Acta chimica Slovenica

Cholesterol protects phosphatidylcholine liposomes from N,N-dimethyl-1-dodekanamine N-oxide influence.

PMID 26085426


The interaction of N,N-dimethyl-1-dodekanamine N-oxide (C12(CH3)2NO) with egg yolk phosphatidylcholine (EYPC) liposomes containing cholesterol (CHOL) was studied. The perturbation of CHOL-EYPC bilayers in unilamellar liposomes (ULL) was observed by the leakage of fluorescent probe calcein. Weak leakage is observed at low surfactant concentration cC12NO (minimal perturbation of the bilayer) followed by an intensive leakage at a middle cC12NO (creation of pores). No change in fluorescence intensity was measured at high cC12NO (calcein totally released from liposomes). The higher CHOL amount in the bilayer, the more surfactant is needed to create pores in the bilayer. Solubiliazation of CHOL-EYPC ULL induced by C12NO was studied turbidimetrically. The solubilization curve consists of three parts: saturation of bilayer at low cC12NO (liposomes are preserved), followed by solubilization (liposome - mixed micelle transition) and post-solubilization. The c12NO concentration needed for the onset of the soubilization raises with the increase of nCHOL:nEYPC. The structure of liposomes is still preserved at total calcein release for all nCHOL:nEYPC.