Lab-on-a-Paper for Point-of-Use Microbial Source Tracking

Water contamination with microbial organisms in water systems, including drinking, ground, recreational, and wildlife, is a global issue. Even with well-operated drinking-water treatment plants, such as those available in Scotland and the UK, drinking water distribution systems are vulnerable to episodic pathogen intrusion (from pressure losses, repairs or rain-induced run-off of dirty water), presenting high risks to human health and significant economic losses. For example the Centre for Disease Control in the United States (one of the safest drinking water systems in the world) estimate that there are 4-32 million cases of acute gastrointestinal illness per year from public drinking water systems. Contamination is also impacting local distribution systems with decentralised facilities, such as those present in many low and middle-income countries (LMICs) as well as remote areas of 'developed' countries (such as Scotland). In this Fellowship, low-cost, deployable paper-based biosensor devices (lab-on-a-paper) will be developed for the online monitoring of water quality.

Using sensors built around simple and low-cost paper-based devices to process water samples, we will develop rapid, sensitive and easy-to-use testing devices that can detect genetic markers of pathogens, along with co-markers of their origins, a key capability to identify multiple pathogens in drinking water and track their source. For example, the detection of human DNA markers could potentially infer a human faecal contamination, while animal genes (e.g. cattle, pig, etc...) could help identify agricultural sources. By deploying these portable sensors, we will obtain data on contamination patterns and dynamics, which in turn will provide the ability to not only rapidly respond to the contamination and curtail it before consumption of drinking water, but also design new surveillance systems and build new understandings of the pathways taken by the contaminating pathogens in the environment.

The detection of microbial contamination together with its tracing and tracking in the environment is currently performed mainly by isolating, culturing and identifying the pathogens against known contaminants, through a long process that can take many days and extensive technical expertise. New procedures have been improved to enable faster testing via the molecular detection of specific genetic markers or the pathogens (< 1 hour), but these currently require centralised facilities and skilled personnel, preventing their use in the field. The technologies developed in this Fellowship will allow the detection of multiple genetic markers rapidly, in the field. These highly multiplexed assays will provide the capability for industry to provide a rapid and dynamic response to a contamination, and to identify and track its source.

Working with Scottish Water, we will validate the devices in the field in Scotland. Our close collaboration will ensure that the developments are relevant to the end-users, such that the translation into practical use can be accomplished with minimal delay and risk. This will have the potential to enable "sustainable communities and sustainable homes", an initiative of Scottish Water for small rural communities which is particularly important in Scotland as well as affording opportunities for growth internationally.

Beyond rural communities in high-resources settings, decentralised water systems are also present in low and middle-income countries. Through interactions with NGOs, we will aim to explore the impact of the technologies developed in this Fellowship in the wider community, globally.

In future, our biotechnological platform will also enable source tracking and monitoring in the wider environment (e.g. agricultural processes), including antimicrobial resistance, thus providing a cornerstone in solving challenges arising to maintain a healthy population, a key strand of the UK Industrial Strategy.