93 research outputs found
Superparamagnetic nanoarchitectures for disease-specific biomarker detection
© 2019 The Royal Society of Chemistry. The detection of clinically relevant disease-specific biomolecules, including nucleic acids, circulating tumor cells, proteins, antibodies, and extracellular vesicles, has been indispensable to understand their functions in disease diagnosis and prognosis. Therefore, a biosensor for the robust, ultrasensitive, and selective detection of these low-Abundant biomolecules in body fluids (blood, urine, and saliva) is emerging in current clinical research. In recent years, nanomaterials, especially superparamagnetic nanomaterials, have played essential roles in biosensing due to their intrinsic magnetic, electrochemical, and optical properties. However, engineered multicomponent magnetic nanoparticle-based current biosensors that offer the advantages of excellent stability in a complex biomatrix; easy and alterable biorecognition of ligands, antibodies, and receptor molecules; and unified point-of-care integration have yet to be achieved. This review introduces the recent advances in superparamagnetic nanostructures for electrochemical and optical biosensing for disease-specific biomarkers. This review emphasizes the synthesis, biofunctionalization, and intrinsic properties of nanomaterials essential for robust, ultrasensitive biosensing. With a particular emphasis on nanostructure-based electrochemical and optical detection of disease-specific biomarkers such as nucleic acids (DNA and RNA), proteins, autoantibodies, and cells, this review also chronicles the needs and challenges of nanoarchitecture-based detection. These summaries provide further insights for researchers to inspire their future work on the development of nanostructures for integrating into biosensing and devices for a broad field of applications in analytical sensing and in clinic
Cross Stacking of Nanopatterned PEDOT Films for Use as Soft Electrodes
Cross
stacking of nanopatterned conductive polymer film was explored using
a sacrificial soft template made of nanopatterned polystyrene (PS)
film as a guide for nanopatterned conductive polymer film. For use
as a conductive film, the PS pattern was filled with polyÂ(3,4-ethylenedioxythiophene)
(PEDOT), and then completely removed, to generate single-patterned
PEDOT (SPDOT) film having a conductivity of 1079 S/cm, which was comparable
to the pristine unpatterned PEDOT (UPDOT) film on a glass slide. SPDOT
layers were stacked across each other to form double-layered (DPDOT)
and multiple-layered patterned PEDOT film on a glass slide or polymeric
substrate. The patterned PEDOT film showed enhanced optical and electrochemical
activity; specifically as compared to the UPDOT film on a glass slide,
the DPDOT film showed an increase in reflectance and an enhanced electrochemically
active surface by 23.4% and 32.8%, respectively. The patterned PEDOT
film on a polymer substrate showed high bendability up to being completely
folded and maintained its conductivity for over 10 000 cycles
of bending. The patterned PEDOT layers were applied to dye-sensitized
solar cells (DSSCs) as a transparent conductive oxide (TCO)-free counter
electrode. An N719-based DSSC with a DPDOT film recorded a photoconversion
efficiency of 7.54%, which is one of the highest values among the
TCO-free DSSCs based on a PEDOT counter electrode
Photothermally Activated Pyroelectric Polymer Films for Harvesting of Solar Heat with a Hybrid Energy Cell Structure
Large-Scale Synthesis of MOF-Derived Superporous Carbon Aerogels with Extraordinary Adsorption Capacity for Organic Solvents
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Carbon aerogels (CAs) with 3D interconnected networks hold promise for application in areas such as pollutant treatment, energy storage, and electrocatalysis. In spite of this, it remains challenging to synthesize high-performance CAs on a large scale in a simple and sustainable manner. We report an eco-friendly method for the scalable synthesis of ultralight and superporous CAs by using cheap and widely available agarose (AG) biomass as the carbon precursor. Zeolitic imidazolate framework-8 (ZIF-8) with high porosity is introduced into the AG aerogels to increase the specific surface area and enable heteroatom doping. After pyrolysis under inert atmosphere, the ZIF-8/AG-derived nitrogen-doped CAs show a highly interconnected porous mazelike structure with a low density of 24 mg cm−3, a high specific surface area of 516 m2 g−1, and a large pore volume of 0.58 cm−3 g−1. The resulting CAs exhibit significant potential for application in the adsorption of organic pollutants
In-situ fabrication of nanoarchitectured MOF filter for water purification
