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A gold nanogap substrate was used to measure the thiram and carbaryl residues in various fruit juices using surface-enhanced Raman scattering (SERS). The gold nanogap substrates can detect carbaryl and thiram with limits of detection of 0.13 ppb (0.13 μgkg -1 ) and 0.22 ppb (0.22 μgkg -1 ). Raw SERS data were first preprocessed to reduce noise and undesirable effects and, were later used for model creation, implementing classification, and regression analysis techniques. The partial least-squares regression models achieved the highest prediction correlation coefficient (R 2 ) of 0.99 and the lowest root mean square of prediction value below 0.62 ppb for both pesticide-infected juice samples. Furthermore, to differentiate between juice samples contaminated by both pesticides and control (pesticide-free), logistic-regression classification models were produced and achieved the highest classification accuracies of 100% and 99% for contaminated juice containing thiram and 100% accurate results for contaminated juice containing carbaryl. This indicates that the gold nanogap surface has significant potential for achieving high sensitivity in detecting trace contaminants in food samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The discharge of toxic dye effluents from industry is a major concern for environmental pollution and toxicity. These toxic dyes can be efficiently removed from waste streams using a photocatalysis process involving visible light. Due to its simple synthesis procedure, inexpensive precursor, and robust stability, graphitic carbon nitride (g-C 3 N 4 , or CN) has been used as a visible light responsive catalyst for the degradation of dyes with mediocre performance because it is limited by its low visible light harvesting capability due to its wide bandgap and fast carrier recombination rate. To overcome these limitations and enhance the performance of g-C 3 N 4 , it was coupled with a narrow bandgap copper tin sulfide (CTS) semiconductor to form a p-n heterojunction. CTS and g-C 3 N 4 were selected due to their good stability, low toxicity, ease of synthesis, layered sheet/plate-like morphology, and relatively abundant precursors. Accordingly, a series of copper tin sulfide/graphitic carbon nitride nanocomposites (CTS/g-C 3 N 4 ) with varying CTS contents were successfully synthesized via a simple two-step process involving thermal pyrolysis and coprecipitation for visible-light-induced photocatalytic degradation of methyl orange (MO) dye. The photocatalytic activity results showed that the 50%(wt/wt) CTS/g-C 3 N 4 composite displayed a remarkable degradation efficiency of 95.6% for MO dye under visible light illumination for 120 min, which is higher than that of either pristine CTS or g-C 3 N 4 . The improved performance is attributed to the extended light absorption range (due to the optimized bandgap), effective suppression of photoinduced electron-hole recombination, and improved charge transfer that arose from the formation of a p-n heterojunction, as evidenced by electrochemical impedance spectroscopy (EIS), photocurrent, and photoluminescence results. Moreover, the results of the reusability study showed that the composite has excellent stability, indicating its potential for the degradation of MO and other toxic organic dyes from waste streams., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

MXene is widely used in the construction of optoelectronic interfaces due to its excellent properties. However, the hydrophilicity and metastable surface of MXene lead to its oxidation behavior, resulting in the degradation of its various properties, which seriously limits its practical application. In this work, a 2D metal-organic framework (2D MOF) with matching 2D morphology, excellent stability performance, and outstanding optoelectronic performance is grown in situ on the MXene surface through heterojunction engineering to suppress the direct contact between reactive molecules and the inner layer material without affecting the original advantages of MXene. The photoelectric dual gain MXene@MOF heterojunction is confirmed. As a photoelectric material, its properties are highly suitable for the demand of interface sensitization layer materials of surface plasmon resonance (SPR). Therefore, using SPR as a platform for the application of this interface material, the performance of MXene@MOF and its potential mechanism to enhance SPR are analyzed in depth using experiments combined with simulation calculations (FDTD/DFT). Finally, the MXene@MOF/peptides-SPR sensor is constructed for rapid and sensitive detection of the cancer marker exosomes to explore its potential in practical applications. This work offers a forward-looking strategy for the design of interface materials with excellent photoelectric performance., (© 2023 Wiley‐VCH GmbH.)

The slow photon effect in inverse opal photonic crystals represents a promising approach to manipulate the interactions between light and matter through the design of material structures. This study introduces a novel ordered inverse opal photonic crystal (IOPC) sensitized with perovskite quantum dots (PQDs), demonstrating its efficacy for efficient visible-light-driven H 2 generation via water splitting. The rational structural design contributes to enhanced light harvesting. The sensitization of the IOPC with PQDs improves optical response performance and enhances photocatalytic H 2 generation under visible light irradiation compared to the IOPC alone. The designed photoanode exhibits a photocurrent density of 3.42 mA cm -2 at 1.23 V vs RHE. This work advances the rational design of visible light-responsive photocatalytic heterostructure materials based on wide band gap metal oxides for photoelectrochemical applications., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Fe-based nanostructures have possessed promising properties that make it suitable for chiral sensing and imaging applications owing to their ultra-small size, non-toxicity, biocompatibility, excellent photostability, tunable fluorescence, and water solubility. This review summarizes the recent research progress in the field of Fe-based nanostructures and places special emphases on their applications in chiral sensing and imaging. The synthetic strategies to prepare the targeted Fe-based structures were also introduced. The chiral sensing and imaging applications of the nanostructures are discussed in details., (© 2023 Wiley Periodicals LLC.)

Solid-state batteries are commonly acknowledged as the forthcoming evolution in energy storage technologies. Recent development progress for these rechargeable batteries has notably accelerated their trajectory toward achieving commercial feasibility. In particular, all-solid-state lithium-sulfur batteries (ASSLSBs) that rely on lithium-sulfur reversible redox processes exhibit immense potential as an energy storage system, surpassing conventional lithium-ion batteries. This can be attributed predominantly to their exceptional energy density, extended operational lifespan, and heightened safety attributes. Despite these advantages, the adoption of ASSLSBs in the commercial sector has been sluggish. To expedite research and development in this particular area, this article provides a thorough review of the current state of ASSLSBs. We delve into an in-depth analysis of the rationale behind transitioning to ASSLSBs, explore the fundamental scientific principles involved, and provide a comprehensive evaluation of the main challenges faced by ASSLSBs. We suggest that future research in this field should prioritize plummeting the presence of inactive substances, adopting electrodes with optimum performance, minimizing interfacial resistance, and designing a scalable fabrication approach to facilitate the commercialization of ASSLSBs., (© 2024. The Author(s).)

