POLYMER TRANSLOCATION INDUCED BY ADSORPTION

We study the translocation of a flexible polymer through a pore in a m embrane induced by its adsorption on the trans side of the membrane. W hen temperature T is higher than T-c, the adsorption-desorption transi tion temperature, the attractive interaction between polymer and membr ane plays little role in affecting polymer conformation, leading to tr anslocation time that scales as tau similar to L-3, where L is the pol ymer contour length. When T<T-c, however, the translocation time under goes a sharp crossover to tau similar to L-2 for sufficiently long pol ymers, following the second-order conformational (adsorption) transiti on. The translocation time is found to exhibit the crossover around T= T-c', which is lower than T-c for polymers shorter than a critical len gth (N < N-c). (C) 1998 American Institute of Physics.