Selenium-decorated biocompatible honeycomb films with redox-switchable surface for controlling cell adhesion/detachment.

ABSTRACT

HYPOTHESIS: Selenium (Se)-containing compound is sensitive to redox stimulation, showing hydrophobic-hydrophilic reversible transition. Introduction of such compound into honeycomb film could confer on it redox-switchable surface wettability, which is expected to control cell adhesion/detachment behavior. EXPERIMENTS Didodecyl selenide was designed and mixed with polystyrene to prepare honeycomb films using "breath figure" method. The film microstructures were characterized by scanning electron microscope and atomic force microscopy, and the arrangement of Se atoms in honeycomb film was determined by X-ray photoelectron spectroscopy and energy dispersive spectrometry. The variation of film wettability upon the alternating stimulation of H2O2 and Vc was examined. Then the cell adhesion, proliferation, and controlled detachment on honeycomb films were conducted. FINDINGS: The introduction of didodecyl selenide helps to form ordered honeycomb film, and Se atoms were found to located on the bottom, pore walls, and top surface of the film. The presence of didodecyl selenide not only greatly improves film biocompatibility by enhancing cell thioredoxin reductase activity, but also imparts the film with H2O2-/vitamin C-regulated tunable wettability that controls cell adhesion and detachment. H2O2 treatment produces a hydrophilic surface for cell adhesion and proliferation, whereas the addition of vitamin C generates hydrophobic surfaces and allows cells to detach while remaining alive with high activity.