Project Overview: Remedix – A Responsible Solution to Pharmaceutical Residues

Event Title: Doctor Survey on the Use and Disposal of Tetracyclines and Aspirin (salicylate)

Summary of Event:

We conducted a survey with 21 clinicians in Hong Kong to understand medical practices, disposal behaviours, and awareness regarding tetracyclines and Aspirin (salicylate). Doctors were chosen as key stakeholders because they are frontline prescribers whose decisions directly affect both patient health and environmental impact. The consultation aimed to gather insights on prescription frequency, disposal routines, and perceptions of pollution risks.

Key Insights:

• High Prescription Rates: Tetracyclines are frequently prescribed for respiratory, skin, urinary, and gynecological infections, while Aspirin (salicylate) remain essential for cardiovascular care and pain management.
• Improper Disposal: Despite 53% of respondents returning unused medicines to pharmacies, others admitted to discarding them in general waste or storing them, with most clinics lacking formal disposal protocols.
• Low Awareness: A large proportion of clinicians were unaware or uncertain about the environmental consequences of pharmaceutical residues.
• Support for Innovation: More than half supported the development of bioremediation technologies to address the issue.

Conclusion:

The survey highlights both the widespread use of these pharmaceuticals and the shortcomings in disposal and awareness. This underscores the relevance of our project in developing detection and degradation solutions, while ensuring our approach aligns with the medical community's practices and readiness to adopt innovative strategies.

Event Title: Interview with Hong Kong Social Enterprise Veterinary Hospital

Summary of Event:

We consulted veterinarians at the Hong Kong Social Enterprise Veterinary Hospital because of their central role in prescribing antibiotics for animals and managing related pharmaceutical waste. The aim was to understand common prescription practices, disposal protocols, and measures taken to prevent environmental contamination.

Key Insights:

• Antibiotics, particularly tetracycline and amoxicillin, are used in about 30% of daily cases.
• Veterinarians emphasize the need for owners to ensure pets complete the full treatment course to reduce the risk of antibiotic resistance.
• As full compliance is expected, no disposal instructions are provided to owners for leftover antibiotics.
• Expired pharmaceuticals are strictly managed by medical waste teams, with disposal in rubbish bins or sewage systems prohibited.

Conclusion:

The discussion revealed strong veterinary practices in both antibiotic prescription and waste management. However, the lack of disposal guidance for owners could leave a potential gap if incomplete courses or leftover drugs arise, underscoring the importance of integrating awareness and environmental safeguards into broader pharmaceutical management.

Event Title: Interview with Pet Shops and Aquariums at Tung Choi Street

Summary of Event:

We interviewed several aquarium and pet shop owners along Tung Choi Street to explore their role in the use and disposal of antibiotics. Pet shops and aquariums were consulted because they sell products for pet care and treatment, and thus could influence how antibiotics are managed in this sector. The interviews aimed to uncover whether antibiotics are sold, and how shopkeepers guide customers on responsible disposal practices.

Key Insights:

• Customer guidance is lacking shopkeepers generally assume pets will complete the prescribed treatment, meaning customers are not offered advice on how to handle leftover or expired medications.
• This reflects a low awareness of disposal issues, leaving potential gaps if pet owners do end up with excess or unused antibiotics.

Conclusion:

The interviews revealed that while strict regulations prevent the sale of antibiotics in pet shops and aquariums, awareness of safe disposal practices remains low. This gap highlights the importance of public education and guidance in reducing the risk of improper disposal, and it reinforces the relevance of our project Remedix as a complementary tool for managing pharmaceutical residues in everyday contexts.

Event Title: Consultation with Government Officer

Summary of Event:

We consulted officers from Agriculture, Fisheries and Conservation Department (AFCD) and Drainage Services Department (DSD) to understand government policies and technologies related to wastewater management, medical waste disposal, and the monitoring of pharmaceutical residues, particularly antibiotics. The purpose of this consultation was to clarify how Hong Kong regulates and treats wastewater that may contain antibiotic pollutants, and to identify both the government's monitoring capacity and the existing challenges in enforcement.

Key Insights:

• Regulation Framework: Wastewater discharge is strictly regulated under the Water Pollution Control Ordinance, with licenses issued by the Environmental Protection Department (EPD). Antibiotics are categorized as chemical waste and subject to the Waste Disposal Ordinance.
• Waste Management: Medical and chemical waste must follow a full chain of segregation, packaging, collection, transport, and treatment at licensed facilities such as the Chemical Waste Treatment Center. Improper disposal in rubbish bins or sewage systems is prohibited.
• Antibiotic Monitoring: A baseline study (2020-2021) found residual levels of 26 antibiotics in Hong Kong's water bodies below harmful concentrations, posing no significant ecological risk at present.
• Wastewater Treatment Efficiency: Existing plants can remove most antibiotic residues effectively, with secondary treatment achieving over 90% removal, consistent with international benchmarks.
• Challenges: High treatment costs, risks of secondary pollution if mishandled, and difficulty enforcing compliance across all stakeholders, especially households.
• Enforcement: While antibiotics are heavily regulated, ensuring proper disposal from households remains difficult despite sealed landfills designed to prevent leakage.

Conclusion:

The consultation confirmed that Hong Kong has a comprehensive regulatory and treatment framework for antibiotic waste and wastewater management. However, enforcement and household-level compliance remain weak points. These insights highlight the importance of our project in providing additional technological solutions—such as detection and bioremediation—that can complement existing infrastructure and address gaps in antibiotic pollution control.

