University of North Florida
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Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Andreas Manz

Abbrev:
Manz, A.
Other Names:
Address:
Zeneca/Smithkline Beecham Centre for Analytical Sciences, Imperial College, London, UK SW7 2AY
Phone:
NA
Fax:
+44-207-5945-833

Citations 5

"Micromachining Of Monocrystalline Silicon And Glass For Chemical Analysis Systems - A Look Into Next Century's Technology Or Just A Fashionable Craze?"
Trends Anal. Chem. 1991 Volume 10, Issue 5 Pages 144-149
A. Manz*, J. C. Fettinger, E. Verpoorte, H. Lüdi, H. M. Widmer and D. J. Harrison

Abstract: The theory and concepts behind the miniaturization of a total chemical analysis system are discussed. Micromachining is investigated and used in the construction of a flow injection analysis device and an optical detector cell.
Silicon Miniaturization

"Stacked Modules For Micro-flow Systems In Chemical Analysis: Concept And Studies Using An Enlarged Model"
Sens. Actuat. B 1993 Volume 17, Issue 1 Pages 19-25
J. C. Fettinger, A. Manz*, H. Lüdi and H. M. Widmer

Abstract: A valveless FIA system is described comprising a stacked series of 2 mm thick x 50 mm diameter polished Plexiglass elements. The elements have a 35 mm diameter ring of 11 or 12 evenly spaced 1 mm diameter holes with either a 1 cm, 10 cm or 20 cm central hole, a channel, a channel and central hole or no central hole, and are stacked to provide mixing T-pieces, mixing chambers etc. (diagrams given). The use of this modular system was demonstrated with the use of 2.5 mM C. I. Reactive Blue 2 (details given) for sample introduction and injection and was coupled to an optical detector. Samples retained 96-97% of their concentration and calibration graphs were linear with standard deviations of 1%.
Modeling Injection technique Apparatus

"Shah Convolution Differentiation Fourier Transform For Rear Analysis In Microchip Capillary Electrophoresis"
J. Chromatogr. A 2001 Volume 924, Issue 1-2 Pages 177-186
Yien C. Kwok and Andreas Manz

Abstract: This paper first reports the application of Shah convolution differentiation Fourier transform for rear analysis. Rear analysis eliminates the need to create a well-defined and reproducible sample plug, thus making the operation simpler. The number of solution reservoirs, for microchip capillary electrophoresis (CE), could be reduced from the usual four to three. Sample bias in CE could be avoided too. The separation channel was first filled with the fluorescent sample solution, and subsequently flushed out with the buffer. The rear of each analyte zone gives rise to its flight of sigmoid-shaped steps in the time-domain. The time-domain detector signal was first differentiated and then Fourier transform was performed. The Fourier transform results were represented in the form of a magnitude plot. It is proposed that this would be as equally applicable to other separation techniques (e.g., chromatography) and detection methods (e.g., absorption). (C) 2001 Elsevier Science BV All rights reserved.
Instrumentation Fourier transform

"Three-Dimensional Microfluidic Confinement For Efficient Sample Delivery To Biosensor Surfaces. Application To Immunoassays On Planar Optical Waveguides"
Anal. Chem. 2002 Volume 74, Issue 20 Pages 5243-5250
Oliver Hofmann, Guy Voirin, Philippe Niedermann and Andreas Manz

Abstract: A microchip-based flow confinement method for rapid delivery of small sample volumes to sensor surfaces is described. For flow confinement, a sample flow is joined with a perpendicular makeup flow of water or sample medium. Under laminar flow conditions, the makeup flow confines the sample into a thin layer above the sensing area and increases its velocity. This can benefit mass transport limited processes such as DNA hybridization or heterogeneous immunoassays. For proof of concept, this method was applied to a high-affinity immunoassay with excess capture antibody. Rabbit IgG was immobilized onto a silicon nitride waveguide. Cy5-labeled anti-rabbit IgG was hydrodynamically pumped over the immobilized zone through an attached 3D-PDMS flow cell with 20-µm-deep microchannels. The degree of confinement was adjusted through the volume flow rate of the confining flow. Evanescent field-based fluorescence detection enabled monitoring of the binding event. Assays were allowed to reach equilibrium to enable sensorgram normalization for inter-run comparison. The corresponding assay completion times could be reduced from 55 min for static drop conditions to 13 min for 25:1 flow confinement (ratio of confining to sample flow). For typical analytical applications, where equilibrium formation is not required, the faster response should translate to very short analysis times. Concurrently with the faster binding, sample consumption was reduced by 96% compared to conventional whole-channel sample delivery. Diffusional loss of analyte into the confining layer was identified as the main limitation of flow confinement, particularly for long sensing pads.

"On-line Monitoring Of Chromium(III) Using A Fast Micromachined Mixer/reactor And Chemiluminescence Detection"
Analyst 2000 Volume 125, Issue 4 Pages 677-683
Yi Xu, Fiona G. Bessoth, Jan C. T. Eijkel and Andreas Manz

Abstract: A fast micromachined mixer/reactor was employed in a continuous flow injection set-up for the direct detection of chromium(III) in aqueous samples by chemiluminescence (CL). With the device Cr(III) can be detected at a concentration of 10^-7 M and a linear calibration curve was obtained from 10^-6 to 10^-4 M Cr(III). In the continuous flow injection mode the system can perform fully automated detection with a reagent consumption of only 43.2 mL per day. In addition, a general theory is presented for the performance of diffusion-based mixer/reactor devices. This is the first report of the use of a micromachined device for the quantitative detection of Cr(III) with CL. Simple instrumentation, easy operation and low reagent consumption make this system a potential candidate for the in situ monitoring of Cr(III).