PEDOT coated microneedles towards electrochemically assisted skin sampling

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Minimally invasive skin sampling using microneedles (MNs) is gaining traction over traditional methods.
• Conventional metal MNs pose risks; organic conducting polymers (CPs) offer a safer, flexible alternative.

Purpose of the Study:

• To develop novel electrochemically assisted MNs for simultaneous skin biopsy and interstitial fluid (ISF) extraction.
• To utilize biocompatible CPs for enhanced MN performance and safety.
• To enable real-time monitoring of MN penetration depth and ISF salt analysis.

Main Methods:

• Fabrication of MNs using doped poly(3,4-ethylenedioxythiophene) coated on polymethyl methacrylate.
• Electrochemical techniques for real-time penetration depth assessment.
• X-ray photoelectron spectroscopy for analyzing extracted ions from ISF.

Main Results:

• Demonstrated successful extraction of ions from hydrated excised skin, paving the way for *in vivo* ISF extraction.
• Real-time monitoring of MN penetration depth was achieved.
• Identification of salts in ISF provides valuable chemical information.

Conclusions:

• Electrochemically assisted MNs using CPs provide a promising platform for minimally invasive skin sampling.
• Combined analysis of skin tissue biomarkers and ISF salt composition can improve disease diagnosis, such as in psoriasis.
• This technology expands diagnostic capabilities by integrating electrochemical sensing with chemical analysis.