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Abstract We present a versatile platform for fabricating two‐photon excitable carbon dot‐based nanocomposite thin films by harnessing the structural versatility of polymer brushes in combination with electron‐beam lithography (EBL). This approach enables the precise spatial organization of carbon dots (CDs) at the nanoscale, facilitating dynamic modulation of their photoluminescent properties in response to environmental stimuli. Three model systems were examined, incorporating pH‐ and thermally responsive polymers, functionalized through covalent and dynamic covalent bonding strategies. By leveraging the spatial control afforded by nanostructured polymer brushes, we achieved precise tuning of optical properties while mitigating aggregation‐induced quenching, a longstanding challenge in solid‐state CD applications. In addition to the advances in controlling optical properties, this work highlights the potential of polymer brush systems to function as optically active, reprogrammable surfaces. The resulting nanoscale‐engineered materials exhibit highly responsive, reconfigurable photonic behavior, offering a scalable pathway for integrating advanced optical interfaces into microchip technologies, biosensing platforms, and multiplexed diagnostic systems. The fusion of polymer brushes, carbon dots, and advanced lithographic techniques marks a substantial advancement in the development of functional materials with nanoscale precision and stimuli‐responsive properties.
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This content will become publicly available on January 1, 2026
Gold Nanorod-Coated Hydrogel Brush Valves in Macroporous Silicon Membranes for NIR-Driven Localized Chemical Modulation
A two-dimensional array of microfluidic ports with remote-controlled valve actuation is of great interest for applications involving localized chemical stimulation. Herein, a macroporous silicon-based platform where each pore contains an independently controllable valve made from poly(N-isopropylacrylamide) (PNIPAM) brushes is proposed. These valves are coated with silica-encapsulated gold nanorods (GNRs) for NIR-actuated switching capability. The layer-by-layer (LBL) electrostatic deposition technique was used to attach the GNRs to the PNIPAM brushes. The deposition of GNRs was confirmed by dark-field optical microscopy, and the localized surface plasmon resonance (LSPR) of the deposited GNRs was analyzed using UV-Vis spectra. To evaluate the chemical release behaviors, fluorescein dye was employed as a model substance. The chemical release properties, like OFF-state diffusion through the valve, the ratio between ON-state and OFF-state chemical release, and the rapidness of chemical modulation of the valve, were investigated, varying the PNIPAM brush thickness. The results indicate that enhancing the thickness of the PNIPAM brush in our platform improves control over the chemical modulation properties. However, excessive increases in brush length may lead to entanglement, which negatively impacts the chemical modulation efficiency.
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- Award ID(s):
- 1952469
- PAR ID:
- 10566587
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Gels
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2310-2861
- Page Range / eLocation ID:
- 25
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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