Syntheses and characterization of liposome-incorporated adamantyl aminoguanidines

Abstract

A series of mono and bis-aminoguanidinium adamantane derivatives has been synthesized and incorporated into liposomes. They combine two biomedically significant molecules, the adamantane moiety and the guanidinium group. The adamantane moiety possesses the membrane compatible features while the cationic guanidinium subunit was recognized as a favourable structural feature for binding to complementary molecules comprising phosphate groups. The liposome formulations of adamantyl aminoguanidines were characterized and it was shown that the entrapment efficiency of the examined compounds is significant. In addition, it was demonstrated that liposomes with incorporated adamantyl aminoguanidines effectively recognized the complementary liposomes via the phosphate group. These results indicate that adamantane derivatives bearing guanidinium groups might be versatile tools for biomedical application, from studies of molecular recognition processes to usage in drug formulation and cell targeting.

Adamantane in Drug Delivery Systems and Surface Recognition

“…Results from recent work in our laboratory—including the studies of adamantyl tripeptides, adamantyl glycopeptides, and adamantyl guanidines, their incorporation into liposomes and interaction with the liposome bilayer as an artificial biological membrane [ 31 , 32 ]—prompted us to review the use of the adamantyl group in designing new targeted drug delivery systems and their application in drug-membrane interaction studies.…”

Application of 4-amino-N-adamantylphthalimide solvatochromic dye for fluorescence microscopy in selective visualization of lipid droplets and mitochondria

“…The aggregation of the DPPC liposomes due to the presence of amphiphilic adamantyl compounds has been reported. [38] However, polydispersion of liposomes observed by DLS may partly be due to the aggregation of 1.…”

Adamantyl ferrocene derivatives: Antioxidant abilities and effects on model lipid membranes

“…Our previous research of biologically active adamantoylated compounds has been focused on their interaction with model biological membrane. [20][21][22] Although the effect of ferrocene on liposome has not been studied intensively, several recent papers have described the application of oxidized ferrocene as an organometallic amphiphile and ferrocene-modified phospholipid in preparation of the redox-modified liposomes. [58,59] They are capable to target cancer cells and selectively trigger the release of incorporated drug using the electrochemical activity of a ferrocene-modified phospholipid.…”

“…Our previous research of adamantane derivatives of biologically active peptidoglycan fragments has shown their strong interaction with lipid membrane . Furthermore, we have shown that the adamantyl moiety can be employed as an anchor in the lipid bilayer while the polar part of the molecule, a carbohydrate mannose or guanidine residue, is exposed on the liposome surface …”

“…[20] Furthermore, we have shown that the adamantyl moiety can be employed as an anchor in the lipid bilayer while the polar part of the molecule, a carbohydrate mannose or guanidine residue, is exposed on the liposome surface. [21,22] On the other hand, ferrocene is a neutral, chemically stable and nontoxic molecule with a unique structure as well as an excellent redox property, allowing for its wide applications in chemistry. [23,24] It can be easily derivatized and functionalized or oxidized to ferricenium salts.…”