The pool testing backlight offers an efficient way to perform pool/group testing on a 96 well plate, without robotic pipetting machine or paper templates.
The Pool Testing Backlight (pictured below) is a enclosed device with a seat for a standard 96-well plate. The backlight contains an 8x12 LED array underneath a polycarbonate window. When a well plate is placed into its seat, individual LED's on the array can be turned on to indicate certain desired wells on the well plate.
The LED array is built around an Arduino Nano, and uses three 8-bit shift register IC's as a serial-to-parallel converter to achieve mulitplexing on the LED array. The driver software communicates with the Arduino Nano through a USB-Serial connection, which also supplies the necessary 5V to the Arduino Nano.
The software for the pool testing backlight is a driver program that serves a couple of purposes:
- Load and interpret multiple data formats
- Send LED-lighting information to the backlight device
- Interact with users through a Graphical interface
The software was written in Python 3.6 and the GUI was built using the TKinter module. The module cx_freeze was used to create executable files from the original Python script.
The driver software for the pool-testing-backlight can be downloaded here. The program itself is located at "Pool Testing Backlight"/Executables/backlight.exe. The exe file should not be removed from the Executables directory. I recommend adding backlight.exe to your PATH or system variables, but that is purely optional. An alternative is to simply create a shortcut for backlight.exe somewhere accessible, such as on your desktop.
The pool testing backlight offers two methods to load a specific testing scheme: through text file or by selecting a sample size.
- Through Text File: Loading your testing scheme through a text file is as simple as saving your testing matrix to a text file. A sample input is available here. Pre made lists containing the matrix data can be found at Origami Assays.
- Through sample dimension: The pool-testing-backlight software allows you to select the length/width of an array containing patient samples. For example, to pool 400 patients' samples, I would select "20" when prompted by the software, and the program will generate a scheme to pool the 400 patients' samples into wells 1-60 on the well plate.
- Run backlight.exe
- Ensure the backlight is connected to your computer via USB. If the program does not detect a backlight, try different USB ports and check Device Manager to identfiy if a serial device is found.
- Follow the prompts given by the software
Follow any troubleshooting steps listed in the instructions. If that doesn't fix the issue, open an issue through GitHub.