Separable Microneedle for Integrated Hyperglycemia Sensing and Photothermal Responsive Metformin Release

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Diabetes management requires continuous glucose monitoring and precise drug delivery.
• Existing methods often lack integration and real-time feedback for effective hyperglycemia control.
• There is a critical need for advanced theranostic microdevices for diabetes care.

Purpose of the Study:

• To develop a separable double-layer microneedle (DLMN) patch for theranostic applications in diabetes.
• To enable in situ glucose detection in interstitial fluid and controllable metformin release for hyperglycemia regulation.
• To evaluate the efficacy of the DLMN patch in a preclinical model of type 2 diabetes.

Main Methods:

• Fabrication of a DLMN patch with a GelMA supporting base for glucose sensing and a phase-change material (PCM) arrowhead for drug delivery.
• Incorporation of a Cu-TCPP(Fe)/glucose oxidase composite for colorimetric glucose detection via a cascade reaction.
• Encapsulation of melanin nanoparticles and metformin in the PCM layer, activated by near-infrared light for controlled drug release.

Main Results:

• The DLMN patch successfully extracted dermal interstitial fluid and provided a visible colorimetric readout of glucose levels.
• The PCM layer demonstrated a near-infrared photothermal response, enabling controllable release of metformin.
• Application in a streptozotocin-induced type 2 diabetic rat model showed effective hyperglycemia regulation.

Conclusions:

• The developed DLMN patch serves as an integrated portable colorimetric sensor and self-regulated glucose-lowering system.
• This theranostic microneedle technology shows significant potential for improving daily diabetes management.
• The device offers a promising platform for future advancements in wearable diabetes care solutions.