Researchers have developed a ground-breaking coaxial microelectrode probe that integrates the strengths of two powerful imaging techniques. By combining scanning electrochemical microscopy (SECM) and scanning electrochemical cell microscopy (SECCM), this device offers unprecedented resolution for dry surface analysis. This flexible design overcomes traditional limitations, such as sample heterogeneity and low collection efficiency. Consequently, the probe enables high-sensitivity detection across various industrial and medical applications.

Enhancing Diagnostics with the Coaxial Microelectrode Probe

The innovative probe utilizes a stable, renewable nanoliter-scale electrochemical droplet cell. This construction allows for long-term and large-area imaging of surface morphology and conductivity. Furthermore, confining reactions within a small droplet significantly boosts tip-collection efficiency. As a result, the device achieves superior spatial resolution compared to conventional microelectrodes. Significantly, the probe minimizes errors related to multisample heterogeneity, ensuring more reliable data in complex environments.

High-Precision Forensic Applications

One of the most impressive applications involves the high-throughput detection of alkaline phosphatase (ALP) activity. Researchers used the probe to analyze authentic blood fingerprints at various storage intervals. By measuring enzyme activity, they established a time-since-deposition (TSD) estimate with a remarkable 97% accuracy. Therefore, this technology could revolutionize forensic investigations by providing precise timelines for biological evidence found at crime scenes.

What is a coaxial microelectrode probe?

A coaxial microelectrode probe is a specialized analytical tool that combines a central ultramicroelectrode with an external micropipette. This dual-function design allows researchers to perform high-resolution electrochemical imaging and localized chemical analysis simultaneously.

How does the probe improve forensic blood analysis?

The probe detects the activity of enzymes like alkaline phosphatase within blood fingerprints. Because this activity changes over time, the device can estimate the exact time since the blood was deposited with approximately 97% accuracy, which is vital for criminal investigations.

Disclaimer: This content is for informational and educational purposes only and does not constitute medical advice. Refer to the latest local and national guidelines for clinical practice.

References

1. Liu L et al. Bridge SECM and SECCM with a Coaxial Microelectrode@Micropipette Probe. Anal Chem. 2026 Mar 30. doi: 10.1021/acs.analchem.5c05020. PMID: 41913082.
2. Zerdoumi R et al. Integration of Scanning Electrochemical Microscopy and Scanning Electrochemical Cell Microscopy in a Bifunctional Nanopipette toward Simultaneous Mapping of Activity and Selectivity in Electrocatalysis. Anal Chem. 2024 Jul 9;96(27):10886-10892. doi: 10.1021/acs.analchem.4c00149.
3. Zhang M et al. SECM for imaging and detection of latent fingerprints. Anal Chem. 2009 Jan 15;81(3):1038-44. doi: 10.1021/ac802319m.