After constructing the circuit for the detection system with the raw electrical components, I sought preliminary validation of the detection system to determine the feasibility of this design.
Preliminary Testing Setup:
I first set up one light sensor with two LEDs and an optical filter to test one detection unit. I then performed qPCR on 4 positive samples of DNA and 2 negative DNA samples. Afterwards, I performed two simple tests. First, I looked to see if the DNA could fluoresce. Secondly, I judged the specificity of the light sensor to determine if it is capable of detecting the small changes in the DNA's fluorescence.
Firstly, I determined that the DNA did indeed fluoresce when using the SYBR green fluorescent probe under a 480 nm LED. Secondly, I determined that the Cadmium Sulfide optical sensor could detect very small changes in the light intensity. This was accessed by observing a millivolt level of specificity when using this sensor in a voltage divider circuit under a variable light source. Lastly, I determined that I needed to purchase higher quality LEDs because the optical filters revealed that our current LEDs emit a range of wavelengths of light.