Chitosan nanoparticle-loaded mannitol microspheres: structure and surface characterization.

Area of Science:

• Materials Science
• Nanotechnology
• Pharmaceutical Sciences

Background:

• Mannitol microspheres are promising for pulmonary drug delivery due to favorable aerodynamic properties.
• Chitosan/tripolyphosphate nanoparticles are utilized for encapsulating therapeutic proteins.

Purpose of the Study:

• To characterize the surface and internal structure of spray-dried mannitol microspheres containing chitosan/tripolyphosphate nanoparticles.
• To confirm the successful encapsulation and distribution of nanoparticles within the microspheres.

Main Methods:

• Spray-drying was used to prepare mannitol microspheres.
• Confocal laser scanning microscopy, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry were employed for characterization.

Main Results:

• Mannitol was found to be distributed throughout the microspheres.
• Chitosan nanoparticles were homogeneously mixed with mannitol within the microspheres.
• Both mannitol and nanoparticles were detected on the microsphere surface, with mannitol predominating.

Conclusions:

• Chitosan nanoparticles are successfully encapsulated within mannitol microspheres.
• The homogeneous distribution of nanoparticles is confirmed, ensuring uniform delivery of nanoencapsulated therapeutic macromolecules.
• These findings support the use of these microspheres for pulmonary protein delivery.