Preparation and mechanical characterization of artificial hollow tubes

In this paper, we present a novel route to prepare hollow tubes using the template assisted Layer-by-Layer technique. A readily available glass fibre template was coated with polyelectrolyte multilayers, followed by subsequent fibre dissolution. After the fibre dissolution we discovered stable hollow tubes or observed a pearling instability depending on the composition of the multilayer. Here we focus on hollow tubes: we precisely characterized the tubes with Fluorescence Microscopy, Confocal Laser Scanning Microscopy and AFM Topography Imaging. The tubes have an aspect ratio of around 10, with diameters from 5 μm up to 17 μm. The Layer-by-Layer technique allows us to control the tubes' wall thickness within a few nanometers; here the total wall thickness was 60 nm. Because the tubes can find a possible application in drug delivery, we tested the permeability of the multilayer membrane. The mechanical properties of the wall were investigated with AFM Force Spectroscopy and because continuum mechanical models apply to this system we derived a Young's modulus of the wall material.