammonium perruthanate (TPAP)/N-methylmorpholine N-oxide (NMO) in a radial interdigitated micromixer is studied as a model reaction system. The composition of the reaction effluent can be determined with great facility and information relating to catalyst/co-oxidant ratios, catalyst turnovers and reaction endpoints extracted. Specifically, variation of catalyst and co-oxidant volumetric flow rates between 0 and 50 microL min(-1) is used to vary reactant concentrations, define reaction residence times and control product conversions between 0 and 100%. The rapid nature of the system allows chemical information to be gathered and utilised on a sub-minute timescale.

Organic molecular semiconductors, such as pentacene (C22H14), is of great interest for potential application in thin-film organic field-effect transistors (OFETs). Novel scanning Raman microscopy was applied to the analysis of OFETs. Effective channel sizes in top-contact and bottom-contact OFETs were determined from scanning Raman spectra. The bottom-contact OFET showed a sharp change in Raman intensity at the gold/pentacene interface over a short distance while the top-contact OFET showed a gradual change in Raman intensity over a wide region. In the case of a gold electrode deposited on pentacene, the real channel size could be as small as half of the intended size. This resulted in the decrease in effective channel size and thus in the overestimation of the calculated mobility. The small channel length could be attributed to the presence of gold (composite) inside the channel in the top-contact OFET.

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The analysis of alcohol dehydrogenase (ADH) at low concentration using capillary electrophoresis is described. Several simple and effective ways to improve detection limits and sensitivity are investigated. These include large volume sample stacking, head column field amplified sample stacking, and sweeping. Results indicate that by using a combination of head-column field amplified sample stacking and sweeping, fluorescently labelled alcohol dehydrogenase can be pre-concentrated online by dissolving samples in water or other low conductivity matrices, and injecting into a high conductivity micellar buffer. The abrupt changes in conductivity cause narrowing of the analyte length and thus enhance the detection sensitivity. Combination of this approach with laser induced fluorescence detection yields a limit of detection of 5610 -13 M. Both qualitative and quantitative aspects of this method are investigated.