Abstract: In the lab, we have to respect numerous safety regulations for the security and health of others and the environment.
We received a one-week long training about lab safety at Wuhan University, and we learnt about basic safety rules and common microbiology’s techniques in lab. After the training, we could use the common equipment in lab such as centrifuge properly and proficiently. Moreover, we realized that safety was the most important and we should follow the rules strictly and ask our instructors for help when encounter problems to avoid lab technicians from being hurt in the lab.
Basic rules in a lab
We have to apply the basic safety principles in all laboratory rooms:
1. No personal belongings or food is allowed in the lab.
2. Always keep work stations clean and in good order.
3. Never open the windows without permission. Always keep the doors closed.
1. Never touch anything in a non-contamination area with gloves on.
2. Always be properly trained for all the procedures. Unauthorized experiments or procedures must not be attempted. Operation of special instruments should be done with the help of a qualified instructor.
3. Safety rules are to be strictly followed.
4. Taps should be closed after use to prevent an overflow of water. If an instrument or piece of equipment malfunctions during use, the situation is to be reported to a technician immediately. Gels like culture medium or agarose gel are to be kept away from the sink. Solids are to be cleaned out afterwards, especially from an Eppendorf tube.
5. In case of a fire, all power should be cut off and all flammable materials should be removed. The situation is to be reported immediately.
6. Never operate electrical equipment with wet hands.
7. Flammable materials are to be kept away from open fires.
8. Never taste or intentionally sniff chemicals. Perform manipulations of materials that pose an inhalation hazard in a chemical fume hood to control exposure. Never leave reactions unattended.
9. When handling corrosive materials, gloves and other chemically resistant protective clothing should be worn to protect against skin contact. In case of an accident, immediately clean the exposed areas of skin and seek medical advice.
10. Any experiments involving radioactive materials is to be carried out in special labs and supervised by qualified instructors.
11. In case of a biological spill, wipe up spill and clean the surface with a suitable disinfectant and immediately wash exposed areas of skin with soap and water.
12. Wear protective eyewear and face shield while operating instruments that produce ultraviolet radiation. Safety glasses should be used when operating UV transilluminators or gel imaging systems.
13. It is forbidden to smoke in all rooms.
14. It is forbidden to drink and eat in the laboratory rooms.
15. It is compulsory to wear a closed lab coat in cotton.
16. It is compulsory to wear closed shoes.
17. Long hair must be tied back.
There are also others precautions when working with biological organisms:
- We need to wash our hands regularly.
- It is compulsory to wear gloves except for the use of an electric burner.
- In some cases (UV light, projection risk), it is compulsory to wear protection glasses.
Safety in the Lab
- Equipments: As long as we manipulate in the lab, we have to wear the following personal protective equipment (a conventional lab coat, closed with long sleeves, closed shoes, gloves, and glasses if needed).
- Waste: Different trash containers are available in the lab:
- One for biological waste. This waste will be autoclaved before being thrown out.
- One for common waste.
- Special waste for chemicals.
- Special waste for waste in contact with arsenic salts.
- Biological safety cabinet: To work into a sterile area and thus avoid external contamination by unwanted microorganisms, we have used a biological safety cabinet (FASTER – Ultrasafe). This BSC was cleaned with ethanol before and after each manipulation. A control of maintenance is done each year.
- Water-bathes: We often used the water-bathes for transformation and other supplementary processes. They can be dangerous because of the exposure to hot or even boiling water. To protect us, wearing a lab coat and special gloves was indispensable. The same equipment is necessary for the microwave.
- arsenic salts: arsenic salts are the testing reagents of our gene pass ways, and it is highly detrimental to human body. Thus, in order to protect us, gloves, goggles, and ventilation hood must be used during the experiment.
- Chemical hood: We used the chemical hood when we had to manipulate dangerous and volatile chemicals (for example: the adding of TEMED and arsenic salts)
Safety for our project
We have described above the relevant security measures taken all through summer to minimize the risk of incidents in the lab. However, when working in the field of synthetic biology, one of the main concerns is the dissemination of our engineered strain, which could be a threat to the public and the environment.
In the experiment we used E. coli DH5 α as well as E. coli BL-21. E. coli DH5 α is a mutagenized strain that mainly exhibits immunological deficiency of foreign DNA. It is a strain used for genetic engineering and lacks a certain degree of immune mechanism compared to normal strains. BL-21 is a chemically competent E. coli cell suitable for transformation and high-level protein expression using a T7 RNA polymerase-IPTG induction system. In E. coli BL-21, the activity of proteases is relatively low, so that the target protein is not easily degraded. In addition, BL21 contains T7 RNA polymerase induced by IPTG and therefore is suitable for protein expression induced by the T7 promoter. Though these 2 bacteria may not be pathogenic, sterilization is needed after the experiment.