Microfluidic templation

FIGURE 6.11 (a) Droplet microfluidic templating of micrometer-sized droplets... 

An alkaloid pain reliever, morphine, is an often abused drug. Chronoampero-metric MIP chemosensors have been devised for its determination [204]. In these chemosensors, a poly(3,4-ethylenedioxythiophene) (PEDOT) film was deposited by electropolymerization in ACN onto an ITO electrode in the presence of the morphine template to serve as the sensing element [204], Electrocatalytic current of morphine oxidation has been measured at 0.75 V vs AglAgCllKClsat (pH = 5.0) as the detection signal. A linear dependence of the measured steady-state current on the morphine concentration extended over the range of 0.1-1 mM with LOD for morphine of 0.2 mM. The chemosensor successfully discriminated morphine and its codeine analogue. Furthermore, a microfluidic MIP system combined with the chronoamperometric transduction has been devised for the determination of morphine [182] with appreciable LOD for morphine of 0.01 mM at a flow rate of 92.3 pL min-1 (Table 6). 

Imprinting into plastic materials can help to overcome two main disadvantages of silicon-based microfluidic systems expense of fabrication and brittleness of the material. Imprinting can be carried out at elevated temperatures [6,7] or at room temperature [8]. While heating of the plastic material can result in better feature aspect ratios, it is limited by the breaking of silicon templates during the cooling process due to the different thermal... 

There are many potential applications of such 3D polymer nanostructures. Multilayered structure with varied grating periods can be used as size-controlled filters in microfluidics to select and separate particles of different sizes. Another potential application is to fabricate periodic 3D polymer structures and infiltrate the polymer template with high refractive index inorganic... 

Fig. 10 Droplet microfluidics for microparticle synthesis, (a) Janus particle synthesis by coflowing two monomer streams. Reproduced with permission from [82]. (b) Channel geometry facilitated aspherical particles synthesis. Reproduced with permission from [111], (c) Multiple emulsion templated composite particles synthesis. Reproduced with permission from [112]...

Multiple PCR chambers have been fabricated on a single microfluidic chip and explored for high throughput PCRs [78-83]. An example of a multichamber micro-PCR device, the micro-DNA amplification and analysis device, (p-DAAD) consisted of 16p-DAADs in parallel with each p-DAAD consisting of four microreactors fabricated on a 4" silicon wafer (see Fig. 4). Multichamber micro-PCR devices [84] have been demonstrated for DNA amplifications of five gene sequences related to E. coli from three different DNA templates and detected by TaqMan chemistry with a limit of detection (LOD) of 0.4 copies of target DNA. 

Fig. 20 Representative nine-plex STR profiles of (a) 9,947A female and (b) 9,948 male standard DNA obtained with 100 copies of DNA template in the PCR chamber of an integrated microfluidic system. Reproduced from [258] with permission...

Fig. 3 Left Microfluidic chip for lEF/SDS-PAGE. Center Chip used for the 2D electrophoretic separation. The chip was made from a polycarbonate substrate from a Si template via hot embossing. Right Paths for the electrokinetic transfer of focused protein bands from the first (lEF) into the second (SDS-PAGE) dimension. Adapted with permission from Li et al. [79]...

C. Choi, H. Yi, S. Hwang, D. Weitz, and C. Lee, Microfluidic fabrication of complex-shaped microfibers by liquid template-aided multiphase microflow, Lab on a Chip, 11, 1477-1483, 2011. 

W.J., Keasling, J.D., and Howe, R.T. (2006) Microfluidic generation of tunable double emulsions for templated monodisperse silica particles. Proceedings of Micro-TAS Conference, Tokyo, Japan, 2006, p. 3. 

In situ IR spectroscopy is interesting for a broad range of technological applications, e.g., in (i) biomedicine and biochemistry, (ii) electrochemistry, (iii) catalyses, and (iv) microfluidic devices. In particular, it is relevant for the design of functional templates for drug release [5], studies of smart films and surfaces [11], characterization... 

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