Event Title: Street Interview on Public Awareness of Environmental Issues

Summary of Event:

We conducted street interviews with members of the public to investigate their awareness and opinions on three key topics: the use of genetically modified (GM) bacteria in water testing, how people dispose of expired or leftover medications, and their perceptions of local river pollution. We consulted the public because their behaviors and attitudes directly influence environmental risks and the effectiveness of new technologies.

Key Insights:

• GM Bacteria for Water Testing: Only 20% of respondents believed it harmful, while the majority had neutral or unclear opinions. This shows low understanding and no strong opposition, but also a lack of informed support.
• Medication Disposal: A striking 83.3% of respondents throw expired or leftover drugs in the trash, with no mention of safe disposal methods such as returning to pharmacies. This reflects a clear knowledge gap about environmental risks.
• River Pollution Awareness: Only a small portion (around 33.4%) noticed or believed local river pollution, while two-thirds said nothing about rivers at all. Public concern for water quality remains very low.

Conclusion:

The street interviews revealed weak public awareness in all three areas: biotechnology applications, proper medication disposal, and local river pollution. These findings highlight the urgent need for targeted education campaigns to improve understanding and encourage environmentally responsible practices, ensuring that technological solutions are supported by informed community behavior.

Event Title: Interview with Pig Farm Owner Mr. Lo Yam-keung

Summary of Event:

We interviewed Mr. Lo Yam-keung, a pig farm owner, to understand the practical realities of antibiotic use in pig farming. Farmers were consulted because their practices directly shape food safety, animal health, and environmental impact. Mr. Lo discussed antibiotic usage patterns, his perspective on testing technologies, and the regulatory framework in Hong Kong.

Key Insights:

• Antibiotic Use: Farms generally depend on older, cheaper antibiotics since newer ones are expensive and discouraged for agricultural use. While aware of resistance risks, Mr. Lo explained that antibiotics are difficult to avoid because they help prevent disease and promote growth. Usage has gradually increased over time.
• Testing Machines: He does not rely on testing equipment, believing that he can control dosage manually. He views machine testing as costly, time-consuming, and offering limited benefits, with little demand across the industry.
• Regulatory Oversight: The Agriculture, Fisheries and Conservation Department conducts annual random checks on feed and waste samples. Residues result in warnings, while banned antibiotics can lead to immediate farm closure. Mr. Lo believes this system has kept misuse relatively rare in Hong Kong.

Conclusion:

The interview showed that while antibiotics remain essential in pig farming, existing regulations limit serious misuse. However, consumer concerns persist due to occasional reports of residues in pork. This creates an opportunity for our project Remedix to provide a cost-effective and rapid screening solution, strengthening food safety assurance and helping build greater trust between farmers, regulators, and the public. As we continue our product development, we should focus on highlighting our method's affordability, speed and accessibility despite semi-quantitative limitations.

Event Title: Interview with Fish Farm Owner Mr. Chu Tak-nang

Summary of Event:

We interviewed Mr. Chu Tak-nang, a local fish farmer in Nam Sang Wai and a participant of the Accredited Fish Farm Scheme. He was consulted to understand the practical use of antibiotics in aquaculture and the broader implications for food safety and environmental protection. Mr. Chu shared his experiences with fish, pig, poultry, and shrimp farming practices, providing comparative insights into antibiotic use across different livestock systems.

Key Insights:

• Fish Farming: Antibiotics are rarely used; lime is the main disinfectant for ponds. In the Accredited Fish Farm Scheme (covering about 50-60% of farms), water quality and residues are tested regularly. Farms outside the scheme lack such regulation. Antibiotics are costly, so their use is naturally limited.
• Pig Farming: Antibiotics are more widely used because pigs are vulnerable without them. Veterinarians prescribe medicines when needed, helping prevent indiscriminate usage.
• Ducks and Geese: Given brown sugar and antibiotics when young, helping them stay healthy later.
• Shrimp Farming: Antibiotics are used more frequently due to higher susceptibility to disease outbreaks.

Conclusion:

The interview highlighted that antibiotic use in aquaculture varies by species and farming density, with fish generally requiring fewer antibiotics than shrimp. Mr. Chu emphasized that beyond controlling antibiotic use, consumer confidence is the central issue. Reliable and affordable residue testing could help farmers demonstrate product safety, strengthen public trust, and support the sustainability of Hong Kong's aquaculture industry. This aligns directly with the purpose of our project Remedix, which aims to provide such transparent and trustworthy solutions.

Event Title: Interview with Professor Wong Ming-hung

Summary of Event:

We consulted Professor Wong Ming-hung from The Education University of Hong Kong, a renowned environmental science advisor and Editor-in-Chief of Environmental Geochemistry and Health. With extensive expertise in pollution, public health, and sustainability education, he was invited to provide feedback on our project Remedix. The discussion focused on antibiotic use and impacts, waste treatment practices, the strengths and weaknesses of our prototype, and how our project could be positioned for broader social and environmental relevance.

