Abstract
This work uses dissipative particle dynamic simulation to study on morphology of drug carrier MPEG-b-(PLA-co-PAE) with different block ratio, copolymer concentration and drug concentration. In different condition, drug loading efficiency and drug distribution in drug carrier are investigated. Finally,in weakly acidic environment, drug carrier morphology and drug releasing situation will also be discussed.In this work, we use amphiphilic pH-sensitive copolymer as drug carrier, composed of hydrophobic poly(β-amino ester)(PAE) and hydrophilic poly(ethylene glycol)(PEG). Because of its tertiary amine, PAE has a weak basic character and can be protonated at low pH. Therefore, PAE becoming hydrophilic causes the aggregation structure broken and drug releasing. Poly(β-amino ester)(PAE) is non-toxic and biodegradable, poly(ethylene glycol)(PEG) is biocompatible, and poly(lactide)(PLA) is biodegradable and bioabsorbable, thus PEG(-PAE)4 copolymer is promising candidate for drug delivery.The results indicate that drug loading efficiency and drug loading capability will increase while ratio of PEG block is increasing. In weakly acidic environment, the drug carrier size will become larger. And the larger ratio of PAE block, the larger size the drug carrier will become. It’s also represent faster drug releasing rate.