2026-09-23T07:10:00Zhttps://iris.unica.it/oai/requestoai:iris.unica.it:11584/2658662025-02-14T00:34:48Zcom_11584_207615com_11584_111066col_11584_265854
Chitosan and PLGA microspheres as drug delivery system against pulmonary mycobacteria infections
MANCA, MARIA LETIZIA
Chitosan
Cytotoxicity
Encapsulation
Stability
Microparticle
Mucoadhesion
Nebulization
PLGA
Rifampicin
Settore CHIM/09 - Farmaceutico Tecnologico Applicativo
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.
2007-02-28
info:eu-repo/semantics/doctoralThesis
https://hdl.handle.net/11584/265866
eng
numberofpages:134
info:eu-repo/semantics/openAccess
Università degli Studi di Cagliari
license:Non specificato