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Biomedical subjects

A Bruno Frazier

Publications and source records attributed to A Bruno Frazier.

3 recordsLinked to original sources

Multi-layer plastic/glass microfluidic systems containing electrical and mechanical functionality.

This paper describes an approach for fabricating multi-layer microfluidic systems from a combination of glass and plastic materials. Methods and characterization results for the microfabrication technologies underlying the process flow are presented. The approach is used to fabricate and characterize multi-layer plastic/glass microfluidic systems containing electrical and mechanical functionality. Hot embossing, heat staking of plastics, injection molding, microstenciling of electrodes, and stereolithography were combined with conventional MEMS fabrication techniques to realize the multi-layer systems. The approach enabled the integration of multiple plastic/glass materials into a single monolithic system, provided a solution for the integration of electrical functionality throughout the system, provided a mechanism for the inclusion of microactuators such as micropumps/valves, and provided an interconnect technology for interfacing fluids and electrical components between the micro system and the macro world.

Biocompatible Materials↗

A microfabricated thermal field-flow fractionation system.

A microscale thermal field-flow fractionation (micro-TFFF) system has been designed, fabricated, and characterized. Motivation for miniaturization of TFFF systems was established by examining the geometrical scaling of the fundamental TFFF theory. Miniaturization of conventional macroscale TFFF systems was made possible through utilization of micromachining technologies. Fabrication of the micro-TFFF system was discussed in detail. The micro-TFFF system was characterized for plate height versus flow rate, single-component polystyrene retention, and multicomponent polystyrene separations. Retention, thermal diffusion coefficients, and maximum diameter-based selectivity values were extracted from separation data and found comparable with macroscale TFFF system results. Retention values ranged from 0.33 to 0.46. Thermal diffusion coefficients were between 3.0 x 10(-8) and 5.4 x 10(-8) cm2/s x K. The maximum diameter-based selectivity was 1.40.

Journal Article↗

Geometric scaling effects in electrical field flow fractionation. 2. Experimental results.

Geometric scaling of microelectrical field flow fractionation (micro-EFFF) systems is investigated experimentally and compared to theory and to macroscale EFFF systems. Experimental results are presented to demonstrate that the miniaturized system operates according to the scaling theory associated with the system. Demonstrated improvements in the channels include increased retention and resolution and decreased peak broadening, electrical time constants, relaxation time, power consumption, and sample size. Additionally, scaling effects related to the compression of separation zones in the miniaturized EFFF systems are discussed.

Electrodes↗