The need for the development of soft materials capable of stably adhering to nerve tissues without any suturing followed by additional damages is at the fore at a time when success in postoperative recovery depends largely on the surgical experience and/or specialized microsuturing skills of the surgeon. Despite fully recognizing such prerequisite conditions, designing the materials with robust adhesion to wet nerves as well as acute/chronic anti-inflammation remains to be resolved. Herein, a sticky and strain-gradient artificial epineurium (SSGAE) that overcomes the most critically challenging aspect for realizing sutureless repair of severely injured nerves is presented. In this regard, the SSGAE with a skin-inspired hierarchical structure entailing strain-gradient layers, anisotropic Janus layers including hydrophobic top and hydrophilic bottom surfaces, and synergistic self-healing capabilities enables immediate and stable neurorrhaphy in both rodent and nonhuman primate models, indicating that the bioinspired materials strategy significantly contributes to translational medicine for effective peripheral nerve repair., (© 2024 Wiley‐VCH GmbH.)

The introduction of noble metal nanoparticles with good LSPR characteristics can greatly improve the sensitivity of SPR through resonance coupling effect. The plasma resonance response and optical properties of film coupling nanoparticle systems largely depends on the ingenious design of gap structures. Nucleic acid nanostructures have good stability, flexibility, and high biocompatibility, making them ideal materials for gap construction. 2D MOF (Cu-Tcpp) has a large conjugated surface similar to graphene, which can provide a stable substrate for the directional fixation of nucleic acid nanostructures. However, research on gap coupling plasmon based on nucleic acid nanostructures and 2D MOF is still rarely reported. By integrating the advantages of Cu-Tcpp assembled film and DNA tetrahedron immobilization, a nano gap with porous scaffold structure between the gold film and gold nanorod was build. The rigidity of DNA tetrahedron can precisely control the gap size, and its unique programmability allows us to give the coupling structure greater flexibility through the design of nucleic acid chain. The experimental results and FDTD simulation show that the film coupling nanoparticle systems constructed with DNA tetrahedrons greatly enhance the electric field strength near the chip surface and effectively improve the sensitivity of SPR. This research shows the huge potential of nucleic acid nanomaterials in the construction of SPR chip surface microstructures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Copper tin sulfide, Cu 4 SnS 4 (CTS), a ternary transition-metal chalcogenide with unique properties, including superior electrical conductivity, distinct crystal structure, and high theoretical capacity, is a potential candidate for supercapacitor (SC) electrode materials. However, there are few studies reporting the application of Cu 4 SnS 4 or its composites as electrode materials for SCs. The reported performance of the Cu 4 SnS 4 electrode is insufficient regarding cycle stability, rate capability, and specific capacity; probably resulting from poor electrical conductivity, restacking, and agglomeration of the active material during continued charge-discharge cycles. Such limitations can be overcome by incorporating graphene as a support material and employing a binder-free, facile, electrodeposition technique. This work reports the fabrication of a copper tin sulfide-reduced graphene oxide/nickel foam composite electrode (CTS-rGO/NF) through stepwise, facile electrodeposition of rGO and CTS on a NF substrate. Electrochemical evaluations confirmed the enhanced supercapacitive performance of the CTS-rGO/NF electrode compared to that of CTS/NF. A remarkably improved specific capacitance of 820.83 F g -1 was achieved for the CTS-rGO/NF composite electrode at a current density of 5 mA cm -2 , which is higher than that of CTS/NF (516.67 F g -1 ). The CTS-rGO/NF composite electrode also exhibited a high-rate capability of 73.1% for galvanostatic charge-discharge (GCD) current densities, ranging from 5 to 12 mA cm -2 , and improved cycling stability with over a 92% capacitance retention after 1000 continuous GCD cycles; demonstrating its excellent performance as an electrode material for energy storage applications, encompassing SCs. The enhanced performance of the CTS-rGO/NF electrode could be attributed to the synergetic effect of the enhanced conductivity and surface area introduced by the inclusion of rGO in the composite., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The photodegradation of organic pollutants using metal oxide-based catalysts has drawn great attention as an effective method for wastewater treatment. In this study, zinc oxide nanoparticles (ZnO NPs) and zinc oxide/copper oxide nanocomposites (ZnO/CuO NCs) were fabricated using the leaf extract of Croton macrostachyus as a nontoxic, natural reducing and stabilizing agent. The synthesized samples were characterized by employing X-ray diffraction, microscopic, spectroscopic, and electrochemical methods. The results confirmed the successful synthesis of ZnO NPs and ZnO/CuO NCs with well-defined crystalline structures and morphologies. The prepared samples were tested for the photodegradation of methylene blue (MB) dye under visible light irradiation. Compared to ZnO NPs, ZnO/CuO NCs showed greatly improved photocatalytic performances, particularly with the sample prepared with the 20 mol % Cu precursor (97.02%). The enhancement could be related to the formed p-n heterojunction, which can suppress the recombination of charge carriers and extend the photoresponsive range. A theoretical study of the photocatalytic activity of ZnO/CuO NCs against MB dye degradation was also conducted by using COMSOL Multiphysics software. The results of the simulation are in reasonable agreement with those of the experiment. This study contributes to the development of sustainable and effective photocatalytic materials that are suitable for application in environmental remediation, particularly in the treatment of wastewater., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The measurement of biosignals in the clinical and healthcare fields is fundamental; however, conventional electrodes pose challenges such as incomplete skin contact and skin-related issues, hindering accurate biosignal measurement. To address these challenges, conductive hydrogels, which are valuable owing to their biocompatibility and flexibility, have been widely developed and explored for electrode applications. In this study, we fabricated a conductive hydrogel by mixing polyethylene glycol diacrylate (PEGDA) with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) polymers dissolved in deionized water, followed by light-triggered crosslinking. Notably, this study pioneered the use of a PEGDA-PEDOT:PSS hydrogel for electrocardiogram (ECG) monitoring- a type of biosignal. The resulting PEGDA-PEDOT:PSS hydrogel demonstrated remarkable conductivity while closely approximating the modulus of skin elasticity. Additionally, it demonstrated biocompatibility and a high signal-to-noise ratio in the waveforms. This study confirmed the exceptional suitability of the PEGDA-PEDOT:PSS hydrogel for accurate biosignal measurements with potential applications in various wearable devices designed for biosignal monitoring.

