Abstract
Amphiphilic diblock copolymer self-assemble into micelle and vesicle which have been extensively studied as carriers. Carriers have ability to increase drug solubility, exhibit controlled release and protect drug from inactivation. Until now, dissipative particle dynamics (DPD) used to simulate drug delivery systems has been fully developed. This work mainly study linear block copolymers and star-shaped block copolymers with different arms and compare their performance to each other. Because the viscosity can affect drug loading efficiency, this work will investigate under shear flow system and analyze their viscosity. In this work, biodegradable polymers based on star-shaped (PEO-PLA)n will be material of drug carrier. Poly(D-L lactide acid) (PLA) is biodegradable polymer which is one mechanism of drug releasing. Poly(ethylene oxide (PEO) exhibit a high solubility, non-toxic and larger hydrodynamic radius, thus contributed to renal excretion and other characteristics.The systems of simulation are in dilute solution in this work. The results indicate that linear block copolymers will all self-assemble into spherical micelles. And star-shaped block copolymers will self-assemble into multicore micelle, donut micelle and net structure by changing ratio of the PLA block. When the star-shaped block copolymers have more arms, viscosity will be lower and drug loading efficiency will be better. Larger ratio of the PLA block, there is a better drug loading efficiency.