The Study Of The Interaction Of Lipoparticle With Gaint Vesicle

Giant vesicles is composed of a monolayer phospholipid bilayer,it is widely used in the theory simulation of the biomembrane system,for example,phase separation,membrane fusion and endocytosis.Lipoparticle is an emerging tool of nano drug carrier,it is an assembly of lipid shell surrounding nanoparticle core.There is a significant advantage for lipoparticle in gene therapy and cancer treatment.In this article,we mainly investigate the interaction of lipoparticle with giant vesicle in solvent by using the self-consistent field theory method.In Chapter 1,we briefly introduce biological membrane experimental model and the research progress of biological membrane self-organization in recent years.We also introduce the self-consistent field theory(SCFT)in the application research of biological membrane.SCFT as a coarse graining model,can well reflect the biological membrane phospholipid molecules amphipathy,effective shape and the flexibility of chain,etc.Therefore,this article using the self-consistent field theory to study behavior of membrane.In Chapter 2,we study the interaction of lipopaticle with giant vesicle.We discuss the impact of hydrophilic fraction and nanoparticle size on the system free energy.When the hydrophilic fraction is changed,a lot of interesting structural transformation can be obtained in the interstage.For example,stalk phase,HD phase and vesicle leakage(HII phase or IMI phase).There is a little effect on morphology changing the radius of nanoparticles.In addition,we calculate the free energy of the system quantitatively.According to the system free energy,the interaction between lipoparticle and giant vesicle is a spontaneous process.It is need to overcome an energy barrier for the new morphology in the interaction,and the energy barrier is increasing with the increasing of hydrophilic fraction or nanoparticle radius.In Chapter 3,we study the interaction between giant vesicle and lipoparticle of different shape.We discuss the influence of particle size on the energy system.The free energy is smaller when the side length of the contact is larger.We also inferred the rotational behavior of anisotropic lipoparticle.Besides,we compared the free energy of nanoparticles of different shape,the energy of spherical particle is larger,and the energy of anisotropic particle is smaller.In Chapter 4,we summarize the simulation results,and also look forward to the next step in the direction of theoretical.