The rapid and efficient detection of chloride (Cl - ) ions is crucial in a variety of fields, making the development of advanced sensing methods such as colorimetric sensors an imperative advancement in analytical chemistry. Herein, a novel, selective, and straightforward paper-based colorimetric sensing platform has been developed utilizing an amorphous photonic array (APA) of magnetoplasmonic Ag@Fe 3 O 4 nanoparticles (MagPlas NPs) for the detection of Cl - in water. Taking advantage of the highly responsive APA, the key principle of this sensing method is based on the chemical reaction between Ag + and Cl - , which results in the precipitation of high-refractive index (RI) AgCl. This assay, distinct from typical plasmonic sensors that rely heavily on nanoparticle aggregation/anti-aggregation, is premised on the precipitation reaction of Ag + and Cl - . In the presence of Cl - , a rapid, distinctive color alteration from royal purple to a dark sky blue is visually observable within a short time of a few minutes, eliminating the necessity for any surface modification procedures. Comprehensive assessments substantiated that these sensors display commendable sensitivity, selectivity, and stability, thereby establishing their effective applicability for Cl - analysis in various technological fields., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

A feasible nanoscale framework of heterogeneous plasmonic materials and proper surface engineering can enhance photoelectrochemical (PEC) water-splitting performance owing to increased light absorbance, efficient bulk carrier transport, and interfacial charge transfer. This article introduces a new magnetoplasmonic (MagPlas) Ni-doped Au@Fe x O y nanorods (NRs) based material as a novel photoanode for PEC water-splitting. A two stage procedure produces core-shell Ni/Au@Fe x O y MagPlas NRs. The first-step is a one-pot solvothermal synthesis of Au@Fe x O y . The hollow Fe x O y nanotubes (NTs) are a hybrid of Fe 2 O 3 and Fe 3 O 4 , and the second-step is a sequential hydrothermal treatment for Ni doping. Then, a transverse magnetic field-induced assembly is adopted to decorate Ni/Au@Fe x O y on FTO glass to be an artificially roughened morphologic surface called a rugged forest, allowing more light absorption and active electrochemical sites. Then, to characterize its optical and surface properties, COMSOL Multiphysics simulations are carried out. The core-shell Ni/Au@Fe x O y MagPlas NRs increase photoanode interface charge transfer to 2.73 mAcm -2 at 1.23 V RHE. This improvement is made possible by the rugged morphology of the NRs, which provide more active sites and oxygen vacancies as the hole transfer medium. The recent finding may provide light on plasmonic photocatalytic hybrids and surface morphology for effective PEC photoanodes., (© 2023 Wiley-VCH GmbH.)

Skin has a dynamic surface and offers essential information through biological signals originating from internal organs, blood vessels, and muscles. Soft and stretchable bioelectronics can be used in wearable machines for long-term stability and to continuously obtain distinct bio-signals in conjunction with repeated expansion and contraction with physical activities. While monitoring bio-signals, the electrode and skin must be firmly attached for high signal quality. Furthermore, the signal-to-noise ratio (SNR) should be high enough, and accordingly, the ionic conductivity of an adhesive hydrogel needs to be improved. Here, we used a chitosan-alginate-chitosan (CAC) triple hydrogel layer as an interface between the electrodes and the skin to enhance ionic conductivity and skin adhesiveness and to minimize the mechanical mismatch. For development, thermoplastic elastomer Styrene-Ethylene-Butylene-Styrene (SEBS) dissolved in toluene was used as a substrate, and gold nanomembranes were thermally evaporated on SEBS. Subsequently, CAC triple layers were drop-casted onto the gold surface one by one and dried successively. Lastly, to demonstrate the performance of our electrodes, a human electrocardiogram signal was monitored. The electrodes coupled with our CAC triple hydrogel layer showed high SNR with clear PQRST peaks.

In wearable bioelectronics, various studies have focused on enhancing prosthetic control accuracy by improving the quality of physiological signals. The fabrication of conductive composites through the addition of metal fillers is one way to achieve stretchability, conductivity, and biocompatibility. However, it is difficult to measure stable biological signals using these soft electronics during physical activities because of the slipping issues of the devices, which results in the inaccurate placement of the device at the target part of the body. To address these limitations, it is necessary to reduce the stiffness of the conductive materials and enhance the adhesion between the device and the skin. In this study, we measured the electromyography (EMG) signals by applying a three-layered hydrogel structure composed of chitosan-alginate-chitosan (CAC) to a stretchable electrode fabricated using a composite of styrene-ethylene-butylene-styrene and eutectic gallium-indium. We observed stable adhesion of the CAC hydrogel to the skin, which aided in keeping the electrode attached to the skin during the subject movement. Finally, we fabricated a multichannel array of CAC-coated composite electrodes (CACCE) to demonstrate the accurate classification of the EMG signals based on hand movements and channel placement, which was followed by the movement of the robot arm.

