Nanoimprinted Collagen Plasmonic Sensors

Biopolymers are interesting technological platforms for green and eco‐friendly devices while enabling the desirable biocompatibility. Herein, micro‐ and nanostructures have been fabricated on the biopolymer collagen type I using thermo‐nanoimprinting lithography (T‐NIL) under relatively low temperature and applied pressure. The collagen samples are prepared by spin coating directly on substrates or as self‐standing membranes by casting from cosmetic‐grade ovine collagen acidic solutions. After NIL parameter optimization, complex microstructures and nanostructures can be realized at temperatures as low as 125 °C under an applied pressure of 50 bar for 300 s. The nanopatterns and eventual collagen macrostructure changes are completely characterized by optical microscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermal analysis, and spectroscopy techniques. The broad utility of such nanopatterns as Bragg gratings and plasmonic sensors is discussed.