Chemically imaging living cells by scanning electrochemical microscopy
Allen J Bard1, Xiao Li, Wei Zhan
1Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, TX 78712, United States. asn@mail.utexas.edu
Biosensors & Bioelectronics
|June 27, 2006
Summary
Scanning electrochemical microscopy (SECM) offers high-resolution analysis of biological interfaces. This technique effectively monitors cellular processes and detects electroactive substances in living cells and cell models.
Area of Science:
- Electrochemistry
- Microscopy
- Biophysical Chemistry
Background:
- Scanning electrochemical microscopy (SECM) provides high-resolution interfacial analysis.
- Its application to biological systems, especially living cells, is an area of growing interest.
Purpose of the Study:
- To describe the general principles of SECM.
- To discuss diverse applications of SECM in biological systems.
- To highlight SECM's utility in probing cellular functions and viability.
Main Methods:
- Electrochemical detection and monitoring using SECM.
- Application of SECM to hepatocytes, bacteria, HeLa cells, and giant liposomes.
- Utilizing SECM for tracking redox-active compounds and cellular responses.
Main Results:
- Detection and electrochemical monitoring of thiodione during menadione treatment of hepatocytes.
- Following the antimicrobial effects of silver(I) on bacterial respiration via SECM.
- Demonstration of ferrocenemethanol (FcMeOH) accumulation and oxidation feedback in HeLa cells for viability assessment.
- Successful probing of giant liposomes with encapsulated redox compounds using SECM.
Conclusions:
- SECM is a versatile technique for high-resolution probing of biological interfaces.
- It enables the detection of electroactive substances and monitoring of cellular functions.
- SECM shows significant potential for applications in cell biology and biomedical research.
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