The Hydro Guardian biosensor is designed for real-world application in monitoring water quality in diverse settings, including low-resource environments, and is aligned with the global SDGs.
In consideration of the prospective application scenario, it is necessary to implement the outlined safety measures in future applications.

Real-World Implementation of our Hydro Guardian Biosensor

Our Hydro Guardian biosensor is an innovative tool designed to detect antibiotics and heavy metal residues in water using genetically engineered HEK (Human Embryonic Kidney) cells. Employing a fluorescence-based detection system, it provides real-time monitoring of pollutants, making it highly adaptable for sectors such as environmental protection, industrial wastewater treatment, and healthcare. Its affordability and user-friendly design make it particularly suited for resource-limited areas like the Global South, supporting widespread access to essential monitoring technologies.

Future Application Scenario: Environmental Protection, Pollution Control, Industrial Wastewater Monitoring and Healthcare

As environmental regulations evolve, the Hydro Guardian biosensor will excel in detecting trace amounts of pollutants such as heavy metals and antibiotics in liquid samples. Its sensitivity will enable continuous monitoring to ensure early detection and timely interventions to prevent environmental contamination.

Specific Scenarios:

Monitoring Near Industrial Sites and Mining Operations:
In regions near industrial or mining operations, where pollutants can easily seep into river systems or groundwater, the Hydro Guardian could be able to detect harmful heavy metal substances in real time. By providing immediate alerts, it would help authorities mitigate health and environmental risks before they become critical.
Industrial Wastewater Monitoring:
Industries such as metal plating will be able to continuously monitor wastewater for heavy metals like chromium and nickel. The Hydro Guardian would assist in maintaining regulatory compliance by ensuring pollutant levels remain within safe limits before discharge, preventing pollution and avoiding regulatory fines.
Urban Drainage and Wastewater Treatment Systems:
In urban settings, such as the wastewater systems managed by Stadtentwässerung Hannover, the Hydro Guardian biosensor could enhance current monitoring efforts. During an interview with Peer Lindenhayn, the representative for press and public relations at Stadtentwässerung Hannover, we learned about the existing methods used for monitoring contaminants in wastewater treatment plants. While heavy metals are routinely monitored, antibiotics are not regularly tested due to the lack of legal requirements.

Interview Insights: Peer Lindenhayn highlighted challenges in detecting and removing pollutants, noting that matrix effects in wastewater can complicate accuracy. The elimination rates of antibiotics in current treatment processes remain unknown, as they are not routinely monitored. The Hydro Guardian biosensor offers a promising avenue for additional antibiotic monitoring, depending on its sensitivity and specificity. For the full interview, see Human Practices.

Expert Opinion from Academia: In an interview with Professor Marcus Horn from the Institute for Microbiology at Leibniz University Hannover, the value of biosensors like Hydro Guardian was emphasized. Professor Horn noted that biosensors can help detect lead in drinking water, especially in households with outdated lead pipes. They can also be used in wastewater treatment plants to monitor the removal of antibiotics and in rivers and lakes to assess contamination levels and their potential ecological impact. For the full interview, see Human Practices.
Field Monitoring by Environmental Agencies:
Government bodies, NGOs, and environmental organizations could deploy portable versions of the Hydro Guardian biosensor to monitor water quality in rivers, lakes, and streams near industrial sites. Real-time detection capabilities enable swift action to prevent long-term environmental damage by acting promptly when pollutants are detected.
Continuous Monitoring in Industrial Zones:
Industries such as mining, metal processing, and chemical manufacturing often discharge heavy metals and other harmful substances into wastewater systems. The Hydro Guardian biosensor could detect and quantify trace amounts of heavy metals and antibiotics. This will empower operators to intervene when pollutants exceed safe thresholds.
Collaboration with Water Purification Companies:
We spoke to What a Bird, a company specializing in water purification solutions, particularly water filter pumps designed for jerrycans (Human Practices). Their products aim to provide safe drinking water in areas lacking access to clean water sources, aligning with the Hydro Guardian's mission to improve water quality in resource-limited settings. Through our discussions, we explored integrating the biosensor with their water filtration systems to enhance the detection and removal of contaminants. What a Bird emphasized the importance of creating affordable and easy-to-use devices to ensure widespread adoption, especially in the Global South. Companies such as What a Bird, specializing in water purification, will likely integrate the Hydro Guardian into their filtration systems, enhancing detection capabilities. These collaborations would facilitate affordable, easy-to-use devices that align with the needs of communities in the Global South.
Healthcare, Toxicology, Pharmaceutical, and Biotechnology:
Beyond environmental applications, the Hydro Guardian biosensor holds significant promise in healthcare, pharmaceutical manufacturing, and toxicology, where accurate detection of contaminants is crucial for public health and product safety. Its ability to detect extremely low concentrations of heavy metals and antibiotics in biological samples offers new possibilities for rapid diagnosis, intervention and preventative measures.

