Translocation of Micelles through a Nanochannel

Flow-driven translocation of micelles self-assembled from amphiphilic diblock copolymers through a nanochannel is studied by using hybrid lattice-Boltzmann molecular dynamics simulations. It is discovered that the structure of the translocating micelles depends on their initial sizes. Intact translocation occurs for small micelles, whereas fragmented translocation takes place for large micelles. The fragmented micelles reassemble to form an intact micelle after translocation. Coexistence of these two translocation modes is observed when the size of the initial micelle core is similar to that of the nanochannel. The critical translocation flow flux, at which the probability of translocation equals to 0.5, is found to increase rapidly with the aggregation number of the initial micelles in the intact translocation regime, whereas it remains approximately a constant in the fragmented translocation regime. The number of fragmented translocating micelles is found to be a linear function of the aggregation number. These findings provide an understanding of the dynamics of micelle translocation.