Chitosan and PLGA microspheres as drug delivery system against pulmonary mycobacteria infections

Various types of rifampicin (RIF)-loaded microparticles were compared for their stability during nebulization. Poly(lactide-co-glycolide) (PLGA), chitosan (CHT) and PLGA/CHT microparticles (MPs) were prepared by emulsion, precipitation or spray-drying techniques. MPs ability to be nebulized (NE%) as well as stability during freeze-drying or/and nebulization (NEED%), were evaluated after RIF extraction from MPs and determination by light spectroscopy. MP mean diameters and zeta-potential values were measured by dynamic light scattering, morphology was assessed by SEM, cytotoxicity by MTT method and mucoadhesive properties by mucin association. In all cases, freeze-drying prior to nebulization did not affect EE%, NE or NEED%. In CHT, MPs RIF encapsulation efficiency (EE%) decreased with increasing CHT concentration (viscosity) and CHT-MP NEED% was higher when the polymer was crosslinked by glutaraldehyde. PLGA MPs, exhibited both higher RIF EE% and also higher nebulization ability and NEED%, compared to CHT ones, but also higher cytotoxicity. However, when the two polymers were combined in the PLGA/CHT MPs, EE%, NE% and NEED% increased with increasing MP CHT-content. PLGA/CHT MPs with 0.50% or 0.75% CHT exhibited highest EE% for RIF and also best nebulization ability and stability, compared to all other MP formulations studied. Additionally they had good mucoadhesive properties and comparably low cytotoxicity.

Grantor dc:publisher

Università degli Studi di Cagliari

Year dc:date

2007

Author dc:creator

• MANCA, MARIA LETIZIA

• Chitosan
• Cytotoxicity
• Encapsulation
• Stability
• Microparticle
• Mucoadhesion
• Nebulization
• PLGA
• Rifampicin
• Settore CHIM/09 - Farmaceutico Tecnologico Applicativo

Statement dc:rights

• info:eu-repo/semantics/openAccess
• license:Non specificato

Language dc:language

eng

Handle dc:identifier

https://hdl.handle.net/11584/265866

OAI identifier oai:identifier

oai:iris.unica.it:11584/265866