277 results match your criteria: "Singapore 117543 [2] Institute of Materials Research and Engineering[Affiliation]"

A rapid total bacterial count method using gold nanoparticles conjugated with an aptamer for water quality assessment.

Nanoscale

October 2023

Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore 138634, Republic of Singapore.

Article Synopsis
  • Total bacterial count is crucial for assessing microbial safety in areas like drinking water, but traditional methods take over 24 hours and need a laboratory setting.
  • A new method called "Filter-and-Stain" was developed using gold nanoparticles with affinity ligands to stain bacteria quickly, achieving results in just 20 minutes and detecting as few as 100 CFU/mL.
  • This innovative approach has been successfully tested on environmental water samples, suggesting it could enhance rapid on-site testing for bacterial contamination.
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A copper-iodide cluster microcube-based X-ray scintillator.

Light Sci Appl

September 2023

Joint School of the National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, 350207, Fuzhou, China.

Newly developed copper-iodide cluster microcubes offer a solution to the issues commonly faced by powder scintillation screens. These problems include inadequate scintillation performance and significant light scattering, resulting in poor image quality. With the advent of monodisperse copper-iodide cluster microparticle scintillators, efficient and long-term stable scintillation is achieved, while ensuring biocompatibility.

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Interlayer donor-acceptor pair excitons in MoSe/WSe moiré heterobilayer.

Nat Commun

September 2023

Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.

Localized interlayer excitons (LIXs) in two-dimensional moiré superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks.

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Precisely controlled impurity doping is of fundamental significance in modern semiconductor technologies. Desired physical properties are often achieved at impurity concentrations well below parts per million level. For emergent two-dimensional semiconductors, development of reliable doping strategies is hindered by the inherent difficulty in identifying and quantifying impurities in such a dilute limit where the absolute number of atoms to be detected is insufficient for common analytical techniques.

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Emergent quantum phenomena in two-dimensional van der Waal (vdW) magnets are largely governed by the interplay between exchange and Coulomb interactions. The ability to precisely tune the Coulomb interaction enables the control of spin-correlated flat-band states, band gap, and unconventional magnetism in such strongly correlated materials. Here, we demonstrate a gate-tunable renormalization of spin-correlated flat-band states and bandgap in magnetic chromium tribromide (CrBr) monolayers grown on graphene.

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Two-dimensional indium(III) selenide (InSe) is characterized by rich polymorphism and offers the prospect of overcoming thickness-related depolarization effects in conventional ferroelectrics. α-InSe has attracted attention as a ferroelectric semiconductor that can retain ferroelectricity at the monolayer level; thus, it can be potentially deployed in high density memory switching modes that bypasses the traditional von Neumann architecture in device design. However, studies involving α-InSe are often hindered by difficulties in phase identification owing to mixing with β-InSe.

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Vacancies pose a major challenge in the production of high-quality crystals, particularly at the nanoscale. To address this problem, we report a convenient strategy that involves volumetric lattice reconstruction and dynamic metal complex docking to produce ultrasmall (10 nm) and bright core-shell upconversion nanoparticles (UCNPs). This strategy involves the formation of lanthanide ion-oleic acid complexes during postannealing in solution, which effectively removes vacancies in nanocrystals.

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Battery-free and AI-enabled multiplexed sensor patches for wound monitoring.

Sci Adv

June 2023

Institute of Materials Research and Engineering (IMRE), Agency for Science Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore 138634, Republic of Singapore.

Article Synopsis
  • Wound healing involves complex processes and currently faces challenges in accurately measuring inflammation and infection levels.
  • The PETAL sensor is a battery-free, paper-based device that uses deep learning to analyze various wound characteristics through colorimetric sensors for factors like temperature and pH.
  • This sensor has shown a high accuracy (up to 97%) in determining the healing status of wounds in rats, enabling real-time monitoring and early detection of complications for better wound care management.
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Optical transparency is rare in terrestrial organisms, and often originates through loss of pigmentation and reduction in scattering. The coloured wings of some butterflies and moths have repeatedly evolved transparency, offering examples of how they function optically and biologically. Because pigments are primarily localized in the scales that cover a colourless wing membrane, transparency has often evolved through the complete loss of scales or radical modification of their shape.

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Spin Defects in hBN assisted by Metallic Nanotrenches for Quantum Sensing.

Nano Lett

June 2023

Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.

The omnipresence of hexagonal boron nitride (hBN) in devices embedding two-dimensional materials has prompted it as the most sought after platform to implement quantum sensing due to its testing while operating capability. The negatively charged boron vacancy () in hBN plays a prominent role, as it can be easily generated while its spin population can be initialized and read out by optical means at room-temperature. But the lower quantum yield hinders its widespread use as an integrated quantum sensor.

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Quantum sensing of radio-frequency signal with NV centers in SiC.

Sci Adv

May 2023

Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.

Silicon carbide is an emerging platform for quantum technologies that provides wafer scale and low-cost industrial fabrication. The material also hosts high-quality defects with long coherence times that can be used for quantum computation and sensing applications. Using an ensemble of nitrogen-vacancy centers and an XY8-2 correlation spectroscopy approach, we demonstrate a room-temperature quantum sensing of an artificial AC field centered at ~900 kHz with a spectral resolution of 10 kHz.

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Gate-Tunable Bound Exciton Manifolds in Monolayer MoSe.

Nano Lett

May 2023

Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.

