Liposomes as Drug Carriers: Classification, Preparation Methods, and Medicinal Use

Liposomes are one of the most well-known and promising nanoscale drug delivery systems. Liposomal medicinal products are successfully used in clinical practice for cardiovascular, oncological, dermatological, and other indications. The development of liposomes and their widespread implementation in clinical practice are relevant tasks.

The aim of the study was to summarise and analyse scientific data regarding the structure, composition, and classification of liposomes, as well as specific aspects of liposome production methods.

This review covers up-to-date information on marketed liposomal medicinal products. The authors illustrate how production methods affect the composition and structure of liposomes. The size and lamellarity are important characteristics of liposomes that determine the encapsulation efficiency and biodistribution of active pharmaceutical ingredients (APIs). The choice of excipients depends on the intended use of liposomal medicinal products. The article summarises the main liposome production methods, highlighting specific usage aspects, advantages and disadvantages. Conventional liposome production methods are easy to apply and do not require complex equipment, and their principal disadvantages include the low efficiency of API encapsulation within liposomes and the high complexity of scaling up technological processes. The authors pay special attention to microfluidic techniques for liposome preparation, which are characterised by a highly controlled technological process (in terms of size distribution and lamellarity), high reproducibility, and scalability to the level of industrial production and are applicable to encapsulating different APIs.

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