Devices and methods for the performance of miniaturized in vitro amplification assays

Abstract

This invention relates to methods and apparatus for performing microanalytic and microsynthetic analyses and procedures. The invention provides a microsystem platform and a micromanipulation device for manipulating the platform that utilizes the centripetal force resulting from rotation of the platform to motivate fluid movement through microchannels. The invention specifically provides devices and methods for performing miniaturized in vitro amplification assays such as the polymerase chain reaction. Methods specific for the apparatus of the invention for performing PCR are provided.

Description

[0001] This application claims priority to U.S. Provisional Application Ser. No. 60 / 140,477, filed Jun. 22, 1999, the disclosure of which is explicitly incorporated by reference herein.1. FIELD OF THE INVENTION[0002] This invention relates to methods and apparatus for performing microanalytic and microsynthetic analyses and procedures. In particular, the invention relates to microminiaturization of genetic, biochemical and bioanalytic processes. Specifically, the present invention provides devices and methods for the performance of integrated and miniaturized sample preparation, nucleic acid amplification, and nucleic acid detection assays. These assays may be performed for a variety of purposes, including but not limited to forensics, life sciences research, and clinical and molecular diagnostics. The invention may be used on a variety of liquid samples of interest, including bacterial and cell cultures as well as whole blood and processed tissues. Methods for performing any of a w...

AI Technical Summary

Benefits of technology

[0023] A preferred embodiment of the platforms of the invention is a platen that rotates with the microfluidics disk. The platen is most preferably a printed circuit board comprising resistive heating elements, thermoelectric (Peltier) elements, temperature sensors, assay optics and microprocessor and other electronic components. Electrical communication between a rotating platen and stationary power sources, motor controllers, temperature controllers, and computers is most preferably accomplished through a slip-ring assembly. By mounting the microfluidic disk on the platen and rotating both disk and platen together, the distribution and flow rate of fluid throughout the microfluidic structures as well as the temperature of fluid within localized regions of the microfluidics disc can be controlled.

[0039] The invention disclosed herein is flexible as to sample and source, being capable of isolating nucleic acid from bacteria, whole animal blood, tissues and cellular sources. It is rapid, being about 50% more rapid than existing "automated" nucleic acid preparatory methods. The nucleic acid output of the system is of a quality higher than or equal to methods known in the art. The system is simple and easy to use, robust because it is not dependent on operator variability. In addition, the platforms and systems disclosed are self-contained and integrated, thereby minimizing both operator handling and error.

Problems solved by technology

Filtration methods can produce a plasmid DNA solution, but the solutions required to solvate DNA are usually inappropriate for the desired final application of the DNA.

The technologies required for these steps include pipetting, pumping, filtration, washing, and centrifugation, requiring an expensive suite of devices and skilled operators thereof.

One drawback of the synthetic microchips disclosed in the prior art for performing PCR and other temperature-dependent bioanalytic reactions has been the difficulty in designing systems for moving fluids on the microchips through channels and reservoirs having diameters in the 10-100 .mu.m range.

These disabilities of the prior art microchips limits the usefulness of these devices for miniaturizing and automating PCR and other bioanalytic processes.

This need is particularly acute for high throughput analyses, which are currently burdened by the high costs and complexity of automated, typically robotic, systems.

In particular, when an adhesive is used in the disk construction, there is a potential for contamination of the fluids by the adhesive material (or the plastic substrate or cover).

Interfering substances leaching from the adhesive, or adsorption and binding of substances by the adhesive, can interfere with chemical or biochemical reactions.

This can be more of a problem at elevated temperatures or if solvents, strong acids or bases are required.

This mixing time may be reduced by mechanical stirring, for example, but stirring is difficult to obtain in fluids confined in small structures because the flow of the fluid is laminar and does not contain turbulent eddies that are known to promote mixing.

Images