Engineered protein-based functional nanopatterned materials for bio-optical devices

Abstract

A simple approach for the fabrication of functional nanopatterned protein materials using protein engineering and soft-nanolithography and its implementation in optical devices based on distributed feedback (DFB) laser phenomena.

Multifunctional Structured Platforms: From Patterning of Polymer-Based Films to Their Subsequent Filling with Various Nanomaterials

“…Generally, in order to transfer a pattern from the mold to polymeric films deposited on flexible [ 107 ], solid [ 108 ], or textile [ 3 ] substrates, molds are mechanically pressed against a polymer melt [ 109 ] or films while heating the latter to melting temperatures [ 110 , 111 ] ( Figure 5 a). For efficiency reasons, it is also possible to press the molds against films soaked with non-solvents to form surface “gels” [ 112 ], or against as drop-cast solutions [ 113 ] or even to poor solutions of interest directly on the mold [ 114 ] and heat afterwards.…”

Patterning of protein‐based materials

“…Traditional radical‐based crosslinkers, for instance methylene blue or ruthenium 2+ ‐based complexes, are often cell toxic and, therefore, less suitable for biomedical applications. [ 38 ] Glutaraldehyde, known to covalently crosslink lysine residues, [ 39 ] is also cell toxic. As an alternative, naturally occurring riboflavin, also known as vitamin B2, could act as a visible light‐addressable initiator in photo‐crosslinking processes, thus reducing potential damage of the protein integrity during fabrication.…”

Hydrogel‐Based Diffractive Optical Elements (hDOEs) Using Rapid Digital Photopatterning

“…This has led to the development of hydrogels with customizable properties such as the abilities to change shapes, resist mechanical forces, release target enzymes, and exhibit electrical, magnetic as well as optical properties. [ 7–14 ]…”

“…At present, hDOEs such as diffraction grating, holographic components, and Fresnel zone plates (FZP) are fabricated using indirect and direct methods. [ 7,22,26,29–31 ] Indirect methods, such as mask‐based photolithography, inverse opals, soft lithography, and nanoimprinting, require use of expensive physical masks, and time‐consuming iterative optimization to fabricate hDOEs. On the other hand, direct methods such as electron beam lithography, direct laser writing, and multibeam interference lithography do not require physical mask to fabricate high‐resolution hDOEs, however challenges with scalability and long processing/fabrication times remain.…”

“…This has led to the development of hydrogels with customizable properties such as the abilities to change shapes, resist mechanical forces, release target enzymes, and exhibit electrical, magnetic as well as optical properties. [7][8][9][10][11][12][13][14] designs, and these digital patterns were uploaded onto a digital micromirror device (DMD) to generate virtual masks (instead of conventional physical masks) to enable rapid printing of hDOEs. To highlight the broad applicability of this method, a range of diffractive devices such as 1D/2D diffraction gratings, Dammann grating, FZP lens, fork-shaped grating and computer-generated hologram (CGH) of arbitrary pattern were designed, printed and their optical performance were compared to DOEs made using conventional materials.…”