Desorption of a Flexible Polymer with Activity from a Homogeneous Attractive Surface

Abstract

The interfacial behavior of a flexible polymer with activity, which is named active Brownian polymer (ABPO), is studied by Langevin dynamics simulations. On the dependence of the adsorption strength and activity characterized by the Pećlet number (Pe), the polymer displays two typical states on the surface: adsorption and desorption states. We find that the diffusion behavior of ABPO that is parallel to the surface yields the "active Rouse model" and the activity causes the adsorption− desorption transition at a certain adsorption strength. Particular attention is given to how the desorption time, τ des , changes with the activity. At intermediate activity, τ des displays an exponential decay with the inverse of the effective temperature, T eff ∝1 + Pe 2 /18, which is reminiscent of the mechanism of thermal activation. At higher activity, due to easily overcoming the attractive energy barrier, τ des ∝Pe −1 is found. At lower activity, a power-law dependence of τ des on the diffusion coefficient perpendicular to the surface (D ⊥ ) is observed (τ des ∼D ⊥ −1.28 ). Further, we observed a non-monotonic dependence of desorption time on the rotation diffusion coefficient D R of the monomer and found that τ des exists on a scaling relation with the chain length N, τ des ∼ N ϕ , and the scaling exponent ϕ decreases with the increase of activity. Our results highlight that the activity can be used to regulate the polymer adsorption and desorption behavior.

Adsorption of active polymers on attractive nanoparticles

“…27 The adsorption/desorption of active polymers fully composed of self-propelled particles on/ from attractive surfaces was strongly affected by the magnitude of the active force on self-propelled particles. 28,29 Biopolymers are often in crowded environments such as living cells, which are filled with various proteins, nucleic acids, chromatins, actins, lipid membranes, and more. 30 The motion of biopolymers is significantly affected by the surrounding particles.…”

“…27 The adsorption/desorption of active polymers fully composed of self-propelled particles on/from attractive surfaces was strongly affected by the magnitude of the active force on self-propelled particles. 28,29…”

Langevin dynamics simulations for the critical adsorption of end-grafted active polymers

“…24 Meanwhile, the adsorption of active polymers with random or tangential activity was influenced by the active force. 25,26 For a tethered semiflexible active polymer chain under tangential active force, the adsorbed polymer forms a rotating quasihelical with a rotational speed proportional to the active force. 27 Some biological systems, such as spermatozoa, bacilli, and spirochetes, have elongated organisms and can move with the help of active parties of their bodies.…”

“…24 Meanwhile, the adsorption of active polymers with random or tangential activity was influenced by the active force. 25,26 For a tethered semiflexible active polymer chain under tangential active force, the adsorbed polymer forms a rotating quasihelical with a rotational speed proportional to the active force. 27…”