Investigation of morphology, micelle properties, drug encapsulation and release behavior of self-assembled PEG-PLA-PEG block copolymers: A coarse-grained molecular simulations study

Targeted drug delivery has become one of the key fields of personalized medicine. Developing candidate drug delivery agents requires a thorough understanding of the drug carrier materials by means of structure, drug encapsulation and release properties. To this aim, coarse-grained DPD simulations are employed to study the morphology, drug encapsulation and release of a particular amphiphilic block copolymer system. Extent of the drug encapsulation and release are observed to be mainly affected from copolymer concentration in the mixture. Mean aggregation number and average micelle volume are observed to increase as drug is encapsulated in the micelles. In addition, the shape of micelles is characterized as mainly spherical. It is observed that the drug release follows a pseudo-Fickian diffusion model and can be represented by the Korsmeyer-Peppas model. Furthermore, the diffusion rate of the drug molecules is observed to increase mainly in the release-phase. Our simulations can be viewed as a computational attempt to model the drug encapsulation and release by mimicking real experimental conditions, while yielding results on the structure and dynamics of the polymeric carrier. The results can be anticipated to find applications in understanding and controlling the parameters to design candidate drug delivery micelles at the molecular level.