Probing the nanostructure, interfacial interaction, and dynamics of chitosan-based nanoparticles by multiscale...

Area of Science:

• Nanotechnology
• Materials Science
• Biophysics

Background:

• Chitosan nanoparticles (NPs) are crucial for drug delivery, gene therapy, and medical imaging.
• Understanding NP internal morphology, nanostructure size, interface, and dynamics is vital for precise design and effective biological applications.
• A multiscale, nondestructive analytical technique is needed for examining NPs.

Purpose of the Study:

• To present a novel multiscale solid-state Nuclear Magnetic Resonance (NMR) approach.
• To investigate the internal morphology, nanostructure size, interfacial interactions, and dynamics of chitosan-poly(N-3-acrylamidophenylboronic acid) NPs.

Main Methods:

• Solid-state NMR spectroscopy, including 13C multiple cross-polarization magic-angle spinning (MAS) for composition and conformation.
• 1H spin-diffusion with 13C detection and theoretical simulations for morphology and size.
• 1D MAS and 2D triple-quantum MAS 11B NMR for interfacial interactions.
• Dynamic-editing 13C MAS and 2D 13C-1H wide-line separation for dynamics.

Main Results:

• Quantitative determination of NP composition and detection of chitosan conformational changes.
• Quantitative determination of internal morphology and nanostructure size.
• Revelation of interfacial coordinated interactions between chitosan and phenylboronic acid.
• Detailed insights into NP dynamics in solid and swollen states.

Conclusions:

• The developed multiscale solid-state NMR approach is effective for characterizing chitosan-based NPs.
• A model of the NPs' unique nanostructure, interfacial interaction, and dynamics was proposed.
• This technique is crucial for advancing nanotechnology and the precise design of NPs for biological applications.