Liposomes
“Liposomes are artificially prepared vesicles made of lipid bilayer. Liposomes can be filled with drugs, and used to deliver drugs for cancer and other diseases. Liposomes can be prepared by disrupting biological membranes, for example by sonication. Liposomes can be composed of naturally derived phospholipids with mixed lipid chains (like egg phosphatidylethanolamine) or other surfactants. Liposomes should not be confused with micelles and reverse micelles composed of monolayers.” (Wikipedia, Liposomes, 7/28/2011
“Aptamers are oligonucleic acid or peptide molecules that bind to a specific target molecule. Aptamers are usually created by selecting them from a large random sequence pool, but natural aptamers also exist in riboswitches. Aptamers can be used for both basic research and clinical purposes as macromolecular drugs. Aptamers can be combined with ribozymes to self-cleave in the presence of their target molecule. These compound molecules have additional research, industrial and clinical applications.” (Wikipedia, Aptamers, 7/28/2011)
Recent Journal Articles
Stability of anionic liposome-cationic polymer complexes in water-salt media
(430-435) Colloid Journal 73 #3 (2011)
Yaroslavovet al of Moscow State University, Moscow, showed that polycation adsorption is accompanied by the neutralization of charges on liposomes and their aggregation. The subsequent addition of a low-molecular-weight salt (NaCl) solution to suspensions of complexes causes them to dissociate into their initial components, while the stability of the complexes with respect to the salt action increases with the fraction of the anionic lipid in the liposome membranes. The data obtained are interpreted from the position of the formation-disintegration of a molecular capacitor, the charge of which is generated by spatially separated anionic lipids located in the bilayer membrane and cationic units of the adsorbed polyamine. (RDC 8/2/2011)
Aptamers-in-Liposomes for Selective and Multiplexed Capture of Small Organic Compounds
( 1169–1173)Macromolecular Rapid Communications 32 #15 (2011)
Kim et al, South Korea and Turkey used liposomes with aptamers with their own binding buffer. When small, organic, toxic compounds in water pass through a liposome barrier, only the target molecules are captured by the DNA aptamers inside the liposomes. The capture efficiency is not high when DNA aptamers are used in tap water. When DNA aptamers in liposomes are used, the capture efficiency increases more than 80%. The simultaneous and selective elimination of target toxicants is successfully performed for tap-water samples containing toxicant mixtures. (RDC 7/27/2011)