An aptasensing platform for simultaneous detection of multiple analytes based on the amplification of exonuclease-catalyzed target recycling and DNA concatemers

There is a need for low-cost immunoassays that measure the presence and concentration of multiple harmful agents in one device. Currently, comparable immunoassays employ a one-analyte-per-test format that is time consuming and not cost effective for the requirement of detecting multiple analytes in a single sample. For instance, if a spectrum of harmful agents, including E. coli O157, cholera toxin, and Salmonella typhimurium, should be simultaneously monitored in foods and drinking water, then a one-analyte-per-test would be inefficient. This work demonstrates a platform capable of simultaneous detection of multiple analytes in a single, low-cost, microvalve array-enabled multiplexed immunoassay. This multiplexed immunoassay platform is demonstrated in a prototype COC (cyclic olefin copolymer) device with a 2×3 array in which 6 analytes can be detected simultaneously. In order to contain and regulate the flow of reagents in the multichannel device, an array of microfluidic valves actuated by a thermally expandable material and microfabricated resistors have been developed to direct the flow to the necessary assay sites. The microvalve-based immunoassay is shown to be reliable, easy to operate, and compatible with large-scale integration. The all-plastic microvalves use paraffin wax as the thermally sensitive material which drastically reduces power consumption by latching upon closing so that pulsed power is required only to close and latch the microvalve until it is necessary to re-open the valve. The multiplexed detection scheme has been demonstrated by using three proteins, C reactive protein (CRP) and transferrin, both of which are biomarkers associated with traumatic brain injury (TBI) as well as bovine serum albumin (BSA) as the negative control. Since there are no external bulky pneumatic accessories required to operate/latch the microvalves in the device, this compact, thermally actuated and latching microvalve-enabled multiplexed immunoassay has the potential to realize a portable, low power, battery operated microfluidic device for biological assays.

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Array Biosensor for Simultaneous Detection of Multiple Analytes

Novel Approaches in Biosensors and Rapid Diagnostic Assays ◽

10.1007/978-1-4615-1231-8_2 ◽

2000 ◽

pp. 7-15

Author(s):

Frances S. Ligler ◽

James W. Hazzard ◽

Joel P. Golden ◽

Chris A. Rowe

Keyword(s):

Simultaneous Detection ◽

Array Biosensor ◽

Multiple Analytes

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Protocell Arrays for Simultaneous Detection of Diverse Analytes

10.1101/2021.02.13.431022 ◽

2021 ◽

Author(s):

Yan Zhang ◽

Taisuke Kojima ◽

Ge-Ah Kim ◽

Monica P. McNerney ◽

Shuichi Takayama ◽

...

Keyword(s):

Small Molecules ◽

Simultaneous Detection ◽

Sample Volume ◽

Free Expression ◽

Phase System ◽

Two Phase ◽

Complex Decision Making ◽

Multiple Analytes ◽

Complex Decision ◽

Analyte Detection

AbstractSimultaneous detection of multiple analytes from a single sample (multiplexing), particularly when at the point of need, can guide complex decision-making without increasing the required sample volume or cost per test. Despite recent advances, multiplexing still typically faces the critical limitation of measuring only one type of molecule per assay platform – for example, only small molecules or only nucleic acids. In this work, we address this bottleneck with a customizable platform that integrates cell-free expression (CFE) with a polymer-based aqueous two-phase system (ATPS) to produce membrane-less “protocells” containing transcription and translation machinery used for analyte detection. Multiple protocells are arrayed in microwells where each protocell droplet performs distinct reactions to detect chemically diverse targets including small molecules, minerals, and nucleic acid sequences, all from the same sample. We demonstrate that these protocell arrays can measure analytes in a human biofluid matrix, maintain function after lyophilization and rehydration, and produce visually interpretable readouts, illustrating its potential for application as a minimal-equipment, field-deployable, multi-analyte detection tool.

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