Nanoscale physics

Impact of carbon nanotubes on HDL - like structures – computer simulation study
Pabiszczak M.1, Gorny K.1,2, Raczynski P.1,2 and Gburski Z.1,2 
1 Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland 
E-mail: przemyslaw.raczynski@us.edu.pl
2 Silesian Centre of Education & Interdisciplinary Research, 75 Pułku Piechoty 1a, 41-500 Chorzów, Poland

High denisty lipoproteines (HDL) are complex aggregates composed of mulitple proteins, phospholipids, triglicerydes, cholesterol and cholesterol esters. HDL aggregates transport excess cholesterols from cells into the liver, thus are important factor concerning atherosclerosis and other cardiovascular events [1]. Liposomes and HDL – like structures can also be considered as drug carriers [2], thus studying their molecular and mechanical properties is of great interest form both scientific and applied point of view.
In our recent studies we have investigated the process of nanoindentation of phosphoilipid bilayer by various nanotubes [4,5]. In this work we present the results of molecular dynamics (MD) simulations of nanoindentation of HDL- like structure by carbon nanotubes. The simulated lipoprotein consists of POPC phospholipids, cholesterols, single APO-E molecule and is filled with cholesterol oleate. Constant velocity puling method was applied to stud the force and work required to insert carbon nanotube into the HDL aggregate. 

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