Microfluidic parallel

Fig. 3.6 Schematic of the microfluidic parallel screening reactor system showing (a) reaction station, (b) spray station, and (c) imaging station.

Fig. 3.8 Schematic of the Microfluidic Parallel Screening Reactor System showing a single reaction/detection channel.

Mills, P. L., Mitchell, R. E., Wetzel, M. D., Schmidt, M. A., Jensen, K. F., Device level integration to form a parallel microfluidic reactor system, in Ramsey,... 

The last two restrictions can be overcome by using a microfluidic system where the sensing windows can be implemented parallel to each other and no interdistance is necessary. In that case, each sensing window can be as long as 28 mm, resulting in an improvement of the sensitivity by almost 1 order of magnitude. 

It is often desirable to immobilize different biomolecules on different sensing elements in close proximity on the same nanophotonic sensor in the development of a multiplexed sensor. This is the case in the example of parallel ID photonic crystal resonators described in Sect. 16.4. Cross-contamination of biomolecules must be avoided in order to preserve high specificity. We have found that a combination of parylene biopatteming and polydimethylsiloxane (PDMS) microfluidics is a convenient means to immobilized multiple biomolecules in close proximity without cross-contamination as shown in Fig. 16.8. Parylene biopatteming is first used to expose only the regions of highest optical intensity of the nanosensor for functionalization. Second, a set of PDMS microfluidics is applied to the parylene-pattemed nanophotonic sensor, and the biomolecules to be attached... 

A novel 24-channel HPLC by Nanostream called Veloce was introduced at PITTCON 04. The column cassette contains 24 parallel microbore columns. The eluted samples are detected by a 24-channel UV filter photometer. The advantage of such a system is that it allows one to work with multiple samples simultaneously. Other interesting systems for parallel HPLC were those introduced by Eksigent, based on microfluidic flow control, and Sepiatec GmbH, which allows the processing of 75 multiple-well plates. 

One way to ease any difficulties that may arise in fabricating a membrane, especially in design configurations that are not planar, is to go membraneless. Recent reports take advantage of the laminar flow innate to microfluidic reactors ° to develop membraneless fuel cells. The potential of the fuel cell is established at the boundary between parallel (channel) flows of the two fluids customarily compartmentalized in the fuel cell as fuel (anolyte) and oxidant (catholyte). Adapting prior redox fuel cell chemistry using a catholyte of V /V and an anolyte of Ferrigno et al. obtained 35 mA cmr at... 

Primary Screening Massively Parallel Microfluidic Reactor... 

Although the direct oxidation of ethane to acetic acid is of increasing interest as an alternative route to acetic acid synthesis because of low-cost feedstock, this process has not been commercialized because state-of-the-art catalyst systems do not have sufficient activity and/or selectivity to acetic acid. A two-week high-throughput scoping effort (primary screening only) was run on this chemistry. The workflow for this effort consisted of a wafer-based automated evaporative synthesis station and parallel microfluidic reactor primary screen. If this were to be continued further, secondary scale hardware, an evaporative synthesis workflow as described above and a 48-channel fixed-bed reactor for screening, would be used. 

Reaction conditions for the Massively Parallel Microfluidic Reactor were a feed of 6% C3H8, 7% NH3, 17% 02, and 70%, a reaction temperature of 420°C, and a residence time of 0.4 s. Integrated responses from the detection plate spots were non-linear and a calibration curve was generated from standards to quantify acrylonitrile content in the detection plate spots (Fig. 3.18). 

Figure 7.17 Schematic representation of microfluidic chemical reaction circuit used for parallel screening with in situ Click chemistry. Reproduced with permission from Wang, J., Sui, C., Mocharla, V.R, Lin, R.J., Phelps, M.E., Kolb, H.C. and Tseng, H.-R., Integrated microfluidics for parallel screening of an in situ click chemistry library. Angewandte Chemie International Edition 2006, 45, 5276-5281. Copyright Wiley-VCH Verlag GmbH.

The in situ experimental protocol using the microfluidic device allowed parallel screening and controls for 10 azide-acetylene fragment combinations per batch. Each screening campaign consisted of 32 individual reaction mixtures comprising the following format ... 

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