Next-Generation Low-Cost Electrochemical Biosensors for Water Quality Monitoring

Improving wastewater monitoring is critical for detecting microbial pathogens and parasites because wastewater reflects the health status of entire populations. Pathogens such as bacteria, viruses, and protozoa can persist in sewage and act as early indicators of community-wide infections. Antibiotic contamination of wastewater can lead to development of resistance. Traditional clinical surveillance often misses asymptomatic carriers or underreports cases. In contrast, wastewater-based epidemiology (WWBE) offers a non-invasive, cost-effective means of tracking infection trends across large populations in real time. However, current detection methods are often resource intensive, slow and can lack sensitivity, making them inadequate for rapid public health decision-making. With the growing threat of antimicrobial resistance (AMR) and emerging zoonotic diseases underscoring the urgency for more responsive and precise monitoring tools. Wastewater can act as both a reservoir and transmission route for AMR genes, enteric viruses, and resilient parasites like Cryptosporidium, posing serious risks to water quality and human health. Effective monitoring allows for early intervention, risk assessment, and informed policy actions to prevent outbreaks and safeguard water systems. Without enhanced surveillance technologies, such as real-time sensors or multiplex detection platforms, public health authorities may continue to rely on outdated data, hampering rapid response to evolving microbial threats. In addition, the presence of antibiotics in the water system is of significant concern too. Wastewater from hospitals, households and agricultural origins will often contain antibiotics and drug-resistant bacteria, which can facilitate horizontal gene transfer and amplify resistance in microbial communities. These resistant strains can cause downstream contamination of surface and groundwater, posing risks to human and animal health. Monitoring their presence in wastewater is essential for tracking the emergence of AMR, assessing environmental exposure, and informing mitigation strategies. From an analytical perspective, laser induced graphene (LIG) electrodes offer exceptional sensitivity and performance, are highly manufacturable and can be easily combined with microfluidic systems for sample handling and delivery. Additionally, when combined with aptamer receptors, these sensors offer a 'multi omic' measurement capability with the potential to detect small molecules (antibiotics) and antigens or whole pathogens (bacterial, viral and protozoan). We propose to combine LIG sensors with the multifunctional detection capability, low-cost potential, manufacturability and high stability of aptamers to unlock a suite of easy to produce, highly sensitive and stable LIG aptasensors for common wastewater measurement challenges. The project will focus on refining SELEX produced aptamer sequences with an AI based approach to produce a low-cost, portable and user friendly multiplexed LIG aptasensor which address a range of water relevant measurements. The project will focus on the following: 1)           Developing a LIG electrode, aptamer attachment chemistry, advanced 2D material engineering for biosensor fabrication, and fluidic accessory for water sampling and analysis 2)           AI driven refinement of SELEX derived aptamer sequences to provide a suite of bioreceptors for the project 3)           Make exemplar measurements with a range of wastewater relevant targets a.           Detection of E.coli with an aptamer modified LIG sensor b.           Detection of two antibiotics (ciprofloxacin and sulfamethoxazole) with an aptamer modified LIG sensor c.           Detection of SARS-CoV-2 with an aptamer modified LIG sensor d.           Detection of Cryptosporidium oocysts with an LIG aptasensor 4)           Benchmarking of the sensor performance against gold standard techniques 5)           Creation of an advanced prototype platform which includes sensor, reader, sample addition and data handling capability followed by in the field validation studies.