Key Insights:

• Antibiotic Usage: Widely applied in livestock and aquaculture to promote growth and prevent infections. This contributes to antibiotic resistance, superbugs, and genetic mutations. Tetracycline remains a commonly used drug.
• Current Treatment: High-temperature incineration is standard, Household wastewater often retains pharmaceutical residues after DSD plant treatment, meaning residues can reach the sea.
• Project Design: Using E. coli for early detection is appropriate, but cost may be an issue when treating large water bodies. We should offer a controllable, simple solution with clear color-change indicators, making observations easier and more effective than bulky systems.
• Social and Marketing Impact: Stress the dangers of genetic mutations from antibiotic resistance in hospitals and farms. Citizens are generally aware of antibiotic resistance, so messaging should highlight how Remedix addresses this problem for both human and animal health.
• Global and Local Context: Hong Kong has relatively strong measures such as the Accredited Fish Farm Scheme, but global practices in places like Southeast Asia or Africa still pose serious risks. Antibiotic pollution must be recognized as a wider global issue.

Conclusion:

Professor Wong's insights guided us to improve both the technical clarity and the societal framing of Remedix. His guidance on ethical aspects, emphasis on highlighting resistance risks, and presenting clear, data-backed demonstrations strengthened the scientific credibility of our project. At the same time, his advice on communication and global context reminded us that Remedix should not only serve as a scientific solution but also as a tool to raise public awareness and promote sustainable practices worldwide.

Event Title: Interview with Professor Yuan Zhiguo

Summary of Event:

We interviewed Professor Yuan Zhiguo, Chair Professor of Urban Water Management at City University of Hong Kong, to gain expert insights into antibiotic residues in water management systems. Given his expertise in sustainable urban water management and environmental biotechnology, we consulted him to better understand current wastewater treatment limitations, potential improvements, and the role of our project Remedix in addressing these challenges.

Key Insights:

• Comparison of pharmaceutical residues detection methods: Existing methods: Highly accurate but costly, time-consuming, complex, and not widely accessible. Suggesting that the use of synthetic biology can potentially offer a portable, quick, low-cost, and accessible detection method to the public, though semi-quantitative and less precise.
• Regulation and Tracking: The Hong Kong government has implemented regulations on the use and disposal of antibiotics and medications, but the public still does not treat the issue seriously enough. Our product could help by creating a "map" that tracks abnormalities and identifies violators.
• Current Treatment Practices: Chemical removal methods achieve only ~20% removal. Simpler methods, such as those used in Stonecutters plant or incineration, remain limited. Overflow from treatment plants during storms can release untreated antibiotics into the ocean. Persistent residues in soil may also leach back into water or accumulate in plants.
• Future Practices: Reduce unnecessary antibiotic prescriptions and strengthen public education on safe disposal. Place biosensors at key monitoring points (e.g., sewage pipes) to better trace contamination sources and support stronger legislation.

Conclusion:

Professor Yuan emphasized that while advanced degradation technologies exist, their limited cost-effectiveness and high energy demands restrict their use in Hong Kong. His feedback highlighted the urgency of developing accessible solutions like Remedix that can monitor and help reduce antibiotic residues. His advice also reinforced the importance of connecting our project to broader policy and public education efforts, ensuring its impact extends beyond lab innovation to real-world environmental protection. For the sake of publicity and promotion, we should differentiate our product from existing methods.

Event Title: Interview with Dr. Cheung Ka Tik - Hong Kong Metropolitan University

Summary of Event:

The team conducted an interview with Dr. Cheung Ka Tik, an expert in infectious diseases, antibiotic susceptibility, and zoonotic research at Hong Kong Metropolitan University. The discussion explored the public health implications, policy gaps, and technological potential of antibiotic detection in Hong Kong's environment. Dr. Cheung emphasized the urgent need for stronger regulation of veterinary antibiotic use, improved public education on antibiotic disposal, and the adaptability of biosensing technology for broader applications, including clinical testing for human bacterial infections.

Key Insights:

• Antibiotic Misuse and Policy Gaps: There is no regulation on veterinary antibiotic use in Hong Kong, leading to excessive use in animals and contributing to environmental resistance.
• Public Education: Misuse and improper disposal of antibiotics stem from limited awareness. Educational campaigns are needed to promote correct usage and disposal habits.
• Potential Application: The detection system could be adapted for clinical testing, providing a fast, on-site method to identify bacterial infections in human samples and support timely medical decisions.

Conclusion:

Dr. Cheung's insights highlighted that combating antibiotic misuse and pollution requires an integrated approach combining regulatory reform, public engagement, and technological innovation. He encouraged the team to continue developing the Remedix system as a versatile platform—capable of supporting both environmental monitoring and clinical diagnostics—to enhance antibiotic management and protect public health in Hong Kong.

Event Title: Interview with Prof. Tam Fung-yee, Nora

Summary of Event:

We interviewed Prof. Nora Tam Fung-yee, Chair Professor of Environmental Science and Conservation at HKMU, to gain expert feedback on the design and validation of our biosensor project Remedix. Prof. Tam focused on several key areas: E. coli culturing methods, optimization of alginate bead encapsulation, and the design of effective reporter systems for detecting tetracycline and salicylate. She also provided recommendations on how outputs should be presented to end users to ensure clarity and reliability. Her suggestions have given us valuable direction for refining our prototype and strengthening the scientific foundations of the project.

