Overview of the Original Diagnosis System
To test patients for the disease-associated SNP, 16 teams of 6 students each diagnosed 32 patients total. To prevent error, three replicates were done per patient and per positive and negative control. In addition to this, three replicates were done per calibration control, and three drop images were taken per unique PCR sample. In the final results, there were two teams that had inconclusive results. Aside from that, the majority of groups had successful conclusions. Some challenges encountered that may affected your data was light getting into the box or the light not shining through the drops the exact same each time.
What Bayes Statistics Imply about This Diagnostic Approach
Calculations
1. The probability that a patient will get a positive final test conclusion, given a positive PCR reaction was close to .9 (90%), making the test mostly reliable. The probability that a patient will get a positive PCR reaction given a positive final test was also close to .9 (90%).
2. The probability that a patient will get a negative final test conclusion, given a negative diagnostic signal was also close to .9 (90%), making the test mostly reliable. The probability that a patient will get a negative diagnostic signal, given a negative final test conclusion was over 1.0 (100%), making the test highly reliable.
3. The probability that a patient will develop the disease, given a positive final test conclusion was close to .7 (70%), making it less reliable than the previous tests. The probability that a patient will get a positive final test conclusion given that the patient has the disease was also close to .7 (70%).
4. The probability that a patient will not develop the disease, given a negative final test conclusion was close to .8 (80%), making the test mostly reliable. The probability that a patient will get a negative test conclusion, given that they do not have the disease was also close to .8 (80%).
Possible Sources of Error
Light exposure to the SYBR Green I and inside the box
Change in distance of the camera to the drop
Adding too much or too little with the micropipette
Intro to Computer-Aided Design
3D Modeling
Our team used Tinkercad to construct our product. The pre-made files for the components of the box were used to make our new product. Tinkercad was much easier to use than SolidWorks has been previously. We assembled the different parts together and changed the color of the pieces. In addition to the pre-made files, we added our logo (PCR-U) to the front of the box.
Our Design
Our design combines the PCR machine and the fluorimeter into one device. This makes it easier for the consumer to use. In the device, at the top is the PCR machinery and at the bottom is the dark box fluorimeter. Unlike the original OpenPCR design, in the box there is a camera that is connected to the front. This does not allow any light to enter the box, ensuring better results. Also, when plugging in the PCR machine to a computer, the data from the fluorimeter is also sent to the computer. This makes it easier to use the device because you don't have to use ImageJ to get the results.
Feature 1: Consumables
The consumables supplied with our machine are in a box that contains rows of pipette tips, tubes, slides, and labeled PCR mix and primers. When purchasing the device, the box of consumables, and a micropipette are included. Our re-designed PCR machine uses standard tubes, however they are still included in the purchase. If additional tips, tubes, slides, PCR mix, or primers are needed, they can also be purchased through our company. The price of buying them all together is cheaper than buying them separately.
Feature 2: Hardware - PCR Machine & Fluorimeter
Our product combines the Open PCR machine and the fluorimeter into one device. By combining the two machines, it is more simple to conduct PCR and get the results. At the top of the box is the Open PCR machinery, and the front of the box can open up to become a dark box for the fluorimeter. At the bottom of the box is a place for the slides to be inserted, and on the inside of the front of the box is a camera that takes pictures of the slides. A button is located on the right side of the box that when clicked takes pictures.
BME 100 Fall 2016