Background: Heterocyclic analogs of curcumin have a wide range of therapeutic potential and the ability to control the activity of a variety of metabolic enzymes., Methods: 1 H-NMR and 13 C-NMR spectroscopic techniques were used to determine the structures of synthesized compounds. The agar disc diffusion method and α-amylase inhibition assay were used to examine the antibacterial and anti-diabetic potential of the compounds against α-amylase enzyme inhibitory activity, respectively. DPPH-free radical scavenging and lipid peroxidation inhibition assays were used to assess the in vitro antioxidant potential., Results and Discussion: In this work, nine heterocyclic analogs derived from curcumin precursors under ultrasonic irradiation were synthesized in excellent yields (81.4-93.7%) with improved reaction time. Results of antibacterial activities revealed that compounds 8, and 11 displayed mean inhibition zone of 13.00±0.57, and 19.66±00 mm, respectively, compared to amoxicillin (12.87±1.41 mm) at 500 μg/mL against E. coli , while compounds 8, 11 and 16 displayed mean inhibition zone of 17.67±0.57, 14.33±0.57 and 23.33±00 mm, respectively, compared to amoxicillin (13.75±1.83 mm) at 500 μg/mL against P. aeruginosa . Compound 11 displayed a mean inhibition zone of 11.33±0.57 mm compared to amoxicillin (10.75±1.83 mm) at 500 μg/mL against S. aureus . Compound 11 displayed higher binding affinities of -7.5 and -8.3 Kcal/mol with penicillin-binding proteins (PBPs) and β -lactamases producing bacterial strains, compared to amoxicillin (-7.2 and -7.9 Kcal/mol, respectively), these results are in good agreement with the in vitro antibacterial activities. In vitro antidiabetic potential on α -amylase enzyme revealed that compounds 11 (IC 50 =7.59 µg/mL) and 16 (IC 50 =4.08 µg/mL) have higher inhibitory activities than acarbose (IC 50 =8.0 µg/mL). Compound 8 showed promising antioxidant inhibition efficacy of DPPH (IC 50 = 2.44 g/mL) compared to ascorbic acid (IC 50 =1.24 g/mL), while compound 16 revealed 89.9±20.42% inhibition of peroxide generation showing its potential in reducing the development of lipid peroxides. In silico molecular docking analysis, results are in good agreement with in vitro biological activity. In silico ADMET profiles suggested the adequate oral drug-likeness potential of the compounds without adverse effects., Conclusion: According to our findings, both biological activities and in silico computational studies results demonstrated that compounds 8, 11, and 16 are promising α -amylase inhibitors and antibacterial agents against E. coli , P. aeruginosa , and S. aureus , whereas compound 8 was found to be a promising antioxidant agent., Competing Interests: The authors declare no conflicts of interest in this work., (© 2023 Zelelew et al.)

In this study, a Ag/WO 3 /InGaN hybrid heterostructure was successfully developed by sputtering and molecular beam epitaxy techniques, to obtain unique Ag nanospheres adorned with cauliflower-like WO 3 nanostructure over the InGaN nanorods (NRs). Exploiting the localized surface plasmon resonance of Ag, the Ag/WO 3 /InGaN heterostructure exhibited superior photoabsorption ability in the visible region (400-700 nm) of the solar spectrum, with a surface plasmon resonance band centered around 440 nm. Comprehensive analysis through photoluminescence spectroscopy, photocurrent measurements, and electrochemical impedance spectroscopy revealed that the Ag/WO 3 /InGaN hybrid heterostructure significantly enhances the charge carrier separation and transfer kinetics leading to improved overall photoelectrochemical (PEC) performance. The photocurrent density of the Ag/WO 3 /InGaN photoanode is 1.17 mA/cm 2 , which is about 2.72 times higher than that of pure InGaN NRs under visible light irradiation. The photoanode exhibited excellent stability for about 12 h. From the study, it has been found that the maximum applied bias photon-to-current efficiency (ABPE) is ∼1.67% at the applied bias of 0.6 V. The improved PEC water splitting efficiency of the Ag/WO 3 /InGaN photoanode is attributed to the synergistic effects of localized surface plasmon resonance (LSPR), efficient charge carrier separation and transport, and the presence of a Schottky junction. Consequently, the plasmonic metal-assisted heterojunction-based semiconductor Ag/WO 3 /InGaN demonstrates immense potential for practical applications in photoelectrochemical water splitting.

The rational synthesis and tailoring of metal-organic frameworks (MOFs) with multifunctional micro/nanoarchitectures have emerged as a subject of significant academic interest owing to their promising potential for utilization in advanced energy storage devices. Herein, we explored a category of three-dimensional (3D) NiCo 2 S 4 nanospikes that have been integrated into a 1D Fe 3 C microarchitecture using a chemical surface transformation process. The resulting electrode materials, i.e. , Fe 3 C@NiCo 2 S 4 nanospikes, exhibit immense potential for utilization in high-performance hybrid supercapacitors. The nanospikes exhibit an elevated specific capacity (1894.2 F g -1 at 1 A g -1 ), enhanced rate capability (59%), and exceptional cycling stability (92.5% with 98.7% Coulombic efficiency) via a charge storage mechanism reminiscent of a battery. The augmented charge storage characteristics are attributed to the collaborative features of the active constituents, amplified availability of active sites inherent in the nanospikes, and the proficient redox chemical reactions of multi-metallic guest species. When using nitrogen-doped carbon nanofibers as the anode to fabricate hybrid supercapacitors, the device exhibits high energy and power densities of 62.98 Wh kg -1 and 6834 W kg -1 , respectively, and shows excellent long-term cycling stability (95.4% after 5000 cycles), which affirms the significant potential of the proposed design for applications in hybrid supercapacitors. The DFT study showed the strong coupling of the oxygen from the electrolyte OH - with the metal atom of the nanostructures, resulting in high adsorption properties that facilitate the redox reaction kinetics.