Sulfate radical (SO )-based advanced oxidation processes (SR-AOPs) hold great promise for water purification due to their strong oxidizing and high selectivity. Recently, metal-organic frameworks (MOFs) as catalysts for peroxymonosulfate (PMS) activation to generate SO have shown a bright future. However, the intrinsic nature of powder MOF nanocrystals, such as brittleness and poor processability, largely disturb their large-scale applications in practical. Herein, we develop an in situ growth method to prepare MOF filters. ZIF-67 in situ growth on the polyacrylonitrile (PAN) fibers lead to the ZIF-67/PAN composite fibers with high loading (up to 50 wt %). The loading ZIF-67 can retain their morphology and structure, which is comparable with that of pristine ZIF-67 powder. The ZIF-67/PAN filter demonstrates a high efficiency for organic pollutants removal by PMS activation. Furthermore, through the fabrication of filtration device, the dynamic catalysis results show the ZIF-67/PAN filter is a promising material for water purification. This work provides a new method for applying MOFs-based functional materials to practical water remediation and other separation applications
Transparent Electrochemical Gratings from a Patterned Bistable Silver Mirror
Silver mirror patterns
were formed reversibly on a polystyrene
(PS)-patterned electrode to produce gratings through the electrochemical
reduction of silver ions. The electrochemical gratings exhibited high
transparency (<i>T</i> > 95%), similar to a see-through
window, by matching the refractive index of the grating pattern with
the surrounding medium. The gratings switch to a diffractive state
upon the formation of a mirror pattern (<i>T</i> < 5%)
with a high diffraction efficiency up to 40%, providing reversible
diffractive gratings. The diffraction state was maintained in the
voltage-off state (V-off) for 40 min, which demonstrated bistable
reversible electrochemical grating (BREG) behavior. By carefully combining
the BREGs through period matching, dual-color switching was achieved
within the full color region, which exhibited three distinct optical
switching states between −2.5, 0, and +2.5 V. The wide range
of light tenability using the metallic BREGs developed herein enabled
IR modulation, NIR light reflection, and on-demand heat transfer
Plasmonic mesoporous AuAg nanospheres with controllable nanostructures
Three kinds of plasmonic mesoporous AuAg (mesoAuAg) nanospheres, including well-alloyed mesoAuAg, hollow mesoAuAg, and core-shell Ag-mesoAu nanospheres, were successfully synthesized by carefully controlling the reduction kinetics of metal precursors in the presence of a functional surfactant, C22H45N+(CH3)2-C3H6-SH(Cl-). The resulting mesoAuAg exhibited a remarkable structure-dependent electrocatalytic performance toward methanol oxidation reaction
Functional mesoporous silica nanoparticles for catalysis and environmental applications
Silica materials are used in a wide range of applications such as catalysis, photocatalysis, CO2 capture, and environmental remediation. These nanomaterials (NMs) have been extensively investigated since the advent of Stöber silica. However, the absence of pores and small surface area of Stöber silica limited its applications. Later, the discovery of MCM-41 type mesoporous silica using surfactants as structural directing agents became revolutionary in the field of silica NMs. This review focuses on the methods used for synthesizing mesoporous silica nanoparticles and their applications in various fields including catalysis (i.e., support for nanoparticle catalysts) and environmental remediation (CO to CO2 conversion, volatile organic compound (VOC) removal, and CO2 capture). The current issues/challenges in realizing the practical applications of these conventional materials are also highlighted. This review also compares the characteristics and applications of MCM-41, SBA-15, and KCC-1 to demonstrate the effect of the morphology and pore architecture of silica on the properties of silica-based NMs. The scope for future developments in the synthesis and applications of silica materials with different pore sizes and morphologies is discussed
Metal-incorporated mesoporous oxides: synthesis and applications
Mesoporous oxides are outstanding metal nanoparticle catalyst supports owing to their well-defined porous structures. Such mesoporous architectures not only prevent the aggregation of metal nanoparticles but also enhance their catalytic performance. Metal/metal oxide heterojunctions exhibit unique chemical and physical properties because of the surface reconstruction around the junction and electron transfer/interaction across the interface. This article reviews the methods used for synthesizing metal-supported hybrid nanostructures and their applications as catalysts for environmental remediation and sensors for detecting hazardous materials
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