Direct Laser Writing of Photostable Fluorescent Silver Nanoclusters in Polymer Films

Abstract

11Metal nanoclusters consist of a few to few hundreds of atoms, and exhibit attractive molecular 12 properties such as ultrasmall size, discrete energy levels and strong fluorescence. Although 13 patterning of these clusters down to the microscale or nanoscale could lead to 14 applications such as high-density data storage, it has been reported only for inorganic 15matrices. Here we demonstrate the first submicron-scale mask-free patterning of fluorescent 16 silver nanoclusters in an organic matrix. The nanoclusters were produced by direct 17 laser writing in poly(methacrylic acid) thin films, and exhibit a broadband emission at visible 18 wavelengths with photostability that is superior to Rhodamine 6G dye. This fabrication 19 method could open new opportunities for applications in nanophotonics like imaging, 20 labeling, and metal ion sensing. We foresee that this method can be further applied to prepare 21 other metal nanoclusters embedded in compositionally different polymer matrices. 22 KEYWORDS 24Optical lithography, metal nanoclusters, photoluminescence, photobleaching, photostability, 25 polymer 26

Multivalent Glycosylation of Fluorescent Gold Nanoclusters Promotes Increased Human Dendritic Cell Targeting via Multiple Endocytic Pathways

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High Numerical Aperture Hexagonal Stacked Ring-Based Bidirectional Flexible Polymer Microlens Array

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Nucleic‐Acid Structures as Intracellular Probes for Live Cells

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“…Representing a new class of fluorophores, silver nanoclusters are of interest due to their good photostability and low cytotoxicity. [129,[214][215][216] Strategies employing silver nanoclusters take advantage of the high sensitivity of their fluorescence to ONT surroundings. Yeh et al have reported silver nanoclusters that transition from a dark state to a red emitting state when in close proximity to guanine bases.…”