Two-dimensional (2D) semiconductors with point defects are predicted to host a variety of bound exciton complexes analogous to trions and biexcitons due to strong many-body effects. However, despite the common observation of defect-mediated subgap emission, the existence of such complexes remains elusive. Here, we report the observation of bound exciton (BX) complex manifolds in monolayer MoSe with intentionally created monoselenium vacancies (V) using proton beam irradiation.

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Well-ordered spin arrays are desirable for next-generation molecule-based magnetic devices, yet their synthetic method remains a challenging task. Herein, we demonstrate the realization of two-dimensional supramolecular spin arrays on surfaces via halogen-bonding molecular self-assembly. A bromine-terminated perchlorotriphenylmethyl radical with net carbon spin was synthesized and deposited on Au(111) to achieve two-dimensional supramolecular spin arrays.

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Perovskite emitters are promising materials as next-generation optical sources due to their low fabrication cost and high quantum yield. In particular, the superradiant emission from a few coherently coupled perovskite emitters can be used to produce a bright entangled photon source. Here, we report the observation of superradiance from mesoscopic (<55) CsPbBr perovskite emitters, which have a much smaller ensemble size than the previously reported results (>10 emitters).

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Plasmonic nanostructures have shown immense potential in photocatalysis because of their distinct photochemical properties associated with tunable photoresponses and strong light-matter interactions. The introduction of highly active sites is essential to fully exploit the potential of plasmonic nanostructures in photocatalysis, considering the inferior intrinsic activities of typical plasmonic metals. This review focuses on active site-engineered plasmonic nanostructures with enhanced photocatalytic performance, wherein the active sites are classified into four types (i.

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The ideal single-photon source displaying high brightness and purity, emission on-demand, mature integration, practical communication wavelength (i.e., in the telecom range), and operating at room temperature does not exist yet.

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Surface Engineering of Lanthanide Nanoparticles for Oncotherapy.

Acc Chem Res

February 2023

Department of Chemistry, National University of Singapore, Singapore 117543, Singapore.

Surface-modified lanthanide nanoparticles have been widely developed as an emerging class of therapeutics for cancer treatment because they exhibit several unique properties. First, lanthanide nanoparticles exhibit a variety of diagnostic capabilities suitable for various image-guided therapies. Second, a large number of therapeutic molecules can be accommodated on the surface of lanthanide nanoparticles, which can simultaneously achieve combined cancer therapy.

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Intensive research in electrochemical CO reduction reaction has resulted in the discovery of numerous high-performance catalysts selective to multi-carbon products, with most of these catalysts still being purely transition metal based. Herein, we present high and stable multi-carbon products selectivity of up to 76.6% across a wide potential range of 1 V on histidine-functionalised Cu.

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Aggregation-Induced Emission-Active Nanostructures: Beyond Biomedical Applications.

ACS Nano

February 2023

Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833.

The discovery of aggregation-induced emission (AIE) phenomenon in 2001 has had a significant impact on materials development across different research disciplines. AIE-active materials have been widely exploited for various applications in optoelectronics, sensing, biomedical, and stimuli-responsive systems, etc. This is made possible by integrating AIE features with other fields of science and engineering, such as nanoscience and nanotechnology.

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Antibody conjugated Au/Ir@Cu/Zn-MOF probe for bacterial lateral flow immunoassay and precise synergistic antibacterial treatment.

Biosens Bioelectron

March 2023

Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, 510006, People's Republic of China. Electronic address:

Staphylococcus aureus is one of the most prevalent threats to public health. Rapid detection with high sensitivity and targeted killing is crucial to curb its spread. Herein, a metal-bearing nanocomposite, consisting of a bimetallic nanoparticle and a metal-organic framework (Au/Ir@Cu/Zn-MOF) was constructed.

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Inorganic halide perovskite quantum dots have risen in recent years as efficient active materials in numerous optoelectronic applications ranging from solar cells to light-emitting diodes and lasers, and have lately been tested as quantum emitters. Perovskite quantum dots are often coupled to photonic structures either to enhance their emission properties, by accelerating their emission rate thanks to the Purcell effect, or to increase light extraction. From a theoretical point of view, the first effect is often considered at the single-dipole level while the latter is often treated at the mesoscopic level, except possibly for quantum emitters.

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Valorization of Spent coffee Grounds: A sustainable resource for Bio-based phase change materials for thermal energy storage.

Waste Manag

February 2023

Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, Innovis, #08-03 138634, Singapore; School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link 637371, Singapore. Electronic address:

Spent coffee grounds (SCGs) are waste residues arising from the process of coffee brewing and are usually sent to landfills, causing environmental concerns. SCGs contain a considerable amount of fatty acids and is therefore a promising green alternative bio-based phase change material (PCMs) compared to conventional organic and inorganic PCMs. In this study, the extraction of coffee oil from SCGs was conducted using three different organic solvents-ethanol, acetone, and hexane.

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Background: Food processing plays an important role in the modern industry because food quality and security directly affect human health, life safety, and social and economic development. Accurate, efficient, and sensitive detection technology is the basis for ensuring food quality and security. Optosensor-based technology with the advantage of fast and visual real-time detection can be used to detect pesticides, metal ions, antibiotics, and nutrients in food.

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Metal-free 2D phosphorus-based materials are emerging catalysts for ammonia (NH ) production through a sustainable electrochemical nitrogen reduction reaction route under ambient conditions. However, their efficiency and stability remain challenging due to the surface oxidization. Herein, a stable phosphorus-based electrocatalyst, silicon phosphide (SiP), is explored.

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