This research will develop and test a novel sensor designed to detect and quantify algal toxins (cyanotoxins) frequently found in freshwaters. The presence of high concentrations of cyanotoxins in several freshwaters, some of which serve as sources of drinking water supplies, seriously threatens human and environmental health. This project aims to address the urgent need of rapid monitoring and quantification of microcystins in surface waters experiencing algal blooms. Microcystins are a group of frequently found cyanotoxins in freshwaters experiencing problems of harmful algal bloom formation. The investigators will develop highly-selective and fast-responding sensors for the detection and quantification of microcystins in drinking water and sources of drinking water supplies using advanced carbon nanomaterials.
This proposal aims to create nanostructured biosensors for selective identification and quantification of microcystins. With this objective, two specific aims are targeted: 1) demonstrate nanostructured sensors for point-of-use determination of microcystins, and 2) validate sensor performance with real-world water samples. The sensor will be based on an interdigitated array electrode structure inside a microfluidic channel; advanced carbon nanomaterials such as 3D graphene and carbon nanotubes will be coated on the electrode to provide nanostructured detection of microcystins. These nanomaterials are advantageous for sensor purposes; they provide high electrical conductivity and increased surface area. The sensor selectivity will be provided by bioreceptors specific to different microcystin isoforms. The nano-biosensor will employ electrochemical measurement techniques such as Electrochemical Impedance Spectroscopy (EIS). The fabricated device will be evaluated for its ability to detect and quantify microcystins in natural surface water obtained from various freshwater aquatic systems that experience severe occurrence of cyanobacterial harmful algal blooms (cyano-HABs). This study will also provide a fundamental understanding of the principles for creating nano-biosensors used in selective identification and quantification of microcystins. The project has a strong societal impact. First, this collaborative research and educational activities through this project will provide a significant contribution to the field of nano-biosensing for monitoring water quality. Second, it addresses a serious and emerging environmental problem that is associated with the presence of the highly toxic microcystins in natural waters. Finally, the nanotechnology-based biosensors introduced in this research can be further developed for in-situ monitoring of microcystins, which have been repeatedly reported to occur in some of the Great Lakes, several other US and international lakes and rivers. This will have a tremendous implication for managing sources of drinking water and protecting human health. These efforts can be complementary to other on-going efforts towards the restoration and sustainability of surface aquatic systems. In addition, the research activities will directly advance the knowledge and understanding while promoting teaching, training and learning by bringing together a research team of graduate students, undergraduate students, postdoctoral fellows and faculty. Several activities will enhance education on cyanotoxins. These include (i) rigorous cross-disciplinary laboratory training for students in different programs, resulting in the enrichment of the curriculum, (ii) collaborative research opportunities for scientific training to the student researchers, (iii) broad dissemination of results, (iv) enhanced public awareness of topics relevant to Cyano-HABs and cyanotoxins, and (v) strengthened interdisciplinary research collaborations.