Monitoring the Activity and Inhibition of Cholinesterase Enzymes using Single-Walled Carbon Nanotube Fluorescent Sensors

Dan Loewenthal, School of Chemistry, Tel Aviv University, Tel Aviv, Israel (dan.loewenthal@chem.ox.ac.uk)
Dotan Kamber, Department Of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
Gili Bikser, Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel

Cholinesterase enzymes are involved in a wide range of bodily functions, and their disruption is linked to pathologies such as neurodegenerative diseases and cancer. While cholinesterase inhibitors are used as drug treatments for diseases such as Alzheimer and dementia at therapeutic doses, acute exposure to high doses, found in pesticides and nerve agents, can be lethal. Therefore, measuring cholinesterase activity is important for numerous applications ranging from the search for novel treatments for neurodegenerative disorders to the on-site detection of potential health hazards. Here, we present the development of a near-infrared (near-IR) fluorescent single-walled carbon nanotube (SWCNT) optical sensor for cholinesterase activity and demonstrate the detection of both acetylcholinesterase and butyrylcholinesterase, as well as their inhibition. We show sub U L–1 sensitivity, demonstrate the optical response at the level of individual nanosensors, and showcase an optical signal output in the 900–1400 nm range, which overlaps with the biological transparency window. To the best of our knowledge, this is the longest wavelength cholinesterase activity sensor reported to date. Our near-IR fluorescence-based approach opens new avenues for spatiotemporal-resolved detection of cholinesterase activity, with numerous applications such as advancing the research of the cholinergic system, detecting on-site potential health hazards, and measuring biomarkers in real-time.

Anal. Chem. 2022, 94, 41, 14223–14231

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Short Biography of Presenting Author

2022 - Present - PhD Student, Physical Chemistry (University of Oxford, Kukura group - mass photometry)

2020 - 2022 - M.Sc, Physical Chemistry (Tel Aviv University, Bisker group - single-walled carbon nanotube fluorescent sensors, magna cum laude)

2018 - 2022 - Israel Institute for Biological Research (Department of Analytical Chemistry - small molecule mass spectrometry)

2014 - 2018 - B.Sc, Natural Science (Israel Open University)

Awards

Clarendon Scholarship (Oxford University, 2022)

Lincoln Kingsgate Scholarship (Lincoln College - Oxford University, 2022)

Best Poster (Analytical and Bioanalytical Chemistry Conference, 2020)