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Degree

PhD, University of Cincinnati, Engineering : Chemical Engineering, 2003.

Abstract

A comprehensive study of a micro Open Parallel Plate System (µOPPS) is presented. A detailed 3-dimensional computer model that solves a mass balance equation of a solute within the microchannel in the µOPPS was developed. The behavior of the µOPPS was modeled to determine optimal configuration and operating conditions. It was found that the microchannel width is the most important parameter that influences the performance of the µOPPS - microchannels with a width of 20 µm or less offer excellent performances. For deep channels, performance is essentially independent of channel depth. The capabilities of the µOPPS for preparative applications have also been studied. The µOPPS simulator was extended to model multicomponent systems and nonlinear behavior, and the potential for concentration of trace-species has been explored. By increasing the depth-to-width ratio of the µOPPS, it was possible to increase product-throughput significantly. Additionally, the utility of the µOPPS as a tool for obtaining equilibrium data for protein-salt systems has been investigated. Predictions of isotherm data were made by using the chromatographic-based H-Root Method (HRM). Simulations of the performance of the µOPPS for protein-salt systems in combination with the HRM allowed predicting isotherm coefficients with excellent accuracy, when the appropriate operating conditions were selected. An evaluation of the potential of combining µOPPS with Electrochemically Modulated Liquid Chromatography (EMLC) was also performed. In EMLC the retention of the solutes is modulated by applying an electric potential to a conductive stationary phase. The separation of two proteins by means of electrostatic interactions was simulated. It was found that excellent resolution and capacity factors can be achieved by utilizing narrow microchannels with higher applied potentials. The combination of the µOPPS with EMLC opens up the possibility of a new type of micro separation system with enormous potential for analytical and preparative applications. The study and development of the µOPPS device will offer important advantages for chromatographic separation processes. Future applications of this microsystem can be expected in analytical and preparative modes of chromatography, including design and scale-up of separation systems for pharmaceutical, biological and environmental applications.

Subject Headings

Chemistry, Analytical

Keywords

micro open parallel plate system; liquid chromatography; MEMS; microchromatograph; microseparator

Advisor

Dr. Neville G. Pinto

Pages

372p.

Document number: ucin1046966166
Permalink: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1046966166

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