Overview
Prioritizing both experimental feasibility and safety, our project utilizes Escherichia coli strains BL21(DE3) and DH5α as platforms for the development of bio-artistic tools. These strains exhibit severely attenuated viability in natural environments and are well-established as chassis organisms in synthetic biology due to their high safety profile. Furthermore, we have designed specialized hardware components to provide additional biological containment, thereby preventing bacterial escape. The safety of laboratory personnel and the public during outreach activities is also of paramount importance. This page provides a comprehensive introduction to the safety and reliability of our project.
Design Safety
Chassis Organism Safety
The BL21(DE3) and DH5α strains are both derived from E. coli K-12. After decades of laboratory adaptation, they possess highly attenuated characteristics:
Limited Environmental Survival: These strains lack essential genes required for colonization in the healthy human gut. Consequently, their viability outside enriched laboratory media (e.g., LB broth) is extremely limited.
Non-pathogenicity: They do not harbor known virulence factors, toxin genes, or invasion genes, and thus pose no infection risk to immunocompetent individuals.
Hardware-Enabled Physical Containment
To ensure robust containment, the engineered bacteria and their nutrients are encapsulated within a hydrogel matrix that is impermeable to bacterial cells. This primary containment is reinforced by an additional, outer hydrogel shell with a smaller pore size. This bilayer design enhances mechanical stability, reduces the risk of fracture, maintains permeability for small molecules, and more effectively restricts bacterial escape. Preliminary experiments confirm the efficacy of this design: while bacterial growth was detected in the surrounding medium from samples with a single hydrogel layer after 24 hours of shaking incubation, no bacterial escape was observed from samples with the double-layered shell. These results indicate that our physical containment strategy effectively supplements inherent biochemical safeguards.The staining module of the hardware also incorporates heating and ultraviolet (UV) irradiation sections. These features enable terminal decontamination of the hydrogel, fabric, and hardware components upon completion of the staining process via high-temperature and UV treatment.
Laboratory Safety
Safety is a fundamental prerequisite for all synthetic biology work. Our team is committed to implementing all necessary precautions to prevent harm to personnel.and the environment. We have established comprehensive laboratory safety guidelines, standardized experimental protocols, and conducted systematic training to ensure a safe working environment. Prior to commencing experimental work, all team members were required to demonstrate proficiency in these safety procedures.
Laboratory Safety Gallery
General Laboratory Safety Protocols
Personal Protective Equipment: Strict rules mandate the use of lab coats, gloves at all times within the laboratory, and utilize safety goggles if necessary.
Area Separation: Laboratory and rest areas are strictly segregated. Bringing food or drinks into the lab, or removing lab materials, is prohibited.
Chemical Safety: Chemicals are stored in a categorized and standardized manner. All procedures involving irritant or volatile chemicals are conducted within a fume hood.
Designated Hazard Zones: A specific area is designated for procedures involving potential hazards, such as electrophoresis, which uses mutagenic reagents.
Emergency Preparedness: The laboratory is equipped with comprehensive safety and emergency equipment, including fire blankets, extinguishers, smoke detectors, emergency showers, and eye-wash stations.
General Laboratory Safety Protocols
Project-Specific Biosafety
Although BL21(DE3) and DH5α are classified as Safety Level 1 microorganisms, a potential risk of plasmid transfer exists. Therefore, all bacterial waste and used culture media are sterilized prior to disposal. All handling of live cultures, including the opening of culture tubes, would be performed exclusively within a biosafety cabinet to prevent aerosol release.Our team benefits from the supervision and expertise of our instructor, Shen Hongyu, who provided detailed guidance on experimental procedures and safety protocols. This oversight ensures a safe experimental environment and facilitates efficient project execution.
Safety in Future Applications
Following stage-wise experimental verification, the engineered genetic circuits will be transferred into an auxotrophic chassis strain. This additional safeguard will ensure that, in the final application, the bacterial cells cannot persist outside the controlled conditions of the artistic installation.
Safety Training and Implementation
General Laboratory Training
Before initiating experiments, all team members completed laboratory safety training. This training covered fundamental experimental techniques, safety protocols, and the operation of standard laboratory equipment. During initial experiments, team members worked in pairs to ensure mutual supervision and adherence to safety standards. Our instructor conducts regular laboratory inspections to ensure compliance and correct operational techniques. Prominent safety signage is displayed on all major instruments.
safety-lab
Safety training in laboratory
Safety signage on the autoclave
Biosafety Cabinet Training
Specific training on the correct use of biosafety cabinets was conducted, emphasizing the critical distinction between biosafety cabinets (which protect both the user and the sample) and laminar flow hoods (which protect only the sample). To maintain airflow and performance, overloading the biosafety cabinet workspace is avoided. Surfaces are decontaminated according to established procedures before and after each use.
Instrument-Specific Training
Training included the safe operation of centrifuges and autoclaves. Protocols emphasized operational details and specific precautions. For example, the use of high-speed centrifuges requires strict adherence to rotor balancing and lid-securing procedures. Autoclave use involves verifying water levels before operation and confirming that temperature and pressure have fully normalized before removing sterilized materials. Additional training was provided for the safe use of blue-light transilluminators and UV imagers to prevent potential harm from light exposure
Safety in Human Practices
Personnel Safety during Public Engagement
During public engagement activities, such as laboratory tours, all visitors receive a comprehensive safety briefing. The importance of Personal Protective Equipment (PPE) is emphasized, and participants are strictly required to wear gloves and masks.
Safety signage on the autoclave.
Protection of Participant Privacy
In all human practices activities, the protection of participant privacy and rights is ensured. Specifically, survey data is collected anonymously, with a commitment that the data will not be used for any purpose other than the stated research. For interviews requiring audio or video recording, informed consent is obtained beforehand. Prior consent is also secured if interview content is intended for public dissemination. In essence, every reasonable effort is made to safeguard the personal privacy of all participants involved in this project.
The Informed Consent for Human Practices Research: BNUZH-China Informed Consent for Human Practices Research