Key Insights:

• E. coli Culturing: TThe growth phase should be verified using a camera-assisted method, complemented by optical density (OD) measurements.
• Reporter and GM E. coli Design: Prof. Tam specifically suggested improving the design of genetically modified E. coli to detect tetracycline and salicylate through carefully chosen reporter systems. She emphasized that the reporters should meet several criteria: Rapid response with minimal delay between chemical detection and visible signal. Distinct color output that can be observed easily, even in sewage or turbid water. High sensitivity to detect pollutant concentrations at or below health-relevant thresholds. Signal stability, ensuring the reporter's color does not fade too quickly or overlap with other reactions.
• Testing of the beads: Prof. Tam agreed that alginate beads represent a valid and effective solution for containing genetically modified E. coli. However, a functional test of the beads is essential to confirm our claim.
• Output to Users: The system should present clear concentration data for tetracycline or salicylate. A single-color readout supported with a linear regression plot is suitable.

Conclusion:

Prof. Tam's input has guided us to improve Remedix in practical and decisive ways. She advised verifying E. coli growth phases with both imaging and OD measurements, refining GM E. coli reporter design to ensure speed, visibility, sensitivity, and stability, and testing alginate beads to confirm their effectiveness as a containment and sensing platform. She also emphasized the importance of clear concentration readouts and warnings for users. With her guidance, Remedix is better positioned to become a scientifically sound, field-ready tool for detecting pharmaceutical residues such as tetracycline and salicylate.

Event Title: Interview with Prof. Tsui Tsz‑ki, Martin

Summary of Event:

We consulted Professor Tsui Tsz‑ki, Martin, Associate Professor at The Chinese University of Hong Kong and an expert in environmental pollution, ecosystem biogeochemistry, and environmental health. With extensive experience in aquatic ecology and toxicology, he was invited to assess how our biosensor project Remedix could be developed in a scientifically rigorous and ecologically responsible way. The discussion covered the current status of antibiotic detection technologies, potential users and applications, technical and ecological challenges, and strategies for building reliability and trust around our system.

Key Insights:

• Local Environmental Context: Hong Kong wastewater plants often fail to remove all pharmaceutical residue. Integrating local pollution data will improve validation and relevance.
• Users and Applications: Beyond researchers, potential users include NGOs, community centers, and residents near polluted rivers — meaning our device must remain simple, accurate, and field‑ready for non‑experts.
• Technical Challenges: Complex water chemistry may alter color signals, especially under weather changes. Must confirm whether color intensity correlates linearly with antibiotic concentration and whether we can achieve a short reaction time. Non‑soluble antibiotics or those bound to particles may escape detection. Need to test if degradation products are also detected.
• Verification and Trust Independent lab testing, third‑party data, and government certification will be crucial to credibility. Clear communication with regulators and communities is essential.
• Cost and Labor: A cost comparison with traditional methods, showing time and labor reduction, will strengthen the case for adoption.
• Expansion: To monitor antibiotics in fish and seafood could benefit fisheries and food safety, alongside exploring active antibiotic degradation to aid pollution control.

Conclusion:

Professor Tsui's guidance was pivotal in highlighting the dual challenge of scientific rigor and practical usability. His emphasis on validation, ecological safety, and certification reinforces the importance of developing Remedix not only as a biosensor but as a trusted, sustainable solution. By situating our work within Hong Kong's pollution context and addressing global applications, his advice directed us to strengthen both the technical reliability and social relevance of our project.

Event Title: Interview with Professor Butaye and Miss Sandy Ng

Summary of Event:

Our team interviewed Professor Butaye and Miss Sandy Ng from City University to gain expert insights into antibiotic resistance and potential improvements for Remedix. Prof. Butaye explained that tetracyclines are widely used in the veterinary field because they are inexpensive and easily absorbed, whereas Aspirin (salicylate) are rarely used. He stressed that simply replacing tetracyclines with other antibiotics will not solve the resistance problem, as antibiotic overuse and incomplete absorption both contribute to environmental contamination.

Prof. Butaye also highlighted that resistance levels are already high and emphasized the importance of completing full antibiotic courses to avoid worsening the situation. He noted that public awareness of antibiotic resistance remains low, making education essential for both pet owners and the general public.

Regarding device design, he cautioned that calcium ions may interfere with tetracycline and affect detection accuracy. He also warned that the E. coli used in the beads could be killed by tetracycline, preventing proper detection. To overcome this, he suggested using tetracycline-resistant E. coli strains and further exploring tetracycline degradation mechanisms.

Key Insights:

• Veterinary Practices: Tetracyclines are common due to cost-effectiveness and easy absorption. Disposal of expired drugs should be regulated to prevent environmental contamination. Emotional factors affect proper antibiotic use in pet care, but incomplete treatments are less frequent than in humans.
• Antibiotic Resistance: Resistance levels are already high in both animals and humans. Unabsorbed antibiotics are excreted and reach the environment, worsening contamination. Raising public awareness about resistance and its health implications is crucial.
• Device Design Feedback: Calcium ions may react with tetracyclines, reducing detection accuracy. The sensing E. coli must be resistant to tetracycline to function properly. Tetracycline degradation should be further investigated.

Conclusion:

Prof. Butaye's feedback provided both scientific and practical guidance for refining Remedix. His insights underscored the urgent issue of antibiotic resistance in veterinary medicine, the need for public education, and technical improvements to ensure reliable detection. His recommendations pave the way for Remedix to become a more effective tool in combating antibiotic pollution and promoting responsible drug use.

