Chemical imaging for in situ detection and discrimination of aquatic toxins targeting voltage gated sodium channels
EMSL Project ID
60667
Abstract
The focus of this study is to determine the detection sensitivity for neurotoxin activity using an engineered human cell line cultivated in the System for the Analysis at the Liquid Vacuum Interface (SALVI). In-situ/in-operando time-of-flight secondary ion mass spectrometry ToF-SIMS will be used to characterize cell membrane compositional changes elicited by neurotoxins with different mechanisms of sodium channel inactivation. Neurotoxins, chemicals that are harmful to the nervous systems of animals, produced by aquatic microorganisms are a global health, national security, and economic challenge. To detect neurotoxins, there are several approaches to either categorize neurotoxin or assess their activities; however, they are either too specific, such as PCR and antibody-based enzyme linked immunosorbent assays, which require live animals like the mouse bioassay, and/ or require time-consuming and expensive sample preparation prior to analysis using LC-MS/MS and HPLC. Furthermore, many of the common methods employed today depend upon identifying toxins based on known sequences or known toxin structure and thus miss toxins that may be structurally different but have the same activity.We propose cell-based biosensor approach, specifically identifying voltage-gated sodium channel activities of cell membrane caused by neurotoxin. Our first approach would be the chemical imaging techniques, such as but not limited to structure illumination microscopy (SIM), confocal laser scanning microscopy (CLSM) and fluorometric-based activity assays, which will provide additional membrane biomarkers that could be used to detect neurotoxin activity. The next step would be to determine the specificity of these cell membranes and chemical biomarkers in environmental water samples. We’ll transition to exposing our cells in the SALVI device to more complex mixtures of toxin-producing organisms in culture as well as environmental water samples. This effort will lead to developing a prototype microfluidic device for detecting neurotoxins in aquatic environments.
Achieving these specific aims will demonstrate the potential of this new microfluidic system to not only be used to detect neurotoxins but also other chemical or pathogen insults. Our approach does not depend on prior knowledge of toxin identity or structure as it assesses the mechanisms and effect of neurotoxin activity on a cell.
This work address key aspects of the Environmental Transformation and Interactions Science Area. One aspect is developing a “rapid and sensitive activity-based assay to screen for neurotoxins in environmental water samples”, and this cell-based microfluidic system “can detect and identify the activity of sodium-channel-impacting neurotoxins in aquatic environments.” Neurotoxins, chemicals that are harmful to the nervous systems of animals, produced by aquatic microorganisms are a global health, national security, and economic challenge. Overall, this work is relevant to EMSL’s mission of focusing on “the mechanistic and predicative understanding of environmental microbial, plant and ecological process in above and belowground ecosystems,…”
Project Details
Start Date
2023-01-17
End Date
2023-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members