Microfluidic device with controllable shunts peripheral to integrated photodiodes

Abstract

A microfluidic device having a probe for hybridization with a target nucleic acid sequence, a photodiode for detecting fluorescence emissions generated by hybridization of the probe in response to an excitation light, and, a shunt transistor between the photodiode anode and a voltage source, the shunt transistor being configured to remove carriers generated by absorption of photons of the excitation light in the photodiode, wherein, a peripheral edge of the photodiode and a peripheral edge of the shunt transistor contiguously abut each other.

Description

FIELD OF THE INVENTION[0001]The present invention relates to diagnostic devices that use microsystems technologies (MST). In particular, the invention relates to microfluidic and biochemical processing and analysis for molecular diagnostics.CO-PENDING APPLICATIONS[0002]The following applications have been filed by the Applicant which relate to the present application:GBS001USGBS002USGBS003USGBS005USGBS006USGSR001USGSR002USGAS001USGAS002USGAS003USGAS004USGAS006USGAS007US GAS008USGAS009USGAS010USGAS012USGAS013USGAS014US GAS015USGAS016USGAS017USGAS018USGAS020USGAS021US GAS022USGAS023US GAS024USGAS025US GAS026USGAS027USGAS028USGAS030USGAS031USGAS032US GAS033USGAS034USGAS035USGAS036USGAS037USGAS038US GAS039USGAS040US GAS041USGAS042US GAS043USGAS044USGAS045USGAS046USGAS047USGAS048USGAS049USGAS050USGAS054USGAS055US GAS056USGAS057USGAS058USGAS059USGAS060USGAS061USGAS062USGAS063US GAS065USGAS066US GAS067USGAS068US GAS069USGAS070US GAS080USGAS081USGAS082USGAS083USGAS084USGAS085US GAS086USGAS0...

AI Technical Summary

Benefits of technology

[0091]Photosensors with controllable shunts obviate the need for any wavelength dependent filter components, making the design inexpensive, small, and light. Shunts peripheral to the photodetectors have low resistance, increasing the signal-to-noise ratio and sensitivity.

Problems solved by technology

Insufficient stringency can result in a high degree of nonspecific binding.

Excessive stringency can lead to a failure of appropriate binding, which results in diminished sensitivity.

Despite the advantages that molecular diagnostic tests offer, the growth of this type of testing in the clinical laboratory has been slower than expected and remains a minor part of the practice of laboratory medicine.

This is primarily due to the complexity and costs associated with nucleic acid testing compared with tests based on methods not involving nucleic acids.

However, controlling fluid flow through the LOC device, adding reagents, controlling reaction conditions and so on necessitate bulky external plumbing and electronics.

Connecting a LOC device to these external devices effectively restricts the use of LOC devices for molecular diagnostics to the laboratory setting.

The cost of the external equipment and complexity of its operation precludes LOC-based molecular diagnostics as a practical option for point-of-care settings.

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