Event Title: Interview with Fish Farm Owner Mr. Hui Chun‑yi, Johnny

Summary of Event:

We interviewed Mr. Hui Chun‑yi, Johnny, owner of Wing Lam Hydroponics Farm in Deep Bay, Lau Fau Shan, to gather firsthand perspectives on aquaculture wastewater practices. He highlighted critical regulatory gaps, noting that while government monitoring covers fish farming water, diluted wastewater is largely untested and sometimes reused for vegetable cultivation, raising food safety concerns. Mr. Hui emphasized the value of rapid, on‑site detection in intensive farming but also pointed out practical barriers, such as the need for costly equipment and technical expertise to prepare bacterial cultures and beads. At the same time, he recognized that reliable antibiotic residue detection could strengthen consumer trust in aquaculture products. His perspectives helped bridge the technical goals of our project with the practical realities of end‑users in the aquaculture industry.

Key Insights:

• Regulatory Gaps: Government monitoring is restricted to testing water used directly in fish farming, while diluted wastewater is not examined for antibiotic residues. In some cases, farms reuse discharged water for vegetable cultivation, which risks introducing harmful substances into the human food chain.
• Detection Technology: Rapid, on‑site detection is particularly valuable in intensive farming where frequent testing is necessary. preparing bacterial cultures and producing detection beads require specialized equipment and technical expertise that many farmers may not have, which could hinder widespread application. When invited to try making alginate beads without bacteria, he found it difficult to achieve uniform size, highlighting a barrier to reliability in farm settings.
• Consumer Assurance: Antibiotic residue detection can improve food safety and public confidence in aquaculture products.

Conclusion:

Mr. Hui's feedback emphasized the need for detection tools that are simple, affordable, and practical for farmers, while still ensuring food safety and consumer confidence. His insights highlighted both regulatory gaps and technical barriers, guiding us to refine Remedix into a more accessible and sustainable solution for aquaculture.

Event Title: Interview with Fish Farm Owner Mr. Law

Summary of Event:

We interviewed Mr. Law, owner of Choi Kee Fish Farm, to gain insights into antibiotic practices, wastewater management, and the practical challenges faced in aquaculture. Drawing from his long experience and participation in the Accredited Fish Farm Scheme, he explained how antibiotic use has decreased under stricter regulation, with farmers now adopting more natural supplements to strengthen fish health. He outlined the continued lack of clear protocols for wastewater disposal, where medicated water is still discharged into the sea, creating pollution concerns. Mr. Law also evaluated Remedix, valuing its low cost and usefulness, while pointing out technical barriers such as bacterial culturing. He suggested that automatic data reporting on antibiotic levels would make the device more impactful for farmers and the wider community.

Key Insights:

• Antibiotic Awareness and Use: under Accredited Fish Farm Scheme guidance, farmers use fewer antibiotics and rely more on natural supplements such as polysaccharides or herbal additives to boost fish immunity.
• Wastewater Disposal Gap: Despite tighter controls on antibiotic use, disposal practices remain problematic. Antibiotic‑treated water is typically purified for only a short period before being discharged into the sea, as no clear disposal protocols are provided. This results in long‑term pollution concerns.
• Accredited Fish Farm Scheme: The scheme enforces strict oversight on prescriptions, fish and water sampling, and quality checks on fry feed to avoid contamination. This raises standards but does not address the environmental risks of wastewater discharge.
• Feedback on Remedix: Mr. Law regarded Remedix as useful and low cost, which fits farmers' operational needs. He pointed out that culturing bacteria is beyond his expertise, which may limit adoption if technical steps remain complex.
• Project Suggestions: He suggested that Remedix automatically provide data on antibiotic concentrations within the water system. Such features would help both the fisheries sector and the wider community track contamination and reduce risks.

Conclusion:

Mr. Law's perspective demonstrated that while antibiotic use is more tightly regulated today, disposal gaps continue to threaten the marine environment. His appreciation of Remedix's affordability reinforces its potential value to farmers, but his concerns about technical barriers highlight the importance of a design that is simple and accessible. His suggestion for automatic data reporting strengthened our vision of Remedix as a transparent and practical tool for sustainable aquaculture and public trust.

Fluidic Modules Development

The mixing module. Prototype 3 shows successful mixing of viscous alginate solution (red) with blue dye solution. Forming a purple mixture.

The beads formation module. Prototype 3 produces beads with consistent size and shape.

System Design

The design of our system, with a bacterial culture unit, housing for the millifluidic modules to form alginate beads, detection unit for detecting the colour development of the beads and peristaltic pump for transferring the liquids. For details of the design and function please visit our hardware page.

Event Title: Interview with Professor Frank Lam Leung Yuk

Summary of Event:

We conducted an interview with Professor Frank Lam Leung Yuk from The Hong Kong University of Science and Technology, whose research focuses on environmental pollution treatment, nanotechnology, and electrocatalysis. The purpose of this consultation was to evaluate the technical feasibility and contextual relevance of Remedix within Hong Kong's environmental management framework. Prof. Lam provided insightful feedback on our system design, communication strategy, and its potential role in addressing pharmaceutical waste challenges.

