Microneedle-Integrated Device for Transdermal Sampling and Analyses of Targeted Biomarkers

Area of Science:

• Biomedical Engineering
• Sensor Technology
• Point-of-Care Diagnostics

Background:

• Existing point-of-care systems lack seamless sensor integration for body fluid analysis.
• Minimally invasive methods are crucial for user safety and reducing infection risk.

Purpose of the Study:

• To design and develop a disposable microscale device for interstitial fluid (ISF) extraction.
• To integrate simultaneous monitoring of glucose, lactate, and potassium ions (K+) within the device.
• To evaluate the device's performance for point-of-care diagnostic applications.

Main Methods:

• A 3D-printed cap-like structure with a microneedle (MN) array for ISF extraction (≈3.0 μL).
• Utilized negative pressure convection technology for efficient fluid withdrawal.
• Incorporated bioreceptor-modified carbon fiber (CF) electrodes for selective analyte detection.

Main Results:

• Demonstrated selective detection of glucose, lactate, and K+ with high sensitivities and low detection limits.
• Achieved high sensitivities: 0.258 μA μm⁻¹ cm⁻² (lactate), 0.549 μA μm⁻¹ cm⁻² (glucose), 0.657 μA μm⁻¹ cm⁻² (K+).
• Validated performance through ex vivo testing on porcine skin, showing accurate ISF biomarker detection.

Conclusions:

• The developed microscale device offers a compact, self-contained, and user-friendly solution for ISF analysis.
• It presents a significant advancement over current point-of-care diagnostic methods.
• The device shows potential for widespread adoption in clinical settings for real-time health monitoring.