[Electric capacitance of bilayer lipid membranes from hydrogenated egg lecithin during phase transition from liquid crystalline state to gel]. / Elektricheskaia emkost' bisloinykh lipidnykh membran iz gidrirovannogo iaichnogo letsitina pri fazovom perekhode iz zhidkokristallicheskogo sostoianiia v gel'.

The electrical capacity of planar bilayer lipid membranes (BLM) from natural hydrogenated egg lecithin (HEL) in n-decane at a temperature of phase transition was measured. The temperature of phase transition was determined calorimetrically to be 51 degrees C. The data obtained revealed a phase separation of HEL in BLM into two fractions, one freezing at 42-44 degrees C and one that is converted to a liquid-crystal state at 51-59 degrees C. It was assumed that the first fraction is rich in dipalmitoyl lecithin, and the second fraction is rich in distearoyl lecithin. Freezing and the transition to the liquid-crystal state were accompanied by an increase and decrease in membrane thickness, respectively, in part due to a displacement of the solvent from the torus to the planar part of the bilayer. The displacement of the solvent is explained by changes in the disjoining pressure in BLM, which arises across the lipid bilayer due to van der Waals forces of attraction between water layers on both sides of the BLM.

[Kinetics of resealing of lipid pores]. / Kinetika zatekaniia lipidnykh por.

The resealing of lipid pores in BLM at the temperature of phase transition was studied. It is show that the size of a pore correlates with the time of its resealing. The correlated coefficient of pore diffusion is close to that of lipid molecules in the gel state.

[Exponential distribution of interimpulse current intervals in lipid bilayer membrane at phase transition temperature]. / Eksponentsial'noe raspredelenie mezhimpul'snykh intervalov toka v bisloinykh lipidnykh membranakh pri temperature fazovogo perekhoda.

The statistical analysis of current fluctuations in unmodified bilayer lipid membranes at the phase transition temperature was made. An exponential distribution of current fluctuations was revealed.

[Lipid pores and life time of lipid bilayer membranes in gel and liquid crystal states]. / Lipidnye pory i vremena zhizni bisloinykh lipidnykh membran v gel'- i zhidkokristallicheskom sostoianiiakh.

The lifetime of lipid bilayer membranes formed from hydrogenated egg lecithin has been studied at the phase transition from liquid crystalline state to the gel. It was shown the lowering of the membrane stability at the phase transition temperature of hydrogenated egg lecithin. Using lifetime values and measured surface tension of bilayer the critical radius of transmembrane pore has been evaluated in comparison with experimental data, obtained by transmembrane current fluctuation registration. It was shown that lifetimes of bilayer lipid membrane in gel state conform data, derived from Deryagin-Gutop-Prokhorov's theory. The radii of pores corresponded to maximal transmembrane current fluctuations are close to critical values of pores in the gel state.