Here, the structural, optical, and adsorptive behaviors of Ni 0.075-x Mn x Al 0.025 (OH) 2 (CO 3 ) 0.0125 ·yH 2 O (Ni-Mn/Al) layered double hydroxides (LDHs) are investigated to capture fluoride from aqueous media. The 2D mesoporous plate-like Ni-Mn/Al LDHs are successfully prepared via a co-precipitation method. The molar ratio of divalent to trivalent cations is maintained at 3:1 and the pH at 10. The X-ray diffraction (XRD) results confirm that the samples consist of pure LDH phases with a basal spacing of 7.66 to 7.72 Å, corresponding to the (003) planes at 2 θ of 11.47 o and the average crystallite sizes of 4.13 to 8.67 nm. The plate-like Mn-doped Ni-Al LDH consists of many superimposed nanosheets with a size of 9.99 nm. Energy-dispersive X-ray and X-ray photoelectron spectroscopies confirm the incorporation of Mn 2+ into the Ni-Al LDH. UV-vis diffuse reflectance spectroscopy results indicate that incorporating Mn 2+ into LDH enhances its interaction with light. The experimental data from the batch fluoride adsorption studies are subjected to kinetic models such as pseudo-first order and pseudo-second order. The kinetics of fluoride retention on Ni-Mn/Al LDH obey the pseudo-second-order model. The Temkin equation well describes the equilibrium adsorption of fluoride. The results from the thermodynamic studies also indicate that fluoride adsorption is exothermic and spontaneous., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Global Challenges published by Wiley‐VCH GmbH.)

Trace-level ammonia gas in air was analyzed using a fiber-based compact cavity ring-down spectrometer (CRDS). For the compact spectrometer, a 20 cm linear cavity with two high reflectivity (>99.999 % ) mirrors was employed. The laser frequency was locked to the cavity resonance by using frequency shifted (160 MHz) optical feedback. For N H 3 detection, a strong absorption band at 1513.98 nm with an absorption cross section of 3.3⋅10 -21 c m / m o l e c u l e was used. As a result, a detection sensitivity of ∼0.1 p p b (3- σ ) was achieved for N H 3 within 10 s.

Rationale: Exosomes contain biomarkers such as proteins and lipids that help in understanding normal physiology and diseases. Lipids, in particular, are infrequently studied using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) for biomarker discovery. In this study, MALDI was equipped with a high-resolution MS to investigate exosomal lipids from human serum., Methods: Exosomal lipids were profiled using MALDI with Fourier-transform ion cyclotron resonance (FTICR)-MS. Four matrices (i.e., α-cyano-4-hydroxycinnamic acid [CHCA], 2,5-dihydroxybenzoic acid, sinapinic acid, and graphene oxide [GO]) and three sample preparation methods (i.e., dried droplet, thin layer, and two layer) were compared for the number of lipid species detected and the relative abundance of each lipid from human serum and human serum exosomes., Results: In sum, 172 and 89 lipid species were identified from human serum and human serum exosomes, respectively, using all the methods. The highest number of exosome lipid species, 69, was detected using the CHCA matrix, whereas only 8 exosome lipid species were identified using the GO matrix. Among the identified lipid species, phosphatidylcholine was identified most frequently, probably due to the use of a positive ion mode., Conclusions: Exosomes and human serum showed comparable lipid profiles as determined using MALDI-FTICR-MS. These findings provide a new perspective on exosomal lipidomics analysis and may serve as a foundation for future lipidomics-based biomarker research using MALDI-FTICR-MS., (© 2022 John Wiley & Sons Ltd.)

Two-dimensional (2D) iron oxide-hydroxide (FeOOH) nanomaterials as low-cost and environmental-friendly composites are promising materials for application in heavy metal elimination. However, developing 2D FeOOH adsorbents with high adsorption capacity and excellent durability toward Cr (VI) removal is still a challenge due to the intrinsically non-layered structure. Here, a novel polyethyleneimine (PEI) functionalized 2D single-layer nano-raft-like α-FeOOH (α-FeOOH NF) consisted of parallel-aligned ultrathin nanowires was obtained via a facile one-pot hydrothermal approach. It was found that the 2D α-FeOOH NF nanostructure was formed by an in-plane iterative self-assembly mechanism, where α-FeOOH nanoparticles acted as intermediates and iterative seeds with anisotropic growth. The as-prepared 2D α-FeOOH NF possessed porous structure and high surface area, which provided a strong ability to capture the Cr (VI) ions in water. Benefiting from the unique structure and PEI modification, it exhibited fast adsorption kinetic rate, high reusability, and high adsorption capacity toward Cr(VI) removal. The removal mechanism involved adsorption and reduction process. Besides, the molecular dynamic simulations disclosed a facet-dependent Cr(VI) adsorption behavior of α-FeOOH. The maximum adsorption capacity was 67.1 mg/g and the removal efficiency still maintained 83.9 % in the fifth cycle. This work demonstrated that 2D α-FeOOH NF could be a promising adsorbent for Cr(VI) removal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

CuO-ZnO nanocomposites (NCs) were synthesized using an aqueous extract of Verbascum sinaiticum Benth. (GH) plant. X-ray diffraction (XRD), spectroscopic, and microscopic methods were used to explore the crystallinity, optical properties, morphology, and other features of the CuO-ZnO samples. Furthermore, catalytic performances were investigated for methylene blue (MB) degradation and 4-nitrophenol (4-NP) reduction. According to the results, CuO-ZnO NCs with 20 wt % CuO showed enhanced photocatalytic activity against MB dye with a 0.017 min -1 rate constant compared to 0.0027 min -1 for ZnO nanoparticles (NPs). Similarly, a ratio constant of 5.925 min -1 g -1 4-NP reductions was achieved with CuO-ZnO NCs. The results signified enhanced performance of CuO-ZnO NCs relative to ZnO NPs. The enhancement could be due to the synergy between ZnO and CuO, resulting in improved absorption of visible light and reduced electron-hole (e - /h + ) recombination rate. In addition, variations in the CuO content affected the performance of the CuO-ZnO NCs. Thus, the CuO-ZnO NCs prepared using V. sinaiticum Benth. extract could make the material a desirable catalyst for the elimination of organic pollutants., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Porous core-shell nanoparticles (NPs) have emerged as a promising material for broad ranges of applications in catalysts, material chemistry, biology, and optical sensors. Using a typical Ag core-Fe 3 O 4 shell NP, a.k.a., magnetoplasmonic (MagPlas) NP, two porous shell models were prepared: i.e. , Ag@Fe 3 O 4 NPs and its SiO 2 -covered NPs (Ag@Fe 3 O 4 @SiO 2 ). We suggested using cyclic voltammetry (CV) to provide unprecedented insight into the porosity of the core-shell NPs caused by the applied potential, resulting in the selective redox activities of the core and porous shell components of Ag@Fe 3 O 4 NPs and Ag@Fe 3 O 4 @SiO 2 NPs at different cycles of CV. The porous and nonporous core-shell nanostructures were qualitatively and quantitatively determined by the electrochemical method. The ratio of the oxidation current peak (μA) of Ag to Ag + in the porous shell to that in the SiO 2 coated (nonporous) shell was 400:3.2. The suggested approach and theoretical background could be extended to other types of multicomponent NP complexes.

