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We investigate the conformation and dynamics of a semi-flexible polymer near an attractive plane or a cylindrical post using Langevin dynamics. We characterize the transition from the desorbed to absorbed state and quantify how absorption depends on the attraction interaction, polymer molecular weight, polymer flexibility, intra-polymer interaction, and micro-confinement. We find that the critical point of adsorption for ideal flexible polymers only weakly depends on confinement. However, the critical point of adsorption increases significantly for self-avoiding flexible polymers and under confinement, deviating from scaling theory predictions. These findings provide insights into DNA surface adsorption in nanoslits and nanochannels. [ABSTRACT FROM AUTHOR]

We investigated how very strong confinement, smaller than the polymer persistence length lp, affects the isotropic-nematic transition for semiflexible polymer solutions using GPU-accelerated Langevin dynamics. Walls facilitate polymer alignment, and under strong quasi-two-dimensional slitlike confinement, the I-N transition is found to be a continuous transition occurring via capillary nematization. We found that the I-N transition in the slit is a second-order transition, and the transition volume fraction ϕcr decreases with decrease of the slit height H. For H > lp, the critical exponent of the order parameter is found to be β ≈ 0.3-0.5. β sharply increases for H higher than a critical height, indicating the onset of a different wall-induced phase transition. Higher ϕcr are found for larger H, which is associated with increased monomer packing near the walls and correspond to the partial wetting transition predicted by self-consistent field theory. [ABSTRACT FROM AUTHOR]