Amperometric ion-selective nanoelectrodes for bioanalytical sensing and imaging

Area of Science:

• Electrochemistry
• Nanotechnology
• Bioanalytical Chemistry

Background:

• Traditional potentiometric methods have limitations for in-vitro and in-vivo ion analysis.
• Amperometric ion-selective nanoelectrodes represent an emerging electrochemical technique for bioanalysis.
• These nanoelectrodes combine selective ion sensing with high spatial resolution imaging.

Purpose of the Study:

• To review recent applications of amperometric ion-selective nanoelectrodes in bioanalytical sensing and imaging.
• To highlight the advantages of amperometric nanoelectrodes over potentiometric methods.
• To introduce the principles of amperometric nanoelectrodes and nanoscale scanning electrochemical microscopy (SECM).

Main Methods:

• Utilizing amperometric ion-selective nanoelectrodes for electrochemical ion sensing.
• Employing nanoscale SECM for high-resolution ion imaging (down to 30 nm).
• Fabricating biocompatible ion-selective nanopipets and micropipets for in vivo applications.

Main Results:

• Demonstrated nanoscale SECM imaging of molecular transport at single nuclear pore complexes.
• Visualized chemical interactions among single bacterial cells.
• Showcased detection of bacterial carbonate production and neurotransmitter acetylcholine (in-vitro and in-vivo).

Conclusions:

• Amperometric ion-selective nanoelectrodes are powerful tools for advanced bioanalytical sensing and imaging.
• Their high biocompatibility and fabrication simplicity facilitate in vivo studies.
• These nanoelectrodes enable unprecedented insights into biological systems at the nanoscale.