Fingerprint-inspired elastomeric grating meta-skin (EGMS) is herein fabricated to investigate the chirality of fingerprints. The EGMS is made by a facile nanoimprinting method with a diffraction grating as a template using polydimethylsiloxane, followed by gold deposition. The chirality of the surface is caused by symmetry breaking, induced by the pattern ( P ) and curvature ( T ). Furthermore, the chiroptical properties of EGMS are reconfigurable through the control of the skew angle (θ), which is the angle between P and T . The chiroptical properties of a fingerprint are also shown and interpreted in this perspective. On the basis of the results, we suggest the strategy to impart chirality on the surface, which is reconfigurable by controlling P and T . It will be a useful method to produce chirality in membranes, thin films, metasurfaces, and 2D nanomaterials, as well as advance biometric recognition.

One-dimensional hybrid nanostructures composed of a plasmonic gold nanowire core covered by a shell of magnetic oxide nanoparticles (Au@Fe x O y NWs) were synthesized by a one-pot solvothermal synthesis process. The effects of reaction temperature, time, reducing agent, and precursor as well as postsynthesis treatment were optimized to produce highly uniform NWs with a diameter of 226 ± 25 nm and a plasmonic core aspect ratio of 25 to 82. By exploiting the interaction of NWs with an external magnetic field, precise arrangements into highly periodic photonic structures were achieved, which can generate distinctive structural colors that are vividly iridescent and polarization-sensitive. Furthermore, a Bouligand-type chiral nematic film consisting of multistacked unidirectional layers of achiral NWs was fabricated using a modified layer-by-layer deposition method, which displays circular dichroism (CD) and chiral sensing capability. The addition of bovine serum albumin (BSA) as a model protein analyte induced a concentration-dependent wavelength shift of CD peaks. These intriguing properties of magnetoplasmonic anisotropic NWs and their self-assemblies could be consequently valuable for developing nature-inspired structural color imprints as well as solid-state chiral sensing devices.

There are usually trade-offs between maximizing the color saturation and brightness and minimizing the angle-dependent effect in structural colors. Here, a magnetic field-induced assembly for the rapid formation of scalable, uniform amorphous photonic arrays (APAs) featuring unique structural colors is demonstrated. The magnetic field plays a fundamental role in photonic film formation, making this assembly technology versatile for developing structural color patterns on arbitrary substrates. The synergistic combination of surface plasmonic resonance of the Ag core and broadband light absorption of high refractive index (RI) Fe 3 O 4 shell in hybrid magnetoplasmonic nanoparticles (MagPlas NPs) enables breaking the trade-offs to produce brilliant, noniridescent structural colors with high tunability and responsiveness. These features enable the fabrication of various types of highly sensitive and reliable colorimetric sensors for naked-eye detection without sophisticated instruments. Furthermore, large-scale structural color patterns are effortlessly achieved, demonstrating the high potential of the present approach for full-spectrum displays, active coatings, and rewritable papers., (© 2022 Wiley-VCH GmbH.)

Leukocyte cell-derived chemotaxin 2 (LECT2) has been proved to be a potential biomarker for the diagnosis of liver fibrosis. In this work, a sensitive surface plasmon resonance (SPR) assay for LECT2 analysis was developed. Tyrosine kinase with immune globulin-like and epidermal growth factor-like domains 1 (Tie1) is an orphan receptor of LECT2 with a C-terminal Fc tag, which is far away from the LECT2 binding sites. The Fc aptamer was intentionally used to capture the Tie1 through its Fc tag, connecting with Fe 3 O 4 -coated silver magnetic nanoparticles (Ag@MNPs) and ensuring the LECT2 binding site to be outward. Attributed to the orientation nature of the captured protein, Ag@MNPs were able to enhance the SPR signal. A sensitive LECT2 sensor was successfully fabricated with a detection limit of 10.93 pg/mL. The results showed that the immobilization method improved the binding efficiency of Tie1 protein. This strategy could be extended to attach antibodies or recombinant Fc label proteins to Fc aptamer-based nanoparticles.

The global pandemic of COVID-19 is an example of how quickly a disease-causing virus can take root and threaten our civilization. Nowadays, ultrasensitive and rapid detection of contagious pathogens is in high demand. Here, we present a novel hierarchically porous 3-dimensional magnetic molybdenum trioxide-polydopamine-gold functionalized nanosphere (3D mag-MoO 3 -PDA@Au NS) composed of plasmonic, semiconductor, and magnetic nanoparticles as a multifunctional nanosculptured hybrid. Based on the synthesized 3D mag-MoO 3 -PDA@Au NS, a universal "plug and play" biosensor for pathogens is proposed. Specifically, a magnetically-induced nanogap-enhanced Raman scattering (MINERS) detection platform was developed using the 3D nanostructure. Through a magnetic actuation process, the MINERS system overcomes Raman signal stability and reproducibility challenges for the ultrasensitive detection of SARS-CoV-2 spike protein over a wide dynamic range up to a detection limit of 10 -15 g mL -1 . The proposed MINERS platform will facilitate the broader use of Raman spectroscopy as a powerful analytical detection tool in diverse fields., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Recent research has shown that graphene as a novel "green" antibacterial material possess excellent antibacterial properties with no risk of bacterial resistance for daily life due to its physical damage-based bactericidal mechanism. Therefore, an increasing amount of research has been focused towards evaluating the antibacterial effects of graphene and graphene-based hybrid materials. In this chapter, we reviewed the antibacterial activity and mechanism of graphene-based nanomaterials and highlighted the importance of size, morphology, and composites in the application of antibacterial materials development. Finally, we made a summary and outlook on this research field., (© 2022. Springer Nature Singapore Pte Ltd.)

