Reversible Shaping of Microwells by Polarized Light Irradiation

Abstract

In the last years, stimuli-responsive polymeric materials have attracted great interest, due to their low cost and ease of structuration over large areas combined with the possibility to actively manipulate their properties. In this work, we propose a polymeric pattern of soft-imprinted microwells containing azobenzene molecules. The shape of individual elements of the pattern can be controlled after fabrication by irradiation with properly polarized light. By taking advantage of the light responsivity of the azobenzene compound, we demonstrate the possibility to reversibly modulate a contraction-expansion of wells from an initial round shape to very narrow slits. We also show that the initial shape of the microconcavities can be restored by flipping the polarization by 90∘ . The possibility to reversibly control the final shape of individual elements of structured surfaces offers the opportunity to engineer surface properties dynamically, thus opening new perspectives for several applications.

Polarization Dependent Photoinduced Supramolecular Chirality in High-Performance Azo Materials

“…Furthermore, the “stretched layer effect” should be erasable by rotating the sample at 90 and repeating irradiation with exactly the same characteristics of incident beam (cf. [ 9 , 33 , 34 ]). A good sign for the “stretched layer effect” are experiments on photo-induced wrinkling.…”

Dynamic Manipulation of Cell Membrane Curvature by Light-Driven Reshaping of Azopolymer

“…On the other hand, curvatures on the cell membrane appear and disappear dynamically in response to complex intracellular and extracellular cues. Smart materials with the ability to change their 3D shapes upon light stimulation would afford a new approach to manipulate membrane curvatures on-demand. − …”

Plasmonic Photomobile Polymer Films

“…Among the few examples where an ordered structure, i.e., a 2D crystal made by micropillars/ microwells, is modified by the action of light, we remind of the one recently reported by Pirani et al [17,18]. In addition in this case, the photo-isomerization of azobenzene moieties is exploited.…”