Target Use Cases
Athletes in contact-based sports;
Elderly as every 4 seconds, a person above the age of 65 falls;
Military personnel with limited access to on-demand healthcare while in remote settings;
Emergency departments for rapid triage.
The primary goal of hardware is to detect flouresence at high resolution in a rapid manner. In order to accomplish this, four prototypes were subsequently developed and optimized.
Components
Imaging Module
a. Compare performance of mobile phone versus camera;
b. Determine external components needed (filter, lens, etc…)
c. Optimize camera properties, such as distance from LFA strip, orientation and zoom.
Case
a. Experiment with various dimensions (specifically height);
b. Ensure complete illumination;
c. Develop multiple prototypes using home-based tools;
d. Use CAD (Solidworks) to design a finalized prototype;
e. Assess the performance of the 3D model.
LED Lights
a. Evaluate number of LED lights needed;
b. Investigate various orientations;
c. Determine optimal orientation;
d. Assess distance between LED lights and LFA strip;
e. Explore the ability to achieve multi-wavelength detection, thus enabling multifunctional use of the device.
LFA Strip
a. Investigate the impact of external factors on quality of strip;
b. Vary dilution to assess sensitivity of the device.
Microcontroller
a. Minimize weight and space occupied by the microcontroller;
b. Investigate integration with external webcam;
c. Optimize data transmission rate and storage space by minimizing image size enabling higher rate of diagnosis.
The figures above depict images of the lateral flow assay strips collected using setup of prototype 1 suffering from low resolution and lack of flouresence.
Prototype 1
A pitch-dark case (composed of a cardboard box) encompassing a blue light filter, objective lens, LED strip and mobile phone were used. Experimentation was conducted with LED light directly above and directly below the LFA strip. Furthermore, a variety of LED colours (wavelengths) were tested to determine if they had any influence on excitation and emission of fluorescence, As illustrated in figure 3, this setup suffered certain limitations.
Prototype 2
A new prototype was created using a case with no lid enabling experimentation with distance (vertical and horizontal) between LED light, LFA strip and imaging source. In this prototype, the objective lens was eliminated, the LED light was altered to 680 and 800nm LED.
Prototype 3
This experimental setup strives to optimize distance between the LED light and LFA strip, orientation of the light and assess the efficacy of a webcam (as opposed to a mobile phone) with the infrared filter removed. Multiple images at different orientations were collected.
Prototype 4
This experimental setup strives to optimize distance between the LED light and LFA strip, orientation of the light and assess the efficacy of a webcam (as opposed to a mobile phone) with the infrared filter removed. Multiple images at different orientations were collected.
Prototype 5
Implementing the change from Arduino to Raspberry Pi allowed for a downsizing in the prototype as well as automated imaging. This increased reproducibility in the device overall.
Shorter wavelengths were tested for validation as illustrated in the following figures