Fluidic array

Figure 4.15 Schematic of a micro fluidic array with programmable passive micro valves [71] (by courtesy of Kluwer Academic Publishers).

Another development towards the creation of ultra-fast DNA sequencing is the progress in designing and producing micro fluidic arrays. 

Figure 11.3. Fluidic flow directed assembly of NWs. (a,b) Schematic (a) and SEM image (b) of parallel NW arrays obtained by passing an NW solution through a channel on a substrate (c.d) Schematic (c) and SEM image (d) of a crossed NW matrix obtained by orthogonally changing the flow direction in a sequential flow alignment process. [Adapted from Ref. 49.]...

Figure 11.9. NW LED. (a) Crossed InP nanowire LED. (top) Three-dimensional (3D) plot of light intensity of the electroluminescence from a crossed NW LED. Light is only observed around the crossing region, (bottom) 3D atomic force microscope image of a crossed NW LED. (inset) Photoluminescence image of a crossed NW junction, (b-c) Multicolor nanoLED array, (b) Schematic of a tricolor nanoLED array assembled by crossing one n-GaN, n-CdS, and n-CdS NW with a p-Si NW. The array was obtained by fluidic assembly and photolithography with ca. 5- xm separation between NW emitters, (c) Normalized EL spectra obtained from the three elements. [Reprinted with permission from Ref. 59. Copyright 2005 Wiley-VCH Verlag.]...

Fig. 16.2 Nanoscale optofluidic sensor arrays (NOSA). (a) 3D illustration of a NOSA sensing element. It consists of a ID photonic crystal microcavity, which is evanescently coupled to a Si waveguide, (b) The electric field profile for the fundamental TE mode propagating through an air clad Si waveguide on SiOi. (c) SEM of a NOSA device array. It illustrates how this architecture is capable of two dimensional multiplexing, thus affording a large degree of parallelism, (d) Actual NOSA chip with an aligned PDMS fluidic layer on top. Reprinted from Ref. 37 with permission. 2008 Optical Society of America...

Fig. 6 (a) Schematic illustration of a flow cytometer used in a suspension array. The sample microspheres are hydrodynamically focused in a fluidic system and read-out by two laser beams. Laser 1 excites the encoding dyes and the fluorescence is detected at two wavelengths. Laser 2 is used to quantify the analyte, (b) Scheme of randomly ordered bead array concept. Beads are pooled and adsorbed into the etched wells of an optical fiber, (c) Scheme of randomly-ordered sedimentation array. A set of encoded microspheres is added to the analyte solution. Subsequent to binding of the analyte, microparticles sediment and assemble at the transparent bottom of a sample tube generating a randomly ordered array. This array is evaluated by microscope optics and a CCD-camera. Reproduced with permission from Refs. [85] and [101]. Copyright 1999, 2008 American Chemical Society... 

This dielectrophoretic droplet mixer, called a programmable fluidic processor, contains two rows of 32 pads for the electrodes these rows being at the upper and lower edges of the substrate and connected to the 8x8 electrode array in the center of the chip [99], The electrodes form a square matrix with an upper and lower half owing to the connectivity to the pads. The electrodes have a square shape. 

Zanzucchi, P. J., Cherukuri, S. C., McBride, S. E., Etching to form cross-over, non-intersecting channel networks for use in partitioned microelectronic and fluidic device arrays for clinical diagnostics and chemical synthesis, US 5681484, David Sarnoff Research Center, Princeton, NJ, 1995. 

Recent developments in sensor technology allow to create different integrated and miniaturized sensor arrays. Using microsystemtechnology fluidics can be added creating whole micro-analytical devices on chip. However, there are drawbacks involving inappropriate sensor function in media and production. Using sophisticated sensor construction and microfluidics such drawbacks can be overcome. In this chapter different sensor systems and whole micro-analytical devices are presented with emphasis on their applications. 

Modified microelectronic technology has created integrated and miniaturized sensor arrays. Additionally, microsystem technology allows to form whole microanalytical systems with integrated fluidics. 

Yan, K.Y., Smith, R.L., Collins, S.D., Fluidic microchannel arrays for the electrophoretic separation and detection of bioanalytes using electrochemilumines-cence. Biomed. Microdevices 2000, 2(3), 221-229. 

Sohn, Y.-S., Goodey, A.P., Anslyn, E.V., McDevitt, J.T., Shear, J.B., Neikirk, D.P., Development of a micromachined fluidic structure for a biological and chemical sensor array. Micro Total Analysis Systems, Proceedings 5th TTAS Symposium, Monterey, CA, Oct. 21-25, 2001, 177-178. 

Yun, K.S., Yoon, E., A micro/nano-fluidic chip-based micro-well array for high-throughput cell analysis and drug screening. Micro Total Analysis Systems 2003, Proceedings 7th pTAS Symposium, Squaw Valley, CA, Oct. 5-9, 2003, 861-864. 

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