The influence of cholesterol on the interaction between N-dodecyl-N,N-dimethyl-N-benzylammonium halides and phosphatidylcholine bilayers.

Effects of N-dodecyl-N,N-dimethyl-N-benzylammonium halides (DBeAX) on thermotropic phase behavior of phosphatidylcholine/cholesterol bilayers as well as on 1H NMR spectra were studied. The surfactants were added either to the water phase or directly to the lipid phase (a mixed film was formed). The benzyl group, opposite to liposomes without cholesterol, is not incorporated into the bilayer in the gel state but only in the liquid state.

A study on the interaction between 1-decyloxymethyl-3-carbamoylpyridinium salts and model membranes--the effect of counterions.

The interaction between 1-decyloxymethyl-3-carbamoylpyridinium salts (PS-X) and two types of vesicles (multilamellar vesicle and sonicated vesicle) was investigated. Vesicles were formed from two classes of phospholipids: 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine (DPPE). The PS-X salts used had nitrate, perchlorate, tetrafluoroborate and halides as counterions.

Interaction between N-dodecyl-N,N-dimethyl-N-benzylammonium halides and phosphatidylcholine bilayers-the effect of counterions.

The interaction of N-dodecyl-N,N-dimethyl-N-benzylammonium halides (DBeAX) with two types of phospholipid vesicles (MLV and SUV) was investigated using DSC and 1H NMR. It was suggested that the benzyl group like the micellisation process (J. Colloid Interface Sci.

The effect of selected anions on dipalmitoylphosphatidylcholine phase transitions.

The effect of three anions, Cl-, Br- and I-, on the phase transitions of dipalxnitoylphosphatidyicholine (DPPC) was measured. Main phase transition was modestly affected by these anions in the salt concentration range 0.2 M.

Counterion effects on interaction of amphiphilic quaternary ammonium salts with model membranes.

The micellization as well as the interaction with model membranes of dodecyltrimethylammonium halides (DTAX) and N-dodecyl-N,N-dimethyl-N-benzylammonium halides (DBeAX) were studied at 298K and 313K by means of titration calorimetry. The calorimetric curves reflect both the counterion and benzyl group effects on the interaction of the surfactants studied with the lipid bilayer. Bromide as counterion enhanced the interactions more than chloride of both DTAX and DBeAX compounds with model membranes.