Tuning Pore Sizes of Core-Shell Dendritic Mesoporous Silica Nanoparticles for Efficient Loading of Functional...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Precise control over pore accessibility in dendritic mesoporous silica nanoparticles (DMSNs) is crucial for applications involving large biomolecules and nanoparticles.
• Existing synthesis methods may lack scalability or fine-tuning capabilities for pore structure.

Purpose of the Study:

• To present a scalable anion-assisted synthesis for tuning pore size and shell thickness in DMSNs.
• To investigate the effect of the core-to-silane ratio on pore architecture and guest molecule loading.
• To establish a practical framework for designing DMSNs with hierarchical pore structures.

Main Methods:

• Utilized an anion-assisted synthesis with sodium salicylate to modify DMSNs.
• Varied the core-to-silane ratio to control pore size (eliminating small mesopores, preserving large interwrinkle mesopores) and shell thickness.
• Performed loading experiments with silver nanoparticles and lysozyme to assess guest uptake.

Main Results:

• Achieved tunable shell thicknesses from ~19 nm to 151 nm for nano- and microscale DMSNs.
• Demonstrated that increasing core content suppresses small mesopores, favoring large interwrinkle mesopores (12-21 nm).
• Showcased significantly higher lysozyme loading (4.1 ± 1.1 mg m⁻²) in particles with large, accessible mesopores, indicating diffusion limitations over surface area.

Conclusions:

• The core-to-silane ratio is a robust parameter for engineering hierarchical pore architectures in DMSNs.
• Optimized DMSNs with large, accessible mesopores enhance loading capacity for nanoscale guests like enzymes and catalysts.
• This approach provides a practical framework for designing advanced mesoporous materials for diverse applications.