Safety Protocols for Genetically Modified HEK Cell Biosensors

Ensuring the safety of users and the environment is a critical priority for us in the Hydro Guardian project, especially when utilizing genetically modified HEK cells. Based on the application scenario, some or all of the following safety measures would need to be implemented in future applications:

Biosafety and Genetic Containment:

The genetically modified HEK cells will be fully enclosed within a controlled system to prevent any accidental release into the environment. These cells are engineered to survive only under specific conditions—such as a specialized culture medium and a constant temperature of 37°C. Outside these parameters, the cells cannot survive ensuring safety in the event of accidental exposure. Later, cell-free expression systems might be employed. However, this would need potentially some “membrane”-anchor for the kinase.

Physical Containment in Sealed Test Kits:

The HEK cells will be housed in sealed cartridges or advanced microfluidic systems that prevent any interaction with the external environment. After testing, the entire cartridge will be securely disposed of, preventing any release of genetically modified organisms (GMOs). This approach ensures safe usage in both field applications and home-based testing kits.

Non-Replicative and Genetically Safe Cells:

The HEK cells will be engineered to be non-replicative, meaning they cannot divide outside their controlled environment. Additionally, genetic "kill-switches" will be incorporated, causing the cells to self-destruct when exposed to specific external triggers, such as changes in oxygen levels or temperature. This ensures the cells cannot survive outside their intended testing environment, reinforcing biosafety.

Environmental and User Safety Protocols:

The closed system of the Hydro Guardian biosensor ensures that no genetically modified HEK cells, antibiotics, or heavy metals escape into the environment. Multiple layers of containment protect users from direct contact with the genetically modified cells during testing and allows a safe usage.

Automated Sterilization and Disposal Methods:

Future biosensor models could include integrated sterilization systems—such as chemical inactivation or UV sterilization—that activate immediately after testing. These systems destroy all live cells, ensuring the device is safe for disposal. For industrial applications, automated sterilization methods like autoclaving will handle waste from large-scale biosensing operations.

Compliance with Biosafety Regulations:

The Hydro Guardian biosensor need to comply with international biosafety regulations set by organizations like the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). The genetically modified HEK cells will meet or exceed Biosafety Level 1 (BSL-1) standards, with all protocols for GMO handling, transport, and disposal rigorously followed.

GMO Waste Disposal Protocols:

Waste containing genetically modified HEK cells needs to be treated as biohazardous GMO waste. Secure biohazard containers will collect the waste, which will be disposed of through approved methods like incineration or autoclaving. Portable biosensors may feature built-in sterilization functions to neutralize cells before disposal.

Environmentally Sustainable Design:

Future designs of the biosensor will incorporate eco-friendly materials and biodegradable components. The HEK cells will be engineered to die quickly if exposed to natural environments, further reducing any risk of environmental impact.
By providing an affordable, real-time water quality monitoring solution, the Hydro Guardian biosensor contributes to improving access to clean water, reducing health risks, and promoting sustainable industrial practices. It supports responsible consumption by enabling industries to monitor and manage their pollutant output effectively. For more details on how Hydro Guardian aligns with the SDGs, please visit our Sustainable page.

What We Have Learned from Combining Pro- and Eukaryotic Elements

During our project, we gained fascinating insights into how synthetic biology has made it possible to introduce functional prokaryotic proteins into eukaryotic cell lines. This integration has not only opened up new perspectives but has also shown that it is indeed possible to transfer complex prokaryotic signaling cascades into eukaryotic cells.
Our experiments have shown that key proteins and signaling molecules from prokaryotic organisms, such as S. aureus in our case, can be integrated into the cellular mechanisms of eukaryotes. This interaction allowed us to exploit the strengths of both systems to create an innovative biosensor.

Conclusion

The Hydro Guardian biosensor represents a significant advancement in monitoring environmental pollutants and safeguarding public health. By integrating cutting-edge technologies with stringent safety protocols, the Hydro Guardian biosensor ensures effective detection of antibiotics and heavy metals while safeguarding users and the environment from potential risks associated with genetically modified organisms. The insights gained from our interviews with industry professionals, environmental experts, and companies like Stadtentwässerung Hannover, Professor Marcus Horn, and What a Bird have been invaluable. Their expertise has shaped the biosensor's design and implementation strategies, ensuring it meets the needs of various stakeholders across environmental and healthcare sectors.
Its real-time detection capabilities, coupled with rigorous safety protocols and collaborative input from experts and industry partners, position it as a vital tool in addressing global challenges related to water quality and contamination. Its detection capabilities, rigorous safety standards, and expert collaboration not only address critical water quality and contamination issues, but also enable the project to actively contribute to the achievement of key Sustainable Development Goals (SDGs), described in more detail on the Sustainable page.