Lipid nanoparticles coated with chitosan using a one-step association method to target rifampicin to alveolar macrophages

•Lipid nanoparticles coated with chitosan by association method show effective mucoadhesive profile.•Lipid nanoparticles promotes the controlled release of the drug in mucus layer.•Presence of chitosan promotes higher mucoadhesive properties and permeability.•Lipid nanoparticles loaded with rifampicin has potential to improve TB treatment. This work proposes the development and characterization of solid lipid nanoparticles (SLNs) loaded with rifampicin (RIF) aiming to enhance mucoadhesion of the SLNs and consequently internalization by the alveolar macrophages (AMs). The lipid nanoparticles (NPs) were characterized and the results showed that the NPs obtained present a spherical or a starry shape with diameter around 250−500 nm, a monodisperse population, with zeta potential between −31 mV for uncoated SLNs and +33 mV for coated SLNs. The drug EE was approximately 90 % and the loading capacity (LC) 4.5 %. The SLNs coated with chitosan by the association method (aC-SLNs) show an effective mucoadhesive profile, verified by the turdimetry and surface loading method, corroborated with the cellular assays. The presence of chitosan in the aC-SLNs promotes higher mucoadhesive properties to the NPs and permeability in A549, suggesting that the safe aC-SLNs-RIF can be used as a promising drug delivery system for improving tuberculosis treatment.