Key Insights:

• Advised us to define clear user groups such as wastewater engineers, hospital staff, or farm operators to sharpen our deployment focus.
• Emphasized that antibiotic resistance is strongly influenced by overuse and improper disposal in human medicine, not just agriculture.
• Highlighted that hospital waste is well managed, but household and small-scale disposal remains poorly regulated.
• Suggested using pharmaceutical residues in municipal sewage as indicators for public misuse and policy monitoring.
• Encouraged us to expand from detection to active degradation using synthetic biology, positioning Remedix as both a diagnostic and remediation tool.

Conclusion:

Professor Lam's feedback helped us refine both the technical and strategic aspects of our project. His emphasis on focused user targeting, real-world deployment scenarios, and the need for integrated remediation has shaped the direction of Remedix as a scalable and practical platform for antibiotic monitoring and environmental mitigation.

Event Title: Interview with Professor Wu Peng

Summary of Event:

We interviewed Professor Wu Peng, Associate Professor in the Division of Epidemiology and Biostatistics at the University of Hong Kong. She teaches the introductory module on infectious diseases in the Master of Public Health curriculum. The purpose of the interview was to gain expert insight into public awareness, antibiotic use, and surveillance systems in Hong Kong, and to evaluate the potential of Remedix as both an educational and practical tool. Professor Wu offered practical and context-specific suggestions to improve the direction of our human practices work and the applicability of our device.

Key Insights:

• Suggested targeting students in educational settings to raise early awareness about antibiotic resistance.
• Emphasized the importance of understanding user motivation, why they would want or need to use the device.
• Advised conducting surveys to quantify the current level of public awareness and unfamiliarity with antibiotic resistance.
• Noted that antibiotic usage depends on the condition of the patient; different types and dosages are used accordingly.
• Mentioned that antibiotic usage in Hong Kong has remained relatively stable in recent years.
• Highlighted that overuse of antibiotics in human medicine is a major driver of antibiotic resistance.

Conclusion:

Professor Wu's input helped us better understand the societal and behavioral dimensions of antibiotic resistance in Hong Kong. Her recommendations encouraged us to define our user groups more clearly, use data to inform awareness strategies, and consider the practical deployment of Remedix in both educational and community settings. Her emphasis on surveillance, responsible prescription practices, and public engagement has shaped the way we frame and position our project in the broader context of antimicrobial resistance.

Event Title: Consultation with Prof. Chan Wing‑hong

Summary of Event:

We interviewed Prof. Chan Wing‑hong, Emeritus Professor of Chemistry at Hong Kong Baptist University, on two occasions to obtain expert advice on the scientific basis and future development of our Remedix prototype. With his expertise in analytical chemistry, biosensors, and materials science, Prof. Chan provided guidance on data validation, sensitivity, and environmental considerations. He also reviewed our millifluidics approaches, helping us overcome challenges in bead fabrication and laying the groundwork for automation. His feedback not only sharpened the technical direction of Remedix but also guided us in positioning the project within real‑world environmental and aquaculture contexts.

Key Insights:

• Detection Challenges: Real environmental samples have complex compositions that may alter tetracycline stability and signal response. Define degradation products of tetracycline and assess their environmental impact. Address both sensitivity and selectivity, demonstrating that Remedix can distinguish tetracycline signals in complex environments.
• Future Development: Expect tetracycline to undergo biodegradation in real systems (e.g., livestock waste), producing metabolites. Assess whether Remedix can detect these products. Current sensitivity is insufficient; consider adopting fluorescence‑based detection to enhance visibility and reach lower detection limits. Incorporate limitations of the prototype in future presentations to demonstrate awareness and credibility.
• Millifluidics Bead Formation: Enabled fabrication of uniform alginate beads at a scalable rate. Improved biosensor consistency and reliability. Established a foundation for automated bead production, essential for real‑world application.

Conclusion:

Prof. Chan's advice underscored both the potential and the current limits of our biosensor system. His recommendations on sensitivity, selectivity, and real‑world sample complexity reinforced the need for rigorous validation and future enhancements, such as fluorescence detection. His guidance on the engineering of our fluidic system significantly improved bead consistency and scalability, advancing us closer to practical application. Overall, Prof. Chan's insights strengthened the scientific rigor of our project while ensuring it develops into a reliable and implementable tool for aquaculture monitoring.

Event Title: Interview with Mr. MOK Wing-cheong, Director of the Hong Kong Drainage Services Department (DSD)

Summary of Event:

We had the privileged opportunity to interview Mr. MOK Wing-cheong, Director of the Drainage Services Department (DSD). It was an honour to engage directly with the city's leading authority in sewage treatment and environmental infrastructure. As the head of DSD, Mr. Mok possesses the most accurate and comprehensive data on antibiotic residues and medical waste pollution in Hong Kong's water systems. Our discussion offered essential insights into the current challenges of micro-pollutant removal, the policy gaps in regulating antibiotic discharge, and how Remedix—our antibiotic detection system—could bridge those gaps through scientific innovation and practical application. We also explored how to effectively communicate our solution to stakeholders through data-driven narratives and impactful visuals.

