A DNA origami nanosensor based point of care device

In the context of the NCCR subproject "DNA Origami-based Sensor for the Multiplex Detection of mRNA in Cancer" within Module 1, we have developed a portable fluorescence microscope that operates using a
smartphone. This device is designed to detect the fluorescence of DNA origami biosensors. By combining the DNA origami biosensor with the portable microscope, we can create a comprehensive point-of-care
device that can be utilized in remote areas.

Our lab has successfully developed a prototype of a smartphone-based, portable fluorescence microscope capable of directly detecting a single fluorescent molecule without relying on additional enhancement elements such as optical antennas_. Thanks to the smartphone's color camera, this device has the potential for multiplex detection. We aim to demonstrate its capabilities for diagnostics and !T!Ultiplex sensing while enhancing user accessibility by ensuring stability in various conditions and minimizing the number of operational steps required.

To further improve performance, we plan to replace the smartphone camera with a fixed camera, thereby reducing the influence of variations in camera sensor quality and app performance. Subsequently, we will replace the laser module to enable testing of another excitation wavelength and assess the potential for multiplexed sensing. The portability of this microscope allows for use in remote areas where laboratory access is limited or nonexistent. Additionally, the fluorescence readout is applicable not only to detecting DNA origami biosensors but also for various bioassays.

This work is in collaboration with the University of Los Andes in Colombia, which is developing a bioassay for detecting malaria parasites that is compatible with portable microscopes.

The primary objective is to upgrade the portable microscope with a fixed camera·, improving its stability and accessibility for use by non-professional end-users who require minimal training. The fixed camera should ensure similar image quality to that of the current prototype. For this purpose, we will purchase optical components, various fixed cameras to test, and electronic components to transmit wireless data from the external camera to a smartphone.

The second objective is to demonstrate the compatibility of the device with at least one bioassay. The idea is to combine the portable microscope with the bioassay for detecting the Malaria parasite, currently being developed at the University of Los Andes in Colombia. It may be necessary to adapt the microscope to the bioassay and to access samples to test with a living malaria parasite, where such samples can be challenging to access in Switzerland.

The primary application will be the use of a portable microscope as a point-of-care device when coupled with a bioassay. The aim is to sensitively and rapidly detect disease biomarkers in remote areas under various conditions and for individuals with limited training.