The optical properties and surface-enhanced Raman scattering (SERS) of plasmonic nanodome array (PNA) substrates in air and aqueous solution are investigated. PNA substrates are inexpensively and uniformly fabricated with a hot spot density of 6.25 × 10(6) mm(-2) using a large-area nanoreplica moulding technique on a flexible plastic substrate. Both experimental measurement and numerical simulation results show that PNAs exhibit a radiative localized surface plasmon resonance (LSPR) due to dipolar coupling between neighboring nanodomes and a non-radiative surface plasmon resonance (SPR) resulting from the periodic array structure. The high spatial localization of electromagnetic field within the ∼10 nm nanogap together with the spectral alignment between the LSPR and excited and scattered light results in a reliable and reproducible spatially averaged SERS enhancement factor (EF) of 8.51 × 10(7) for Au-coated PNAs. The SERS enhancement is sufficient for a wide variety of biological and chemical sensing applications, including detection of common metabolites at physiologically relevant concentrations.
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Analyst
January 2025
Department of Engineering and Architecture, University of Trieste, via A. Valerio 6, 34127 Trieste, Italy.
Ergothioneine (ERG) is a natural sulfur-containing amino acid found in many organisms, including humans. It accumulates at high concentrations in red blood cells and is distributed to various organs, including the brain. ERG has numerous health benefits and antioxidant capabilities, and it has been linked to various human physiological processes, such as anti-inflammatory, neuroprotective, and anti-aging effects.
View Article and Find Full Text PDFRSC Adv
January 2025
The Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University 3-14-1 Hiyoshi, Kohoku-ku Yokohama 223-8522 Japan +81-45-566-1580 +81-45-566-1839.
We prepared a cellulose nanofiber (CNF)-based porous membrane with three dimensional cellular structures. CNF was concentrated a surfactant-induced assembly by mixing CNF with a cationic surfactant, domiphen bromide (DB). Furthermore, they were accumulated by centrifugation to obtain a CNF-DB sol.
View Article and Find Full Text PDFAnal Chem
January 2025
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, PR China.
An entropy-driven catalysis (EDC) strategy is appealing for amplified bioimaging of microRNAs in living cells; yet, complex operation procedures, lacking of cell selectivity, and insufficient accuracy hamper its further applications. Here, we introduce an ingenious all-in-one entropy-driven DNA nanomachine (termed as AIO-EDN), which can be triggered by endogenous apurinic/apyrimidinic endonuclease 1 (APE1) to achieve tumor cell-selective dual-mode imaging of microRNA. Compared with the traditional EDC strategy, the integrated design of AIO-EDN achieves autocatalytic signal amplification without extra fuel strands.
View Article and Find Full Text PDFJ Phys Condens Matter
January 2025
Dep. Fisica, Universidade Federal de Minas Gerais, ICEX, Av. Antonio Carlos 6627, Belo Horizonte, MG, 31270-901, BRAZIL.
Nowadays, experimental research advances in condensed matter physics are deep-rooted in the development and manipulation of nanomaterials, making it essential to explore the fundamental properties of materials that are candidates for nanotechnology. In this work, we study the dependence of the molybdenum disulfide (MoS2) Raman modes on the sample temperature and on the excitation laser power. From the correlation between these two sets of measurements, we determine the planar thermal conductivity of MoSmonolayers, bilayers, trilayers, four layers, seven layers, and eight layers.
View Article and Find Full Text PDFAnal Methods
January 2025
Engineering Research Center of Intelligent Theranostics Technology and Instruments, Ministry of Education, School of Biomedical Engineering and Informatics, Nanjing Medical University, Nanjing, 211166, China.
The presented research introduces a new method to identify drug-resistant bacteria rapidly with high accuracy using artificial intelligence combined with Multi-angle Dynamic Light Scattering (MDLS) signals and Raman scattering signals. The main research focus is to distinguish methicillin-resistant (MRSA) and methicillin-sensitive (MSSA). First, a microfluidic platform was developed embedded with optical fibers to acquire the MDLS signals of bacteria and Raman scattering signals obtained by using a Raman spectrometer.
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