Enabling direct laser writing of cellulose-based submicron architectures

Abstract

We report on the first and versatile cellulose-based photoresist, which can be applied in direct laser writing and allows the fabrication of structures with a resolution of less than 1 μm and a feature size of less than 500 nm via two-photon absorption. Therefore, cellulose diacetate is functionalised with methacrylic acid anhydride to introduce photo-crosslinkable side groups into the cellulose chain. The photoresist consists of the methacrylated cellulose diacetate and a photoinitiator both dissolved in acetone. The cellulose-based photoresist can be applied to generate two- and three-dimensional hierarchical structures and clears the way to the design and fabrication of biomimetic architectures solely made from biopolymers. A photo-crosslinkable cellulose-based resist, which can be applied in direct laser writing (DLW), was synthesised. It enables the generation of two- and three-dimensional hierarchical structures with a feature size of less than 500 nm via two-photon absorption. This new photoresist paves the way towards designing and fabricating biomimetic architectures solely made from biopolymers.