The sensitivities of resonant wavelengths of photonic crystal (PhC) membrane nanocavities with embedded InAs quantum dots to the ambient refractive index are reported for use in (bio) chemical sensing. The resonances for the different modes of several point-defect type cavities are obtained by photoluminescence measurements. Systematic trends of the variation of sensitivity with increase of the overlap of the modes with the PhC holes are observed for varying cavity type as well as for a given mode within a cavity type. A maximum sensitivity of approximately 300 nm/RIU (refractive index unit) is observed, corresponding to approximately 25% mode overlap with the holes and complete infiltration with the aqueous solution.
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http://dx.doi.org/10.1364/OE.18.004049 | DOI Listing |
Sci Rep
December 2024
Department of Electronics, Carleton University, Ottawa, ON, K1S 5B6, Canada.
In this paper, we propose a novel structure of anisotropic graphene-based hyperbolic metamaterial (AGHMM) sandwiched as a defect between two one-dimensional photonic crystals (PCs) in the terahertz (THz) region. The proposed structure is numerically simulated and analyzed using the transfer matrix method, effective medium theory and three-dimensional finite-difference time-domain. The defect layer of AGHMM consists of graphene sheets separated by subwavelength dielectric spacers.
View Article and Find Full Text PDFTalanta
December 2024
Institute of Biomedical Precision Testing and Instrumentation, College of Artificial Intelligence, Taiyuan University of Technology, Taiyuan, Shanxi, 030600, PR China.
Developing a fluorescence sensing platform for point-of-care detection of low abundance biomarkers is highly valuable for early diagnosis of disease. Herein, a biomimetic fluorescence-enhanced platform based on photonic crystals and DNAzyme walker was constructed and further applied to visualize and quantify the miRNA-21 in biological samples. The DNAzyme walker was orthogonally activated by the target miRNA-21, which enabled the unlocking of the DNAzyme walker strand and the subsequently repeated substrate cleavage, thus generating enhanced fluorescence signals.
View Article and Find Full Text PDFFood Chem
December 2024
Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, 300070 Tianjin, People's Republic of China; Tianjin Key Laboratory of Environment, Nutrition and Public Health, Center for International Collaborative Research on Environment, Nutrition and Public Health, Tianjin Medical University, Tianjin, People's Republic of China. Electronic address:
A novel biomimetic molecular imprinted polymer chip with fluorescence (FL) and structural (STR) states, inspired by color patterns of chameleon skin, is fabricated for detecting diethylstilbestrol (DES). The chip features a regularly structured, non-closed-packed (NCP) colloidal photonic crystal (CPC) lattice made monodisperse MIP spheres containing fluorescence poly ionic liquid (FPIL) pigments. The FL color originates from FPIL pigments and is further enhanced by the Purcell effect, while the STR color results from the periodic arrangement of the NCP CPC structure.
View Article and Find Full Text PDFNanomicro Lett
December 2024
Department of Chemistry and Laboratory of Advanced Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers, Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM), College of Chemistry and Materials, Fudan University, Shanghai, People's Republic of China.
Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers, because of their potential harm to the respiratory system, nervous system, skin, and eyes. However, research on chloroform vapor sensing is still in its early stages, primarily due to the lack of specific recognition motif. Here we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor (HMSS@CDs-PCs) for enhanced chloroform sensing.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Composites and Nanocomposites Center, Moroccan Foundation for Advanced Science, Innovation and Research, Rabat Design Center, Rue Mohamed El Jazouli, Madinat El Irfane, Rabat 10100, Morocco; Mohammed VI Polytechnic University, Lot 660 Hay Moulay Rachid, 43150 Ben Guerir, Morocco. Electronic address:
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