Sense and Purify : Detect, Destroy and Remove Water Contaminants – Sense and Purify, SPy

We have designed the electrochemiluminescent sensor system for detecting pathogens. The Consortium has: 1. Created electrodes whose surface is modified with immobilised antibodies 2. Demonstrated selective capture of E. coli from water samples. 3. Functionalised secondary antibodies with luminescent dyes and allowed them to bind to the captured E. coli bacteria. 4. Generated electrochemiluminescence whose brightness depends on the concentration of E. coli present in the water sample. Boron Doped Diamond (BDD) electrodes have been characterised and optimised for the determination and electro-decomposition of nevirapine (NVP) and tenofovir (TNF). Cyclic voltammetry (CV) was used to study the amperometric responses for nevirapine and tenofovir drugs in phosphate buffer (PB) and Britton-Robinson (BR) buffer as electrolytes. We haves made significant progress on the use of UV-Vis spectroscopy as a cost effective, real time approach to monitoring the concentration of the parent pharmaceuticals (primarily anti-cancer drugs) and for monitoring their degradation over time. We also focused on the synthesis of the molecular ECL luminophores and especially dye doped silica nanoparticles (DDSN) as luminescent sensors for application in ECL-based assays for targeted pollutants. DDSN have proven to be stable, non-toxic and efficient ECL based probes. The synthetic strategy for DDSN relies on the co-condensation of alkoxysilane bearing dyes with silica precursors in presence of surfactants yielding the desired DDSN. We modelled the hydroxyl radical concentration profiles around the BDD particles to identify the optimum concentration of particles in suspension relative to the concentration of the organic pollutant. We have investigated the hydroxyl radical concentration as a function of distance from the particle surface where the contaminant concentration varies from 1.0 ?M to 0.25 M

The programme has been very successful during the first 18 months. For example, we have developed new electrochemiluminescent dyes that generate light when an appropriate potential is applied, and a co-reactant is present. These dyes have been used to create a new antibody based electrochemiluminescent sensor that can detect as few as 100 E. coli bacteria in one millilitre of water! Boron Doped Diamond (BDD) electrodes have been explored for the simultaneous detection and destruction of pharmaceuticals, e.g., antiretrovirals, that are challenging to remove using conventional approaches. We have made significant progress to optimise the composition of the BDD particles in order to maximise the rate at which the hydroxyl radicals are produced which decompose the pollutants. These systems are capable of decomposing recalcitrant organic pharmaceuticals, such as the anti-cancer drugs doxorubicin and gemcitabine, within six hours! We have also developed in silico models of the radical generation process that are guiding the design of the reactor.

The ultimate objective of the programme is to create a reactor with integrated sensors/spectroscopy that measures the pollutants in the incoming water stream, decomposes organics within the water while monitoring the efficiency of the treatment and produces water that can either be reused within the manufacturing process, e.g., pharmaceutical or food production, or discharged. This programme directly impacts UN SDG Goal 6: Ensure access to water and sanitation for all. The ability to locally produce clean water from wastewater for industry or drinking at low capital and operating cost is very significant. To enhance innovation capacity and integration of new knowledge prototype reactors will be demonstrated for the treatment of production wastewaters from the food (NU) as well as pharmaceutical industries (DCU). We are also impacting on education through a series of measures including school visits, public outreach articles and social media.

One publication in international peer reviewed journal.
One publication focused on general public.
Eight school visits.