Abstract
Organic biopolymer materials have been widely employed in various applications in recent years. Among all, deoxyribonucleic acid (DNA) biopolymer has several unique material properties, including the double helix structure, affinity with metal ions, non‐toxic and environmentally friendly characteristics. It has been a good template for metals and has been widely used not only in biology but also in optoelectronic devices, such as organic light‐emitting diodes (OLEDs) and organic memory devices. Metallic nanoparticles exhibit tunable surface plasmon resonances subject to different materials and dimensions. Such property has also drawn much attention in the applications of solar cell and surface enhanced Raman scattering. In this study, we combine the templating property of DNA and a photo‐triggered technique to fabricate DNA‐nanoparticle gratings with a period from millimeter to micrometer by light exposure. First part of the study, we employed the phototriggered method to synthesize metallic nanoparticles in a DNA biopolymer matrix.By varying the preparation conditions, we examined the photochemical synthesis processes by optical absorption spectra. The materials were further optimized and used for thin film deposition by drop casting and spin‐coating. In the second part of the study, we fabricated periodic grating structures on the DNA biopolymer film by light exposure. We define the exposure areas by the employment of a mask and an interferometer. The structures were characterized by various methods, including optical spectrometer, optical microscope, scanning electron microscope. The results show that DNA‐nanoparticle grating structures can be fabricated by light exposure with a period ranging from millimeters to tens of micrometers. Our demonstration reveals the potential of using light irradiation for the fabrication of DNA‐based grating structures, which holds promise for the applications of sensing and surface enhanced Raman scattering.