Anatoly Kolomeisky, Rice University, and his team describe an improved theoretical model for the movement of long chain polymers through nanopores. This kind of movement is a key part of many biological processes.

The new model addresses both cylindrical pores and tapering pores that simulate the α–hemolysin membrane channel. In modeling a tapering pore, the scientists confirmed that translocation occurs faster when the polymer enters the wide side of the pore.

Contrary to current models, it takes into account the motion of the polymer inside the pore. By improving the boundary conditions for polymer movement inside the pore, the team demonstrated a significant increase in total time in the pore compared to earlier models.

Possible technological applications include advances in DNA sequencing and the development of biosensors using membranes.

• Polymer translocation through pores with complex geometries
  Aruna Mohan, Anatoly B. Kolomeisky, Matteo Pasquali
  J. Chem. Phys. 2010, 133.
  DOI: 10.1063/1.3458821