Key Insights:

• Antibiotic Pollution Issues: Micro-pollutants like antibiotics and microplastics are increasingly present in local rivers, including Kam Tin River. Illegal discharges and agricultural runoff are major contributors to high antibiotic levels in stormwater. Public health risks include bioaccumulation in seafood and environmental antibiotic resistance.
• Limitations of Existing Treatment Systems: Advanced technologies such as reverse osmosis and UV filtration are costly (up to USD$1.5/m³) and still fail to remove all micro-pollutants. Many private treatment facilities lack incentives to upgrade their existing membrane systems. Hong Kong's current standards lag behind international benchmarks (e.g., EU, Australia) for micro-pollutant removal.
• Evaluation of Remedix – Our Detection Solution: Strengths - Novel design using engineered E. coli beads for visual detection. Portable, scalable, and affordable—suitable for on-site monitoring with minimal infrastructure. Feedback - The concept is promising but must be backed by scientific evidence, including lab photos, specificity tests, and quantification data. False positives from environmental interference need to be addressed. Detection in clean water is more feasible at present than in complex wastewater.
• Implementation Considerations: Application Focus - Sewage treatment plants are preferred initial users due to their infrastructure and monitoring needs. Farms are less viable in the short term due to weak enforcement and low economic incentive. Technical Challenges - Bead regeneration and system durability must be optimized for field deployment. Long-term deployment requires cost-performance validation and integration into existing workflows.
• Future Development Path: Short-Term Goals - Focus on detecting antibiotics in relatively clean or pre-treated water. Optimize detection sensitivity (e.g., down to 1 PPB) and reduce false positives through improved bioengineering. Develop a clear, visual explanation of how the system operates. The system should consist of complete function in bacterial culture, generating beads and detection of the change in colour of the beads. Long-Term Vision - Explore integration of antibiotic degradation technologies. Conduct cost-benefit analyses for commercial scalability. Align development with upcoming environmental regulations, including the 2024-2027 agricultural licensing framework. As our product arouses public awareness of water pollution, we can gather data, analyze it and report back to the government for informed policymaking.

Conclusion:

Mr. Mok's insights as Director of DSD provided us with both policy-level perspective and technical expertise. His access to accurate pollution data, especially on antibiotics and medical waste, grounded our understanding in real-world conditions. This engagement reinforced the importance of coupling scientific innovation with regulatory awareness and data transparency. It also highlighted the need to communicate our work through clear visualizations, credible lab results, and a compelling environmental narrative. With this guidance, we are now better positioned to refine Remedix into a validated, scalable solution that addresses a pressing environmental health issue in Hong Kong and beyond.

Event Title: Interview with Prof. Benjamin J. Cowling

Summary of Event:

The team interviewed Professor Benjamin J. Cowling, Chair Professor of Epidemiology at the School of Public Health, The University of Hong Kong, and a member of the High-Level Steering Committee on Antimicrobial Resistance (AMR). The discussion centered on how to enhance the public health impact, design practicality, and affordability of the Remedix biosensing platform. Professor Cowling provided strategic and technical feedback to strengthen the project's alignment with Hong Kong's major antibiotic resistance challenges and the need for accessible, field-deployable monitoring systems.

Key Insights:

• Broader Spectrum Focus Recommended prioritizing the medical and healthcare sectors over agriculture, as clinical misuse of antibiotics remains a leading cause of resistance in Hong Kong.
• Policy Limitations: Highlighted governmental and operational challenges in controlling antibiotic use, particularly in private clinics where regulation is limited.
• Public Awareness: Emphasized the need to improve public understanding of pharmaceutical contamination and clearly communicate how antibiotic resistance affects everyday health and water safety.
• Design and Application: Suggested implementing Remedix in water treatment plants and drinking water systems to monitor antibiotic contaminants on a larger, real-world scale.
• Cost Considerations: Stressed the importance of developing a low-cost yet precise system to ensure sustainable adoption across both public health and environmental sectors.
• Enhanced Functionality: Inspired the idea of creating a fully integrated device that can culture bacteria, produce microbeads, and automatically detect color changes, allowing on-site and distributed testing in various locations such as hospitals, farms, and treatment facilities.

Conclusion:

Professor Cowling's advice significantly broadened the project's perspective, encouraging the team to design a comprehensive, automated biosensing platform that is affordable, effective, and scalable. His guidance directed the Remedix initiative toward addressing public health and antimicrobial resistance challenges through improved usability, real-time deployment, and community-level accessibility.

Event Title: Interview with Professor Chan Ping Lung

Summary of Event:

The team met with Professor Chan Ping Lung, an expert in microbial ecology and immunology, to discuss the design and application of the Remedix biosensor system. The conversation focused on validating E. coli performance, assessing practical testing methods, and understanding antibiotic contamination pathways in Hong Kong's aquatic environment.

Key Insights:

• Shelf Life and Monitoring: The expected shelf life of E. coli must be established under optimal storage conditions. Professor Chan suggested using camera-based monitoring to standardize and record colorimetric changes for more reliable data collection.
• Post-Test Analysis and Disposal: The development of AI-assisted image analysis is recommended to correct for color variations caused by lighting or camera differences, ensuring more accurate interpretation. Clear disposal guidelines must also be established to prevent E. coli release and potential environmental contamination.
• Antibiotic Contamination Context: Professor Chan explained that most antibiotics enter rivers through municipal sewage, often excreted unmetabolized. He highlighted the limitations of Hong Kong's Level 2 sewage treatment plants in removing chemical pollutants and noted that the inconsistency of Level 3 systems points to a need for further technological advancement. He also stressed the importance of public education, proper drug disposal, and recycling measures inspired by successful models such as Taiwan's drug management system.

