A Microneedle-Based Electrochemical Sensor with Multiplex Detection in Physiological Environment and Incorporated in...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Materials Science

Background:

• Increasing prevalence of disorders linked to calcium (Ca²⁺) and potassium (K⁺) deficiencies.
• Existing diagnostic methods often require time-consuming blood sampling.
• Need for rapid, non-invasive diagnostic tools for early detection.

Purpose of the Study:

• To develop a portable microneedle-based device for simultaneous detection of Ca²⁺, K⁺, and pH.
• To enhance sensor stability, reliability, and accuracy using a novel passivation layer (Arcare).
• To validate sensor performance in artificial interstitial fluid (ISF) and complex media.

Main Methods:

• Fabrication of microneedle sensors modified with Poly-(3,4-ethylenedioxythiophene) (PEDOT) and ion-selective membranes (ISMs).
• Surface characterization using electrochemical methods, Raman Spectroscopy, and Scanning Electron Microscopy (SEM).
• Multiplexed detection of ions and pH using a Portable Unit Lab-on-Site Electrochemistry (PULSE) platform.

Main Results:

• Demonstrated linear responses and high reliability (r² > 0.9) for Ca²⁺ and K⁺ detection.
• Confirmed stable and accurate ion detection across varying pH levels.
• Successfully validated the sensor's performance in complex media with reduced interference.

Conclusions:

• The developed microneedle sensor enables accurate, real-time, multiplexed detection of key analytes.
• The portable device offers a promising non-invasive alternative to traditional blood tests.
• Highlights potential for advanced wearable health monitoring systems.