Engineering and Architecture
Nanoscience, Materials and Chemical Engineering
Development of Low Cost Molecular Diagnostics Device
The widespread availability of cost effective diagnostic tools based on molecular detection (targeting nucleic acid sequences or mutations) is an important advance that technology can provide for the public good: early pathogen detection for food safety, preventive, personalized medicine, and environmental monitoring are all areas that can be revolutionised. The real challenge is to deliver these diagnostic tools as ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and robust, Equipment free and Deliverable to end-users) devices.
In recent years, significant strides have been made in this direction. Most of the solutions are based on the “lateral flow assay” (LFA) that is commonly applied in pregnancy tests. Although significant improvements have been proposed to make the response of LFA quantitative, they still suffer in this respect when narrow concentration range specifications are needed. There is only a handful of approaches that have solved this problem incorporating optical or electrochemical detectors at low cost. Still, the LFA concept does not permit flow control of the sample, and therefore integration is low (from sample extraction, preparation, to detection).
In this project we want to develop the ultimate ASSURED molecular diagnostics platform based on screen printing technology that can be produced at a cost (bill of materials) of less than € 1 and operated at power consumption of less than 100 mW, making it operable by normal batteries, portable communication devices or solar powered equipment. The device will process a sample without user intervention and will be based on isothermal amplification of DNA targets. Sample flow will be controlled by capillary action and low consumption electroactivated valves. Detection will be achieved in a reagentless manner by using primers of different complexity to achieve desired sensitivity and specificity. For signal amplification will be achieved by including primers modified with electrochemically responsive nanoparticles. Different detection methods such as DPV or impedance spectroscopy and amperometry will be evaluated to achieve sub-fM limit of detection. The total response time, from sample application to reading the result will be less than 30 minutes.
To achieve this objective, this PhD project should improve methods for screen printing fabrication, should incorporate in the device DNA separation, and should invent a scheme to maintain the temperature of operation constant at 40 C with minimal power consumption. Use of chemistry and electrochemistry will improve on the detection method.
At present, there is no device that can incorporate all these functions in an integrated fashion and at low cost. Although the project`s goal is applied, the solutions for some of the problems such as the real time DNA separation and the temperature control will require the application of fundamental physical principles and candidates will benefit from this dual approach to innovation.
37.5 hours a week
|This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 713679|