Quantitative analysis of end-to-end distance of single polymer chain in ultra-thin film by super-resolution fluorescence imaging

The end-to-end distance, R, of individual poly(methyl methacrylate) (PMMA) chains was evaluated for the individual chains by the super-resolution fluorescence microscopy, which determines the positions of the dye molecules introduced at both ends of a PMMA chain. The observed value of R was in good agreement with that reported by SANS experiments, and the distribution function was well fitted to the theoretical model of the random walk chain. The accuracy to determine the root of mean-square end-to-end distance is on the order of 1 nm. The distribution function of R obtained for the single PMMA chain in an ultra-thin film was almost the same as that in a bulk state. This indicates that the chain dimension in the ultra-thin was not significantly altered in the direction normal to the spatial confinement. (C) 2012 Elsevier B.V. All rights reserved.