Chemical analysis micro

Concrete applications of micro reactors for chemical analysis, albeit so far not a core application, have been described [5]. Among other uses in chemical analysis, micro devices for gas chromatography, infrared spectroscopy, and photoacoustic detection are mentioned. 

One of the new trends in chemical analysis appeared in the last decade is that the miniaturization. It becomes apparent in the miniaturization of analytical devices, separation procedures, measuring tools, analyzing samples and as a consequent the term micro have appeared. Further development of this trend have led to transfer from the term micro to nano one (nanoparticles, nanofluides, nanoprobes, nanoelectrodes, nanotubes, nanoscale, nanobarcode, nanoelectrospray, nanoreactors, etc). Thereupon a nanoscale films produced by Langmuir-Blodgett (LB) technique are proposed for modifying of chemical sensors. 

Major drivers for using micro-channel chip systems for chemical analysis are low reagent consumption, low energy consumption, high reliability, good robustness also in the hands of personnel not trained in analytical chemistry, and low maintenance requirements [30]. 

N., WiDMER, H. M., p-TAS miniaturized total chemical analysis systems, in Proceedings of the Micro Total Analysis System Workshop, pp. 5-27 (Nov. 1994), Enschede, The Netherlands. 

Chemical analysis. Succinoglycan, purified by micro-filtration and dialysis, was hydrolysed in 0.5M sulphuric acid at a concentration of approximately 5mg/ml for 16 hours at 95 C. Sugars and acids were determined by HPLC using Biorad HPX-87 columns. No pretreatment was required for acids analysis - detection was by measurement of UV... 

Ecotoxicity assessment of water samples was carried out, in parallel to chemical analysis, using three standardized bioassays based on the micro-crustacean Daphnia magna, the algae Pseudokirchneriella subcapitata, and the bioluminescent bacteria Vibrio fischeri. 

Lu H, Schmidt MA, Jensen KF (2001) Photochemical Reactions and On-Line UV Detection in Microfabricated Reactors. Lab Chip 1 22-28 Manz A, Harrison DJ, Verpoorte EMJ, Fettinger JC, Ludi H, Widmer HM (1991) Miniaturization of Chemical-Analysis Systems - A Look into next Century Technology or just a Fashionable Craze. Chimia 45 103-105 McCreedy T (1999) Reducing the Risks of Synthesis. Chem Ind 15 588-590 McCreedy T (2000) Fabrication Techniques and Materials Commonly Used for the Production of Microreactors and Micro Total Analytical Systems. Trac Trends Anal Chem 19 396-401... 

Krtschil U, Hessel V, Kralisch D, Kreisel G, Ktipper M, Schenk R (2006) Cost analysis of a commercial manufacturing process of a fine chemical using micro process engineering. Chimia 60 611-617... 

A survey of the applications of lasers in micro- and macro-spectral analysis has been given by Gbrlich and Moenke-Blankenburgi 302) Their group in Jena has developed the technique of laser microprobing into a reliable and versatile tool for chemical analysis 302a). 

Rudnitskaya, A., Schmidtke, b. M., Delgadillo, b, begin. A., and ScoUary, G. (2009b). Study of the influence of micro-oxygenation and oak chip maceration on wine composition using an electronic tongue and chemical analysis. Anal. Chim. Acta 642(1-2), 235-245. 

Analyst 73, 67—73 1948) (Review of electrolytic methods of micro chemical analysis)... 

To provide sufficient material for chemical analysis and an extended battery of biological tests consisting of SaZmoneZZa/mammalian-micro-some assay, sister-chromatid exchange (SCE), and micronucleus (MN) induction in Chinese hamster ovary (CHO) cells (ii), it was necessary to modify and evaluate the XAD resin cartridge for sampling very large volumes (>1000 L) of raw and treated water. 

E. J. Maienthal National Bureau of Standards, Micro-chemical Analysis Section, Room B331 Chemistry, Washington, D. C. 20234... 

Alimarin, J. P., and M. N. Petrikova The Ultra-Micro Method of Chemical Analysis. II. The Electrolytic Separation. Zh. Analit. Khim. (Russ.) 5, 11 (1953) J. Anal. Chem. USSR (Engl. Transl.) 8, 11 (1953). 

FIA is a chemical analysis method based plug-wise injection into a carrier stream [114—116]. These plug samples can be further manipulated, e.g. by reaction to compounds better detectable by a detector. The sample consumption can be reduced via miniaturization however, then usually laminar-flow conditions are given so that micro mixers are needed which are efficient in that regime. 

A schematic diagram of the demonstrator chemical analysis system is given in Fig. 24. The MCB comprises three in/outlets, two micro-pumps, two flow sensors and an optical absorption detector module. The purpose is to measure chemical reaction products by detection of the (spectral) absorption intensity. Sample and reagent liquids are mixed in the appropriate amounts on-board (currently the actual mixing takes place during the propagation in channels) and the optical absorption is measured at the detector side. 

The electronic control circuitry is situated in two levels below the MCB layer with the modules. It is based on a microcontroller system for the micro liquid handling and the chemical analysis data. Implemented in the electrical circuitry are driving circuits for the micro pumps, sensing circuits for the flow sensors, optical absorption measurement circuitry, power management and communications using an RS232 interface. 

Fig.l. Setup of a simple micro total analysis system for chemical analysis... 

Microfluidic concepts can be used to develop an integrated total chemical analysis system (TAS) [40], which include sample preparation, separation, and detection. The microminiaturization of a TAS onto a monolithic structure produces a //-TAS that resembles a small sensor. The first /(-TAS was a micro-gas chromatograph (GC) fabricated on a 5-in. silicon wafer in 1979 by a group at Stanford University [41]. Since then, developments in micromachining has led to the development of microsensors, microreactors,... 

Manz,A., Verpoorte, E., Raymond, D.E., Effenhauser, C.S., Burggraf, N., Widmer, H.M., pTAS-miniaturized total chemical analysis system. Micro Total Analysis Systems 94, Proceedings of the pTAS 94 Workshop, University of Twente, Netherlands, 21-22 Nov. 1994, 1995, 5-27. 

Harrison, D.J., Fluri, K., Seiler, K., Fan, Z., Effenhauser, C.S., Manz, A., Micro-machining a miniaturized capillary electrophoresis-based chemical analysis system on a chip. Science 1993, 261, 895-897. 

Bohm, S., Greiner, K., Schlautmann, S., de Vries, S., van den Berg, A., A rapid vortex micromixer for studying high-speed chemical reactions. Micro Total Analysis Systems, Proceedings 5th pi AS Symposium, Monterey, CA, Oct. 21-25,2001, 25-27. 

Frye-Mason, G., Kottenstette, R.J., Heller, E.J., Matzke, C.M., Casalnuovo, S.A., Lewis, P.R., Manginell, R.P., Schubert, W.K., Hietala, V.M., Shul, R.J., Integrated chemical analysis systems for gas phase CW agent detection. Micro Total Analysis Systems 98, Proceedings pTAS 98 Workshop, Banff, Canada, 13-16 Oct. 1998, 477M81. 

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