Background:
Tetrodotoxin (TTX) is a biosynthesized neurotoxin that exhibits powerful anticancer
and analgesic abilities by inhibiting voltage-gated sodium channels that are crucial for cancer
metastasis and pain delivery. However, for the toxin’s future medical applications to come true, accurate,
inexpensive, and real-time in vivo detection of TTX remains as a fundamental step.
Methods:
In this study, highly purified TTX extracted from organs of Takifugu rubripes was injected
and detected in vivo of mouse organs (liver, heart, and intestines) using Cyclic Voltammetry (CV) and
Square Wave Anodic Stripping Voltammetry (SWASV) for the first time. In vivo detection of TTX was
performed with auxiliary, reference, and working herring sperm DNA-immobilized carbon nanotube
sensor systems.
Results:
DNA-immobilization and optimization of amplitude (V), stripping time (sec), increment (mV),
and frequency (Hz) parameters for utilized sensors amplified detected peak currents, while highly sensitive
in vivo detection limits, 3.43 µg L-1 for CV and 1.21 µg L-1 for SWASV, were attained. Developed
sensors herein were confirmed to be more sensitive and selective than conventional graphite rodelectrodes
modified likewise. A linear relationship was observed between injected TTX concentration
and anodic spike peak height. Microscopic examination displayed coagulation and abnormalities in
mouse organs, confirming the powerful neurotoxicity of extracted TTX.
Conclusion:
These results established the diagnostic measures for TTX detection regarding in vivo
application of neurotoxin-deviated anticancer agents and analgesics, as well as TTX from food poisoning
and environmental contamination.