Porous Cellulose Nanofiber-Based Microcapsules for Biomolecular Sensing

Area of Science:

• Biomaterials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Cellulose nanofibers (CNFs) offer desirable properties for sensing applications, including renewability and biodegradability.
• Current CNF sensing platforms are primarily 2D (nanopaper, hydrogels), limiting in situ and in vivo applications.
• Advanced CNF structures are needed to enhance flexibility and sensing performance for early disease diagnostics.

Purpose of the Study:

• To develop robust, porous, and hollow CNF-based microcapsules for advanced sensing applications.
• To utilize primary plant cell wall components (CNF, pectin, xyloglucan) for microcapsule fabrication.
• To demonstrate the potential of these microcapsules in biosensing, particularly for glucose detection.

Main Methods:

• Fabrication of porous and hollow CNF microcapsules using CNF, pectin, and xyloglucan.
• Assessment of dextran molecule diffusion through the microcapsule wall.
• Encapsulation and cross-linking of glucose oxidase (GOx) enzyme within the microcapsules.
• Immobilization of GOx-loaded microcapsules onto various surfaces for glucose sensing.

Main Results:

• Successfully synthesized robust, porous, and hollow CNF microcapsules.
• Demonstrated controlled diffusion of dextrans (70 kDa and 2000 kDa) into the capsules.
• Achieved high encapsulation efficiency (68 ± 2%) for glucose oxidase (GOx).
• Successfully measured glucose concentrations up to 10 mM using immobilized microcapsules.

Conclusions:

• Developed a novel CNF-based microcapsule platform for biosensing.
• The microcapsule design minimizes mass transport limitations, enhancing response times.
• This technology offers potential for simple, efficient, and disposable analytical devices in healthcare, diagnostics, and environmental monitoring.