Mempro™ Liposome Preparation by Sonication

Creative Biostructure has committed to the liposome research and development in recent years, and we have developed a comprehensive Mempro™ Liposome platform to provide high-quality products and the best services to our worldwide clients. Liposome preparation services are the core part of Mempro™ Liposome Technology. Among various advanced techniques, sonication method is widely used to produce custom liposomes.

Figure 1. TEM images of liposomes prepared by extrusion (a) and sonication (b). (M. M. Lapinski, et al., 2007)

In sonication system, the sample should not to be heated above the phase transition temperature since the high energy input. High-intensity sonication is based on the propagation of sound waves with frequencies between 16 and several hundred kHz through an aqueous dispersion of polar lipids. More...(The propagation of the sound wave through the media results in the spontaneous generation and collapse of small cavities, a process better known as cavitation. The cyclic formation and destruction of cavities causes extreme pressure and temperature rises inside the cavity and highly turbulent flow conditions in close proximities to the collapsing cavities. The turbulent flow conditions exert high shear forces on large pro-liposomes, particles that are spontaneously formed upon contact of the dry free-flowing lipid with aqueous media. Eventually, these forces are high enough to cause a disruption of the pro-liposomal structures followed by a reformation of smaller, less stress-susceptible vesicles. Generally, there are ways to perform sonication method: immersing the tip of a sonicator into a liposome dispersion or placing a sample in a tube/beaker into a bath sonicator. To prepare SUVs or MLVs on a small scale, tip sonication is preferred. The MLVs can be broke up into smaller vesicles by the induced pressure.)

Figure 2. Two types of sonication to prepare liposomes

Liposome preparation by sonication or extrusion shows different advantages depended on the application of liposome. More...(Extrusion involves subjecting a sample of large liposomes through cylindrical pores of filters uniform in size, resulting in a homogenous population of smaller vesicles with vesicle sizes correlating to the size of the applied filters. Compared to extrusion method, the primary advantage of sonication method is less time-consuming. Whereas, the reproducibility of the resulting liposome made by sonication batch to batch is not as better as made by extrusion.)

Figure 3. Comparison of Sonication and Extrusion

Besides sonication method, Creative Biostructure also provides various methods such as thin-film, freeze-thawing, extrusion, freeze-drying rehydration, and reverse phase evaporation to produce custom liposomes based on Mempro™ Liposome Technology. Creative Biostructure is the most professional and reliable partner to facilitate your liposome research. Please feel free to contact us for a detailed quote.

References:
N. Cho, et al. (2013). Comparison of Extruded and Sonicated Vesicles for Planar Bilayer Self-Assembly. Materials, 6: 3294-3308.
A. Parise, et al. (2015). Preparation, characterization and in vitro evaluation of sterically stabilized liposome containing a naphthalenediimide derivative as anticancer agent. Drug Deliv, 22(5): 590–597.
M. M. Lapinski, et al. (2007). Comparison of Liposomes Formed by Sonication and Extrusion: Rotational and Translational Diffusion of an Embedded Chromophore. Langmuir, 23: 11677-11683