Non-Fluidic Microdetection Device and Uses Thereof

Abstract

The present invention provides a microchip for performing electrophoresis with electrochemical means, such as by pulsed amperometric detection (PAD), for the separation and detection of underivatized carbohydrates, amino acids, sulfur-containing antibiotics, etc. The present methods permit the direct detection of amines, thiols, alcohols and carbohydrates and therefore is a useful technique for the development of electrochemical detection for microchip electrophoresis.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority to U.S. Provisional Patent Application No. 60 / 496,673, entitled “Direct Determination of Carbohydrates, Amino Acids and Antibiotics by Microchip Electrophoresis with Pulsed Amperometric Detection,” filed Aug. 21, 2003, and to PCT / US2004 / 021740, filed Jul. 8, 2004, and to U.S. Utility patent application Ser. No. 10 / 568,975, filed Sep. 12, 2006, the entire contents and disclosure of all of which is hereby incorporated by reference.BACKGROUND[0002]1. Field of Invention[0003]The present invention relates generally to electrophoresis, and more particularly to a microchip that performs electrophoresis, a method to produce a microchip with integrated electrodes, and a method for performing electrophoresis using a microchip with integrated electrodes.[0004]2. Related Art[0005]Microanalytical devices open up new possibilities for the miniaturization of conventional chemical and biochemical analysis systems. Since t...

AI Technical Summary

Benefits of technology

[0009]According to a third broad aspect of the invention, there is provided a method for performing electrophoresis. Electrophoresis is performed by attaching at least first conductive element and a second conducive element to a microchip having a biologic microfluid thereon, wherein the microchip comprises at least one main channel formed in a channel forming medium, the main channel containing at least one biologic microfluid; at least one detecting channel containing the first conductive element for performing electrochemical detecting, the detecting channel being formed in the channel forming medium and adjoining the main channel; and at least one reservoir containing the second conductive element for serving as a reference to the first conductive element, the reservoir being formed in the channel forming medium and containing biologic waste; and applying either continuous or pulsed amperometric detection to the microchip using the conductive elements to thereby cause biologic specimens within the biologic microfluid to migrate toward the first conductive element and, when in electrical contact with the first conductive element, to generate a measurable signal.

Problems solved by technology

However, the cost of optical instrumentation, the need for analyte derivatization, and the limited portability of LIF has led to the investigation of electrochemical detection (ECD), an attractive alternative for microchip devices, see Verpoorte, E., Electrophoresis 2002, 23, 677-712; Wang, J., Talanta 2002, 56, 223-231; Rossier, J., Reymond, F., Michel, P. E., Electrophesis 2002, 23, 858-867; Lacher, N. A., Garrison, K. E., Martin, R. S., Lunte, S. M., Electrophoresis 2001, 22, 2526-2536; Vandaveer, W. R. I. V., Pasas, S. A., Martin, R. S., Lunte, S. M., Electrophoresis 2002, 23, 3667-3677; and Wang, J., Trends in Anal. Chem. 2002, 21, 226-232, the entire contents and disclosures of which are hereby incorporated by reference.

However, when a constant potential is applied, the electrode may be fouled by the accumulation of adsorbed carbonaceous material, resulting in an unstable signal, see Fanguy, J. C., Henry, C. S., Analyst 2002, 127, 1021-1023; Garcia, G., Garcia, C. D., Ortiz, P. I., De Pauli, C. P., J. Electroanal. Chem. 2002, 519, 53-59, the entire contents and disclosures of which are hereby incorporated by reference.

Images