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Background:The excellent physicochemical properties of graphene-based materials, including graphene oxide (GO) and reduced GO (rGO), offer significant technological potential as multifunctional nanomaterials in biomedical fields. Lutein is a type of carotenoid that forms human macular pigments in the retina, where it inhibits harmful blue light and contributes to the strengthening of the antioxidant defense of retinal pigment epithelium cells. Methods: Synthesis of the Lutein-rGO (Lu-rGO) complex was carried out for the optimized concentration. Then characterization of material was analyzed through ultraviolet-visible spectrophotometer (UV-Vis spectra), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM). Antioxidant activity of Lu-rGO complex was measured by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2.2-diphenyl-1-picrylhydrazyl (DPPH), glutathione (GSH) oxidation assay. Then, oxidative stress induction by blue light and analyzed intracellular reactive oxygen species (ROS). Results and Conclusion:Based on the FT-IR measurement, the reduction efficiency defined by area was found to be 87.3%, the I D /I G ratio of 0.98 demonstrated by the Lu-rGO complex in the Raman spectrum was slightly higher than that of the original GO. The exhibited significant decrease in the peak intensities of the oxygen functional groups of the XPS spectra of the Lu-rGO complex was observed compared with the GO. In the TEM image for the Lu-rGO complex, folded and wrinkled nanostructures over the lutein-covered rGO surface were evidenced by tight molecular binding. The Lu-rGO complex provided superior DPPH and ABTS radical scavenging activity than GO and lutein alone, and the oxidation of GSH was suppressed. It was confirmed that the content of intracellular ROS and lysosomes, increased by blue light, was reduced after treatment with the Lu-rGO complex on ARPE-19 cells. In summary, graphene-based nanocarriers could function as preventative antioxidants during photochemical ROS generation based on the mechanism of antioxidant action.

Rotating cylindrical stamp‐based nanoimprint technique has many advantages, including the continuous fabrication of intriguing micro/nanostructures and rapid pattern transfer on a large scale. Despite these advantages, the previous nanoimprint lithography has rarely been used for producing sophisticated nanoscale patterns on a non‐planar substrate that has many extended applications. Here, the simple integration of nanoimprinting process with a help of a transparent stamp wrapped on the cylindrical roll and UV optical source in the core to enable high‐throughput pattern transfer, particularly on a fabric substrate is demonstrated. Moreover, as a functional resin material, this innovative strategy involves a synergistic approach on the synthesis of molecularly imprinted polymer, which are spatially organized free‐standing perforated nanostructures such as nano/microscale lines, posts, and holes patterns on various woven or nonwoven blank substrates. The proposed materials can serve as a self‐encoded filtration medium for selective separation of formaldehyde molecules. It is envisioned that the combinatorial fabrication process and attractive material paves the way for designing next‐generation separation systems in use to capture industrial or household toxic substances.

Patterning of surfaces with a simple strategy provides insights into the functional interfaces by suitable modification of the surface by novel techniques. Especially, highly ordered structural topographies and chemical features from the wide range of interfaces have been considered as important characteristics to understand the complex relationship between the surface chemistries and biological systems. Here, we report a simple fabrication method to create patterned surfaces over large areas using evaporative self-assembly that is designed to produce a sacrificial template and lithographic etch masks of polymeric stripe patterns, ranging from micrometer to nanoscale. By facilitating a roll-on-plate geometry, the periodically patterned surface structures formed by repetitive slip-stick motions were thoroughly examined to be used for the deposition of the Au nanoparticles decorated graphene oxide (i.e., AuNPs, ~21 nm) and the formation of conductive graphene channels. The fluorescently labeled thiol-modified DNA was applied on the patterned arrays of graphene oxide (GO)/AuNPs, and biotin-streptavidin sensitive devices built with graphene-based transistors (GFETs, effective mobility of ~320 cm2 V−1 s−1) were demonstrated as examples of the platform for the next-generation biosensors with the high sensing response up to ~1 nM of target analyte (i.e., streptavidin). Our strategy suggests that the stripe patterned arrays of polymer films as sacrificial templates can be a simple route to creating highly sensitive biointerfaces and highlighting the development of new chemically patterned surfaces composed of graphene-based nanomaterials.

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