Liposomes are nanodelivery systems, that are intensively studied for pulmonary drug delivery, because they are biocompatible and allow sustained action of drugs for local or systemic treatment with the possibility of targeted delivery. The purpose of this master thesis was a systematic review of literature to investigate preparation methods of liposomes and their properties, find out if drying liposomal dispersion improves stability or affect liposome integrity and to examine if liposomal formulations improve therapeutic efficacy. With the use of appropriate search profile in PubMed database we received 238 results between years 2012 and 2023. We applied inclusion-exclusion criteria and obtained 32 suitable scientific articles, which we examined in detail. We found out, that the most used model drugs were drugs for treating different lung infections. The most used method for liposome preparations was thin film method. Among the used organic solvents, the most common one was chloroform. Greater number of drugs were loaded into liposomes by passive loading. When active loading was used, researchers usually used the pH gradient method. We noticed that using the active loading method firmly improves encapsulation efficacy of hydrophilic drugs. In most researches, liposomes were homogenized to unify their size and lamellarity and to reduce their size. Using extrusion was more efficient than. For improving liposomal stability, especially at room temperature, conversion of liposomal dispersions into liposomal dry powders is highly recommended. Liposomes were converted to powder formulation using lyophilisation or spray drying. Excipients used for protection of liposomes during freeze drying and spray drying and for improving properties of formed dry powders were mostly mono- or disaccharides and amino acids. In in vivo studies, all but one liposomal formulation, were more efficient, safer and had prolonged effect of drugs compared to free drug formulations. We concluded that liposomes for pulmonary drug delivery are very promising drug delivery system to achieve sustained drug release or targeted delivery in lungs, especially if used as liposomal dry powders for inhalation and have a surface modification with targeting ligands. More liposomal medicines for pulmonary delivery are expected to get approved on marked, but more preclinical and clinical studies are demanded first.
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