Chain deformation in translocation phenomena

• DOI: 10.1039/c2sm27416g
• Publication Date: 2013-01-24T14:55:56Z
• Authors: Farnoush Farahpour; Azadeh Maleknejad; Fathollah Varnik; Mohammad Reza Ejt...
• Keywords: 0303 health sciences; 03 medical and health sciences; Quantitative Biology - Biomolecules; FOS: Biological sciences; 0103 physical sciences; Soft Condensed Matter (cond-mat.soft); FOS: Physical sciences; Biomolecules (q-bio.BM); Condensed Matter - Soft Condensed Matter; 01 natural sciences

Deformation of single stranded DNA in translocation process before reaching the pore is investigated. By solving the Laplace equation in a suitable coordinate system and with appropriate boundary conditions, an approximate solution for the electric field inside and outside of a narrow pore is obtained. With an analysis based on "electrohydrodynamic equivalence" we determine the possibility of extension of a charged polymer due to the presence of an electric field gradient in the vicinity of the pore entrance. With a multi-scale hybrid simulation (LB-MD), it is shown that an effective deformation before reaching the pore occurs which facilitates the process of finding the entrance for the end monomers. We also highlight the role of long range hydrodynamic interactions via comparison of the LB-MD results with those obtained using a Langevin thermostat instead of the LB solver.<br/>to appear in softmatter<br/>