Official websites use. Share sensitive information only on official, secure websites. Liposomes, sphere-shaped vesicles consisting of one or more phospholipid bilayers, were first described in the mids. Today, they are a very useful reproduction, reagent, and tool in various scientific disciplines, including mathematics and theoretical physics, biophysics, chemistry, colloid science, biochemistry, and biology. Since then, liposomes have made their way to the market.
Among several talented new drug delivery systems, liposomes characterize an advanced technology to deliver active molecules to the site of action, and at present, several formulations are in clinical use. Liposomes with modified surfaces have also been developed using several molecules, such as glycolipids or sialic acid. This paper summarizes exclusively scalable techniques and focuses on strengths, respectively, limitations in respect to industrial applicability and regulatory requirements concerning liposomal drug formulations based on FDA and EMEA documents.
Liposomes are small artificial vesicles of spherical shape that can be created from cholesterol and natural non-toxic phospholipids. Due to their size and hydrophobic and hydrophilic character besides biocompatibility , liposomes are promising systems for drug delivery. Liposome properties differ considerably with lipid composition, surface charge, size, and the method of preparation Table 1. For instance, unsaturated phosphatidylcholine species from natural sources egg or soybean phosphatidylcholine give much more permeable and less stable bilayers, whereas the saturated phospholipids with long acyl chains for example, dipalmitoylphos phatidylcholine form a rigid, rather impermeable bilayer structure [ 1 - 3 ].
Advantages and disadvantages of liposome [ [ 19 ]]. It has been displayed that phospholipids impulsively form closed structures when they are hydrated in aqueous solutions. Such vesicles which have one or more phospholipid bilayer membranes can transport aqueous or lipid drugs, depending on the nature of those drugs. Because lipids are amphipathic both hydrophobic and hydrophilic in aqueous media, their thermodynamic phase properties and self assembling characteristics influence entropically focused confiscation of their hydrophobic sections into spherical bilayers.
Those layers are referred to as lamellae [ 4 ]. Generally, liposomes are definite as spherical vesicles with particle sizes ranging from 30 nm to several micrometers. They consist of one or more lipid bilayers surrounding aqueous units, where the polar head groups are oriented in the pathway of the interior and exterior aqueous phases.