Conclusion:

Professor Chan's feedback provides a strategic foundation for enhancing the Remedix project's scientific validity, environmental safety, and practical usability. His recommendations emphasized evaluating E. coli stability, integrating AI-assisted analysis, and developing environmentally responsible protocols. Furthermore, his broader insights on antibiotic contamination underscored the need to combine technological innovation, public awareness, and policy improvement to achieve sustainable water quality monitoring in Hong Kong.

Event Title: Interview with Pig Farm Owner Mr. Tang Yuk-hang, Ken

Summary of Event:

Our team interviewed Mr. Tang Yuk-hang, Ken, owner of a pig farm in Deep Bay, Lau Fau Shan, to learn about antibiotic use in pig farming and how Remedix could help. Mr. Tang explained that antibiotics are essential, especially for piglets, but overuse can cause residue buildup and resistance. Complete avoidance is impractical due to frequent disease risks. Although regular inspections by AFCD and veterinarians are conducted, farmers cannot easily monitor antibiotic levels in real time.

He expressed concern about antibiotic resistance and saw the need for tools that provide clearer information to optimize antibiotic use. Mr. Tang believed that Remedix could allow fast, low-cost residue detection, helping farmers control dosage, reduce overuse, and strengthen consumer confidence in local pork.

Key Insights:

• Detection and Application: Remedix's compact and low-cost design could facilitate on-site antibiotic residue detection. Rapid detection is valuable for intensive farming that requires frequent testing. Helps adjust dosage and prevents overuse. Enhances transparency and consumer trust in local farming.
• Concerns About Resistance: Farmers face difficulty keeping livestock healthy without antibiotics. Balancing vaccination, hygiene, and medication is essential. Better monitoring can reduce unnecessary antibiotic use.
• Detection Scope and Future Potential: Detection may currently be too focused on a limited set of contaminants. Expanding detection capabilities to include parameters such as oxygen levels or other pollutants would improve usability. Combining detection with degradation functions could save time and reduce treatment steps. A post-detection verification step could further ensure water safety.

Conclusion:

Mr. Tang Yuk-hang, Ken, believed that Remedix could help farmers manage antibiotics more effectively while improving food safety and consumer confidence. The device addresses a key gap in monitoring and contributes to safer, more sustainable pig farming.

Event Title: Interview with Professor Yan Meng and Dr. Chen Chong

Summary of Event:

The team interviewed Professor Yan Meng and Dr. Chen Chong from the State Key Laboratory of Marine Environmental Health, City University of Hong Kong. Both experts specialize in environmental science and pharmaceutical contamination monitoring. The discussion provided meaningful insights into how human behavior, policy shortfalls, and education influence antibiotic pollution and how the Remedix system can play a significant role in addressing these environmental challenges.

Key Insights:

• Public Involvement: Recommended focusing on human behavioral changes to reduce antibiotic pollution, as technological solutions for degradation and detection are still developing.
• Ecological Impact: Warned that antibiotic pollution can alter animal behavior and disrupt ecosystems, stressing the ecological risks involved.
• Policy Limitations: Pointed out insufficient government policies that lack focus on antibiotic pollution, slow decision-making, and limited persuasive testing measures.
• Public Education: Proposed clear disposal procedures for citizens, along with educational and advertising campaigns to encourage proper waste classification and antibiotic recycling.
• Application Opportunity: Encouraged the development of accessible testing technologies, such as portable biosensing systems like Remedix, to support on-site testing and raise community awareness about antibiotic contamination.

Conclusion:

Professor Yan Meng and Dr. Chen Chong's insights highlighted that resolving antibiotic pollution requires both advancements in detection technology and changes in public behavior. Their advice helped steer the Remedix project toward developing a practical, educational, and community-oriented solution, integrating science, awareness, and policy support to protect environmental and public health.

Event Title: Interview with Doctor Lau YB and Doctor Leung TK

Summary of Event:

Our team conducted an online interview with Doctor Lau YB (ICU) and Doctor Leung TK (Paediatrics) to understand medical perspectives on antibiotic use, pollution, and the application of Remedix. They noted that high tetracycline concentrations can kill E. coli, so strain selection must ensure the biosensor remains functional within safe concentration ranges. Both emphasized the need for secure transport and containment of E. coli beads to ensure biosafety and public trust.

The doctors pointed out that hospitals, poultry farms, and households all contribute to antibiotic pollution, mainly due to improper waste disposal. They questioned why our focus was limited to tetracycline and salicylate and suggested expanding detection to other pollutants, such as hormones and chemotherapy agents. They also explained that tetracycline is rarely prescribed to children, and antibiotic choice depends on patient and infection type.

Key Insights:

• Public and Social Issues: Public education and risk communication are needed to improve trust in treated water. Reliable transport and containment systems for E. coli-containing beads are essential for safe domestic use.
• Background Research: Identify sectors contributing most to pharmaceutical pollution: hospitals, farms, or households. Clarify the link between medical prescriptions and antibiotics detected in rivers. Reassess the selection of tetracycline and salicylate among potential pollutants.
• Awareness and Responsibility: Pharmacists instruct patients on proper antibiotic use and manage expired drugs. Hospital waste management is effective, but public misuse remains problematic.

Conclusion:

Dr. Lau YB and Dr. Leung TK's advice helped refine both the technical and social directions of Remedix. They encouraged expanding detection beyond tetracycline and salicylate, strengthening biosafety, and improving public communication. Their feedback reinforced the connection between medical practice, environmental protection, and responsible antibiotic management.