A portable algae culturing equipment that can provide the necessary resource of the algae growth, including the light, suitable temperature, and CO2.
Lighting system: the color of the light was set to be white for better efficiency in boosting the algae growth.
The lighting system uses two RGB-adjustable LED boards, and uses one separate arduino board to drive it.
Temperature monitor: the temperature information was gathered from each culturing containers and shown on a LED screen for reference.
Temperature probes use DS18B20 as sensor. This kind of sensor can detect temperature with high precision, and it can run under water. The sensors use a serial bus to communicate with the arduino motherboard.
Temperature adjusting: a heater was set in each container for adjusting. In order to maintain the best effect of growth temperature, the temperature adjusting system program was coded to ensure at least 5 of 8 containers were higher than 24oC, and lower than 25.5oC. If the heating system is running, the screen will show a “H” sign at the end of the temperature.
Air exchanging system: the CO2 supplement was ensured by the air pump connecting each container.
Homemade Gene Gun
The dynamic part of the gene gun provides the compressed gas to accelerate the DNA-coated particles to target cells.
We searched the Internet and found one article about the DIY gene gun. The author decided to use a bicycle CO2 tire inflator to obtain high-pressure gas. However, we didn’t adopt his method. The reasons are as follows. First, the gas pressure in the Co2 inflator can’t satisfy our needs. The average commercial CO2 inflator provides up to 130 psi gas pressure, which can’t even meet the minimum pressure requirement of the gene gun. Moreover, the limited size of the inflator makes frequent experiments inefficient. Our team contacted the Maker Workshop on campus, and the instructor permitted us to use the high-pressure air pump that meets our needs. The air pump solved both problems since it is reusable and powerful enough to make high pressure gas. The air pump integrated a pressure gauge, which saved us from spending more money on a new gauge.
We adopted the original structure of the gun muzzle. We designed a detachable pressing block at the muzzle, which can not only effectively fix the macrocarrier and bullet (and keep them at a certain distance), but also facilitate the disassembly and replacement of the macrocarrier or bullet. We have designed a cone for the muzzle of the gun, which is convenient for the bullet to scatter evenly, thus optimizing the firing result. It is worth mentioning that because of the air pump and block pressing structure, we can accurately provide the required pressure and make the gun enter the launching state with efficiency and safety. Therefore, we removed the rupture disk in the original design, which again saved us a great expense.
The whole operation process is quite simple. First of all, the screen and macrocarrier are installed on the muzzle, and the cells to be transformed are placed under the gun. Secondly, the air pump is opened at the far end, adjusting to the required air pressure. At the same time, the “air pump to the solenoid valve” section is filled of gas. Finally, through the relay, the switch of the solenoid valve is turned on, and the transmission is completed within 0.01s