Acrolein is a metabolite of cyclophosphamide (CYP), an alkylating agent used for a wide range of benign and malignant diseases. CYP treatments are known to trigger hemorrhagic cystitis in patients and animals. Significant effort has been made to prevent CYP/acrolein-induced cystitis, while still maintaining its therapeutic benefits. As a result, supplementary therapeutic options to mediate the protective role against CYP/acrolein and lower doses of CYP are currently given to targeted patients, as compared to past treatments. There is still a need to further study the effects of the repeated low-dose CYP/acrolein on the pathophysiology of the urinary bladder. In our study, a one-time treatment of acrolein and repeated low-dose acrolein triggered the thickening of the smooth muscle and lamina propria in the urinary bladder of C57BL/6J mice, respectively. The first dose of acrolein did not trigger voiding dysfunction, but the second dose triggered high-volume low-frequency voiding. Interestingly, our new scoring criteria and concurrent behavioral assessment revealed that mice with repeated low-dose acrolein had a wider opening of eyes in response to mechanical stimuli. Our study suggests that clinical symptoms among patients undergoing prolonged low-dose CYP may differ from previously reported symptoms of CYP-induced hemorrhagic cystitis.

Bacillus spores are highly resistant to toxic chemicals and extreme environments. Because some Bacillus species threaten public health, spore inactivation techniques have been intensively investigated. We exposed Bacillus atrophaeus spores to a 266 nm Nd:YVO 4 laser at a laser power of 1 W and various numbers of scans. As a result, the UV laser reduced the viability of Bacillus atrophaeus spores. Although the outer coat of spores remained intact after UV laser irradiation of 720 scans, damage inside the spores was observed. Spore proteins were identified by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry during the course of UV laser irradiation. Photochemical and photothermal processes are believed to be involved in the UV laser sterilization of Bacillus spores. Our findings suggest that a UV laser is capable of sterilizing Bacillus atrophaeus spores.

The coronavirus disease 2019 (COVID-19) pandemic has proved the importance of fast and widespread diagnostic testing to prevent serious epidemics timely. The first-line weapon against rapidly transmitted disease is a quick and massive screening test to isolate patients immediately, preventing dissemination. Here, we described magnetoplasmonic nanozymes (MagPlas NZs), i.e., hierarchically coassembled Fe 3 O 4 -Au superparticles, that are capable of integrating magnetic enrichment and catalytic amplification, thereby the assay can be streamlined amenable to high-throughput operation and achieve ultrahigh sensitivity. Combining this advantage with conventional enzyme-linked immunosorbent assay (ELISA), we propose a MagPlas ELISA for urine-based tuberculosis (TB) diagnosis and anti-TB therapy monitoring, which enables fast (<3 h), and highly sensitive (up to pM with naked-eyes, < 10 fM with plate reader) urinary TB antigen detection. A clinical study with a total of 297 urine samples showed robust sensitivity for pulmonary tuberculosis (85.0%) and extra-pulmonary tuberculosis (52.8%) patients with high specificity (96.7% and 96.9%). Furthermore, this methodology offers a great promise of noninvasive therapeutic response monitoring, which is impracticable in the gold-standard culture method. The MagPlas ELISA showed high sensitivity comparable to the PCR assay while retaining a simple and cheap ELISA concept, thus it could be a promising point-of-care test for TB epidemic control and possibly applied to other acute infections., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Noble metal nanoparticles could provide a significant gain in sensitivity of surface plasmon resonance (SPR) sensor by electromagnetic field coupling between the localized plasmon resonance of nanoparticles and gold film. A facile and cost-effective SPR sensor based on magnetic field-aligned Fe 3 O 4 -coated silver magnetoplasmonic nanoparticles (Ag@MNPs) nanochain (M-Ag@MNPs) was proposed to improve the sensitivity of the sensor, which gave access to detect clinical targets at low concentration. Optimization experiments proved that 80 ng mL -1 M-Ag@MNPs-based SPR sensor showed high refractive index sensitivity and increased detection accuracy and quality factor when comparing with those of bare gold. Sialic acid binding Ig like lectins-15 (Siglec-15) was used as proof of concept to verify the sensitivity enhancement performance of M-Ag@MNPs in the actual detection process. SPR angle shifts of M-Ag@MNPs/gold sensor were significantly higher than those of traditional gold sensor under the same concentration of Siglec-15, which was consistent with previous performance analysis. Also, the detection limit of M-Ag@MNPs/gold sensor was calculated to be 1.36 pg mL -1 . All these results had proved that aligning M-Ag@MNPs onto the gold chip could improve the performance of the SPR sensor and achieve sensitive detection of small amounts of clinical biomarkers., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Recognition of enantiomeric molecules is essential in pharmaceutical and biomedical applications. In this Article, a novel approach is introduced to monitor chiral molecules via a helical magnetic field ( h B ), where chiral-inactive magnetoplasmonic nanoparticles (MagPlas NPs, Ag@Fe 3 O 4 core-shell NPs) are assembled into helical nanochain structures to be chiral-active. An in-house generator of h B -induced chiral NP assembly, that is, a plasmonic chirality enhancer (PCE), is newly fabricated to enhance the circular dichroism (CD) signals from chiral plasmonic interaction of the helical nanochain assembly with circularly polarized light, reaching a limit of detection (LOD) of 10 -10 M, a 1000-fold enhancement as compared to that of conventional CD spectrometry. These enhancements were successfully observed from enantiomeric molecules, oligomers, polymers, and drugs. Computational simulation studies also proved that total chiroptical properties of helical plasmonic chains could be readily changed by modifying the chiral structure of the analytes. The proposed PCE has the potential to be used as an advanced tool for qualitative and quantitative recognition of chiral materials, enabling further application in pharmaceutical and biomedical sensing and imaging.

