PDMS microchips

Figure 4.6 PDMS microchip, (a) PDMS microchip with (E) a graphite-coated emitter tip, (S) reservoirs for sample, (SW) sample waste and (B) buffer, (b) Double-T injection cross of the PDMS-device (1) channel path and (2) buffer flow [8].

Ro, K. W., Lim, K., Hahn, J. H., PDMS Microchip for precolumn reaction and micellar electrokinetic chromatography of biogenic amines, in Ramsey, J. M., van den Berg, A. (Eds.), Micro Total Analysis Systems, Kluwer, Dordrecht,... 

An integrated poly(dimethylsiloxane), PDMS, microchip for SPE and CE followed by ESl/TOF MS has been developed and evaluated by Dahlin and coworkers [122]. The microchip (see Fig. 7) was fabricated in a two-level cross design with PDMS cast over steel wires. Following PDMS polymerization and removal of the wires, 50 pm... 

Fig. 7 (a) PDMS microchip device A sample inlet channel, B CE channel, C waste channel, (b) Instrument setup and the connection of the microchip to the ESI/TOF MS. Reproduced from [122]... 

Fig. 4.18. (a) Schematic of PDMS microchip used for on-chip chemiluminescence assay. Reagents are loaded into inlets 1 and 2 and are hydrodynamically pumped towards outlet three. Light is generated when the two reagents mix. For detection a P3HT PCBM photodetector is placed underneath the detection chamber of the microchip, (b) Responsivity of the organic photodetector and emission spectra of the chemiluminescence dyes (Prom [21] - Reproduced by permission of The Royal Society of Chemistry)... 

Zeng, H. L., Li, H. F., and Lin, J. M., Chiral separation of dansyl amino acids by PDMS microchip gel monolithic column electrochromatography with [gamma]-cyclodextrin bonded in polyacrylamide. 

Song Y-A et al (2010) Free-flow ztme electrophoresis of peptides and proteins in PDMS microchip fOT narrow pi range sample prefractionation coupled with mass spectrometry. Anal Chem 82(6) 2317-2325... 

PDMS has unique properties such as elastomeric, nontoxic, optically transparent down to 280 nm, and hydrophobic surface chemistry. However, due to the PDMS adsorption property of most of chemicals, it is a challenge to perform the monoliths in a PDMS channel. Lin s group [13] fabricated polyacrylamide (PAA) gel monolithic column in a PDMS microchip for chiral separation in p-CEC. The PDMS microchannel was first pretreated with 3-(trimethoxysilyl) propyl methaciylate, and the chiral selector, y-cyclodextrin (y-CD), was immobilized firmly into the PAA gel in the nficrochannel. The key to... 

Open-channel titania and alumina-based PDMS microchip Trypsin Covalent linking Covalent immobilization of trypsin using activation reagent l-ethyl-3-(3-dimethyl aniinopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS) Fast flow rate of 3.5 pl/min enabled protein digestion for 5 s Innovative feature performing on-hne protein analysis by embedded stainless steel tubing electrode [78]... 

Microsphere-packed PDMS microchip Trypsin Covalent linking Crafted trypsin magnetic beads served as a matrix for digestion of recombinant human growth hormone for 4 min [84]... 

PDMS microchip with Y junction at the inlet, continuous flow operation... 

PDMS microchip with enzyme trapped in the PDMS cross-linked matrix... 

PDMS microchip supplemented with pyrogenic silicic acid as a filler and for providing hydroxy groups for surface chemistry... 

PDMS microchip 12 mm long trench structure containing 12 channels... 

Fig. 21.1 (a) Microfabrication of glass microchips. (Adapted from reference (10)). (b) Microfabrication of PDMS microchips. (Adapted frmn reference (12))... 

A particular example of polymer machining of great significance is the PDMS microchip. PDMS is a widely used polymer substrate for soft lithography-based microfabrication and nowadays has a relevant role in the miniaturization scene not only as microchip material but as ideal material to build lab-on-a-chip systems (soft lithography). Apart of the features described before, the major advantage of this material is the ability of rapid prototyping of complex structures. 

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