Ethanol injection method

A disadvantage of the ethanol injection method to produce SUV is the need to use a low lipid concentration, resulting in a low encapsulation efficiency of the aqueous phase. The dispersions can be concentrated by ultracentrifugation, ultrafiltration, or removal of water by evaporation. 

The mixed liposomal solutions were prepared by the ethanol-injection method(13) in order to obtain completely transparent solutions. It is interesting to note that miscibility of the photochromic amphiphiles with DPPC depend on the position of bulky azobenzene. If azobenzene is incorporated close to the end of long alkyl chain, a stable mixed bilayer state cannot be formed. On the other hand, when the azobenzene moiety is located near the head group or at the center of the hydrocarbon tail, the azobenzene amphiphiles are successfully incorporated into the bilayer membrane. No individual micelle formation nor phase separation in the bilayer was observed at 25 °C by absorption spectroscopy. However, the microstructure of the mixed liposomes depends on the type of azobenzene amphiphiles. 

In the procedure utilized by Oberholzer and Luisi (2002) all ingredients are added to a solution in which the vesicles are being formed by the ethanol injection method,... 

Gimatecan)-containing liposomes prepared by the ethanol injection method. J. Lipos. Res., 14, 87-109. 

The manufacturing of nanosized liposomes can be performed using the methods mentioned above. However, the small size of nanoliposomes is difficult to achieved by methods such as film hydration. Molecular self-assembly occurs in the injection method, and then the size and morphology of obtained liposomes can be well controlled. In fact, liposomes that result from the injection method are uniform and small enough, to the nanoscale, and usually SUVs are obtained. Because of the very low toxicity of ethanol, the ethanol injection method is usually used and is described as follows to show the process of manufacturing liposomes [50]. A scale-up manufacturing process of the ethanol injection method has been established [80-82], The obtained liposome size is mostly less than 300 nm ... 

Wagner, A., Vorauer-Uhl, K., Kreismayr, G., and Katinger, H. (2002), The crossflow injection technique—An improvement of the ethanol injection method, J. Liposome... 

Stano, P. Bufali, S. Pisano, C. Bucci, F. Barbarino, M. Santaniello, M. Carminati, P. Luisi, P.L. Novel campo-tothecin analogue (gimatecan)-containing hposomes prepared by the ethanol injection method. J. Liposome Research 2004,14 (1 2), 87-109. 

Cationic liposomes composed of 3(3- [ N- (N N-dimethylaminoethane (carbamoyl] cholesterol (DC-Chol) and dioleoylphosphatidylethanolamine (DOPE) (DC-Chol/DOPE liposome, molar ratio, 1 1 or 3 2) prepared by the dry-film method have been often used as non-vtral gene delivery vectors. We have shown that a more efficient transfection in medium with serum was achieved using DC-Chol/DOPE liposomes (molar ratio, 1 2) than those (3 2), and preparation method by a modified ethanol injection than the dry-film. The most efficient DC-Chol/DOPE liposome for gene transfer was molar ratio (1 2) and prepared by a modified ethanol injection method. The enhanced transfection is related to an increase in the release of DNA in the cytoplasm by the large lipoplex during incubation in opti-MEM 1 reduced-serum medium (optiMEM), not to an increased cellular association with the lipoplex. Cationic liposomes rich in DOPE prepared by a modified ethanol injection method will help to improve the efficacy of liposome vector systems for gene delivery. 

Key words Cationic liposome. Gene transfection, DOPE, DC-Chol, Ethanol injection method. 

MEI method of liposome preparation is similar to the reported ethanol injection method (16, 17), proliposome preparation (17, 18), and coacervation methods (19). The differences... 

Cationic liposome (DC-Chol/ DOPE=l 2) and a modified ethanol injection method to prepare liposomes, increased gene expression. Int J Pharm 342 33-39... 

Maitani Y, Soeda H, Wang J, Takayama K (2001) Modified ethanol injection method for liposomes containing (3-sitosterol (3-D-glucoside. J Liposome Res 11 115-125... 

Two important aspects of Uposome formation must be emphasized here. First, in some cases we observe the formation of ordered supramolecular structures starting from a chaotic disordered mixture of surfactants (as in the ethanol injection method . As noticed before, this increase of order is attended by a simultaneous increase of water entropy and a decrease of overall free energy (Upids and solvent). Secondly, every time a liposome forms, there is the anergence of a division, with an inside world that is different from the external environment, even if the two worlds actually interact with each other. The discrimination between inside and outside, appUcable to lipid vesicles, is the first structural pre-requisite for the living cell. It is therefore clear that lipid or fatty acid vesicles may be considered relevant experimental model of simplified cells, and their role on... 

DNA, coding for the GFP was introduced in liposomes composed by POPC, together with the whole T T machinery (T7 RNA polymerase and E. coli cell extracts). GFP was synthesized inside vesicles prepared by the ethanol injection method. 

Zou L-Q, Liu W, Liu W-L, Liang R-H, Li T, Liu C-M et al. Characterization and bioavailability of tea polyphenol nanoliposome prepared by combining an ethanol injection method with dynamic high-pressure microfluidization. J Agric Food Chem. 2014 62(4) 934-941. 

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