Microfluidic device with time delayed detection of fluorescence from hybridized probes

Abstract

A microfluidic device having a supporting substrate, a probe having a nucleic acid sequence for hybridization with a target nucleic acid sequence to form a probe-target hybrid, the probe-target hybrid being configured to generate a fluorescence signal in response to an excitation light, and, CMOS circuitry on the substrate, the CMOS circuitry having a photosensor for generating an output signal in response to the fluorescence signal, wherein, the CMOS circuitry is configured to trigger a time delay when the excitation light is deactivated before activating the photosensor.

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:GBS001USGBS002USGBS003USGBS005USGBS006USGSR001USGSR002USGAS001USGAS002USGAS003USGAS004USGAS006USGAS007USGAS008USGAS009USGAS010USGAS013USGAS014USGAS015USGAS016USGAS017US GAS018USGAS019US GAS020USGAS021US GAS022USGAS023US GAS024USGAS025US GAS026USGAS027US GAS028USGAS030US GAS031USGAS032USGAS033USGAS034US GAS035USGAS036US GAS037USGAS038US GAS039USGAS040US GAS041USGAS042USGAS043USGAS044USGAS045USGAS046US GAS047USGAS048USGAS049USGAS050USGAS054USGAS055USGAS056USGAS057US GAS058USGAS059USGAS060USGAS061USGAS062USGAS063US GAS065USGAS066US GAS067USGAS068US GAS069USGAS070USGAS080USGAS081USGAS082USGAS083USGAS084USGAS085US GAS086USGA...

AI Technical Summary

Benefits of technology

[0092]The time-delayed detection of fluorescence obviates the need for any wavelength dependent filter components, making the design inexpensive, small, and light.

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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