초록 ▼

A micromachined system for electrical field-flow fractionation of small test fluid samples is provided. The system includes a microchannel device comprising a first substrate having a planar inner surface with an electrode formed thereon. A second substrate having a planar inner surface with an elec

A micromachined system for electrical field-flow fractionation of small test fluid samples is provided. The system includes a microchannel device comprising a first substrate having a planar inner surface with an electrode formed thereon. A second substrate having a planar inner surface with an electrode formed thereon is positioned over the first substrate so that the respective electrodes face each other. An insulating intermediate layer is interposed between the first and second substrates. The intermediate layer is patterned to form opposing sidewalls of at least one microchannel, with the electrodes on the substrates defining opposing continuous boundaries along the length of the microchannel. Inlet and outlet ports are formed in one or both substrates for allowing fluid flow into and out of the microchannel. The microchannel device can be fabricated with single or multiple microchannels therein for processing single or multiple test fluids. During operation, a voltage differential is applied to the electrodes in order to induce an electric field across the microchannel. This separates particles of different types present in a fluid injected into the microchannel. The separated particles in the fluid can be collected or further processed as desired.

대표청구항 ▼

[ What is claimed and desired to be secured by United States Letters Patent is:] [1.] A microchannel device for electrical field-flow fractionation of a fluid, comprising:a first substrate having a substantially planar inner surface;a first electrically conductive layer on the inner surface of the f

[ What is claimed and desired to be secured by United States Letters Patent is:] [1.] A microchannel device for electrical field-flow fractionation of a fluid, comprising:a first substrate having a substantially planar inner surface;a first electrically conductive layer on the inner surface of the first substrate;a second substrate having a substantially planar inner surface and positioned over the first substrate;a second electrically conductive layer on the inner surface of the second substrate and facing the first electrically conductive layer;an intermediate layer interposed between the first substrate and the second substrate, the intermediate layer patterned so as to form opposing sidewalls of a microchannel, with the first and second electrically conductive layers defining opposing continuous boundaries along the length of the microchannel, wherein the microchannel is dimensioned such that the distance between the first and second electrically conductive layers along the length of the microchannel is less than about 100 .mu.m;an inlet port in the first or second substrate for allowing fluid flow into the microchannel;an outlet port in the first or second substrate for allowing fluid flow out of the microchannel; andone or more detectors in operative communication with the microchannel for analyzing a fluid in or from the microchannel, the detectors selected from one or more of the group consisting of electrical conductivity detectors and impedance detectors. [48.] An electrical field-flow fractionation process, comprising the steps of:providing a first microchannel device comprising:a first substrate having a substantially planar inner surface;at least one first electrode on the inner surface of the first substrate;a second substrate having a substantially planar inner surface and positioned over the first substrate;at least one second electrode on the inner surface of the second substrate and facing the first electrode; andan insulating intermediate layer interposed between the first substrate and the second substrate, the intermediate layer patterned so as to form opposing sidewalls of at least one microchannel, with the first and second electrodes defining opposing continuous boundaries along the length of the microchannel, wherein the microchannel is dimensioned such that the distance between the first and second electrodes along the length of the microchannel is less than about 100 .mu.m;applying a voltage differential to the first and second electrodes in order to induce an electric field across the microchannel;injecting a fluid through an inlet port in one of the substrates and into the microchannel;passing the fluid through the microchannel with the electric field therein in order to separate particles in the fluid; andmonitoring the separated particles in the fluid with a first detector selected from the group consisting of an electrical conductivity detector and an impedance detector.