Simulation study on the translocation and separation of copolymers

The translocation of copolymers through a channel is studied by using Monte Carlo simulation. A copolymer (AnCn)m consists of monomer A and monomer C with different monomer–channel interactions, εA and εC, respectively. Under weak driving force and weak attraction between monomer C and the channel, the copolymer will be trapped at the exit of the channel at εA << 0 and the leaving time is highly dependent on the copolymerʹs structure and on the interaction εA. As a result, the translocation time of the copolymer is highly dependent on the copolymerʹs structure at εA << 0. The separation of copolymers by using a periodic devise with alternating large reservoirs and small channels is also simulated. Results show that different copolymers, with different sequences but of the same chain length, can be separated with properly chosen interactions.