Soft Sub-Structured Multi-Material Biosensor Hydrogels with Enzymes Retained by Plant Viral Scaffolds

Area of Science:

• Biomaterials Science
• Nanotechnology
• Biosensor Development

Background:

• Development of stable and reusable biosensors is crucial for various applications.
• Immobilization of enzymes is key to preventing diffusion and maintaining activity.
• Viral nanorods offer a scaffold for enzyme display and integration into matrices.

Purpose of the Study:

• To create an all-soft multi-material combination for biosensing.
• To demonstrate the application of enzyme-decorated viral nanorods within a hydrogel matrix as a biosensor.
• To investigate methods for surface modification and matrix cross-linking for stable enzyme immobilization.

Main Methods:

• Surface modification of poly(ethylene glycol) (PEG) hydrogels with isothiouronium or thiol groups.
• Cross-linking of gelatin methacryloyl (GM) spots for surface anchoring.
• Conjugation of enzymes (horseradish peroxidase, penicillinase) to tobacco mosaic virus (TMV) and integration into GM spots.

Main Results:

• Spatially defined GM spots containing enzyme-conjugated TMVs were successfully created on PEG hydrogels.
• Immobilized enzymes on TMV within GM spots showed sustained activity after 7 days of washing.
• Penicillinase-conjugated TMVs retained activity after 22 months of dry storage, outperforming free enzymes.

Conclusions:

• The integration of enzyme-coupled TMV into hydrogel matrices provides a versatile approach for reusable biosensor components.
• This multi-material system prevents enzyme diffusion and maintains long-term activity.
• The developed biosensor platform shows promise for analyte-specific detection.