The use of nanogels (NGs) to modulate surface-enhanced Raman scattering (SERS) activities is introduced as an innovative strategy to address certain critical issues with SERS-based immunoassays. This includes the chemical deformation of SERS nanotags, as well as their nonspecific interactions and effective "hotspots" formation. Herein, the polymeric cocoon and stimuli-responsive properties of NGs were used to encapsulate SERS nanotags containing plasmonic molybdenum trioxide quantum dots (MoO 3 -QDs). The pH-controlled release of the encapsulated nanotags and their subsequent localization by maleimide-functionalized magnetic nanoparticles facilitated the creation of "hotspots" regions with catalyzed SERS activities. This approach resulted in developing a biosensing platform for the ultrasensitive immunoassays of hepatitis E virus (HEV) or norovirus (NoV). The immunoassays were optimized using the corresponding virus-like particles to attain limits of detection of 6.5 and 8.2 fg/mL for HEV-LPs and NoV-LPs, respectively. The SERS-based technique achieved a signal enhancement factor of up to ∼10 8 due to the combined electromagnetic and chemical mechanisms of the employed dual-SERS substrate of MoO 3 -QDs/2D hexagonal boron nitride nanosheets. The highlight and validation of the developed SERS-based immunoassays was the detection of NoV in infected patients' fecal specimen and clinical HEV G7 subtype. Importantly, this system can be used to maintain the stability of SERS nanotags and improve their reliability in immunoassays.

Water splitting driven by renewable energy sources is considered a sustainable way of hydrogen production, an ideal fuel to overcome the energy issue and its environmental challenges. The rational design of electrocatalysts serves as a critical point to achieve efficient water splitting. Layered double hydroxides (LDHs) with two-dimensionally (2D) layered structures hold great potential in electrocatalysis owing to their ease of preparation, structural flexibility, and tenability. However, their application in catalysis is limited due to their low activity attributed to structural stacking with irrational electronic structures, and their sluggish mass transfers. To overcome this challenge, attempts have been made toward adjusting the morphological and electronic structure using appropriate design strategies. This review highlights the current progress made on design strategies of transition metal-based LDHs (TM-LDHs) and their application as novel catalysts for oxygen evolution reactions (OERs) in alkaline conditions. We describe various strategies employed to regulate the electronic structure and composition of TM-LDHs and we discuss their influence on OER performance. Finally, significant challenges and potential research directions are put forward to promote the possible future development of these novel TM-LDHs catalysts.

Hypothesis: Here, FePd magnetic nanoparticles (MNPs) are developed as artificial enzymes with high biocompatibility and reusability., Experiment: The nanoparticles (NPs) are synthesized in an aqueous solvent by one-pot synthesis utilizing glutathione (GSH) and cysteine (Cys) as surfactants., Findings: The prepared hydrophilic FePd NPs are redispersible in water. Further, they exhibit catalytic activity for the degradation of rhodamine B (RhB), as well as for the inhibition of reactive oxygen species (ROS) production induced by H 2 O 2 , which are two- and seven-fold enhancements of their catalytic performances, respectively, compared with that of horseradish peroxidase. The computational simulation and electrochemical analysis indicate that the enhancement of the catalytic effect is due to the protection of the MNP surface by GSH and Cys. In vitro experiments reveal that FePd MNPs behave like a peroxidase and decrease the ROS in mammalian cells. The cytotoxicity assessment of FePd MNPs via exposures to different cell lines for over seven days indicates that they can maintain the cell viability of >90% for up to 20 μgmL -1 concentration. FePd MNPs with high saturation magnetization and biocompatibility can be utilized as recyclable peroxidase-mimicking nanozymes and biosensors in a variety of catalytic and biological applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Lanthanide ion (Ln 3+ )-doped nanoscale hydroxyapatites (nHAp) with tunable luminescence have attracted increasing attention due to their potential applications as useful biomedical tools (e.g., imaging and clinical therapy). In this study, we reported that doping Terbium (III) ions (Tb 3+ ) in self-activated luminescent nHAp via a facile hydrothermal reaction, using trisodium citrate (Cit 3- ), generates unique emission-tunable probes known as Cit/Tb-nHAp. The morphology, crystal phase, and luminescence properties of these Cit/Tb-nHAp probes are studied in detail. Moreover, the results demonstrate that the luminescence of self-activated nHAp originates from the carbon dots trapped within the nHAp crystals, in which partial energy transfer occurs from carbon dots (CDs) to Tb 3+ . The color tunability is successfully achieved by regulating the addition of Cit 3- . Biocompatibility study indicates that when co-cultured with C6 glioma cells in vitro for 3 days, ≤800 ppm Cit/Tb-nHAp is not cytotoxic for C6 glioma cells. We also present in vitro data showing efficient cytoplasmic localization of transferrin conjugated Cit/Tb-nHAp into C6 glioma cells by fluorescence cell imaging. We have successfully engineered Cit/Tb-nHAp, a promising biocompatible agent for future in vitro and in vivo fluorescence bioimaging., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Whitlockite (WH; Ca 18 Mg 2 (HPO4) 2 (PO4) 12 ) is a calcium phosphate based ceramic that contains magnesium ions. As the second most abundant mineral in living bone, WH occupies 25-35 wt % of the inorganic portion of human bone. Compared to hydroxyapatite (HAp, Ca 10 (PO 4 ) 6 (OH) 2 ), WH possesses better mechanical properties, faster resorbability, and promotion behavior on the osteogenesis. In this article, we introduced a fabrication method of interconnected porous WH granules through vacuum filtration, followed by sintering treatment based on the thermal stability of WH synthesized using the tri-solvent system. This study presents a histological, radiological, and immunohistochemical evaluation of the bone healing potential of these WH granules in a 5 mm diameter calvarial bone defect in rats. The histological evaluation shows no inflammation or foreign body reaction in the WH group. The WH group displays newly formed bone at the same thickness as the original bone. On the contrary, bone formation is not observed in the nontreated (NT) group. Besides, immunohistochemistry (IHC) confirmed that WH granules promoted bone regeneration with the significantly higher expression of bone morphogenetic proteins-2 (BMP-2), alkaline phosphatase (ALP), osteopontin (OPN), and osteocalcin (OCN) compared to the NT group without the addition of exogenous cells or growth factors. These results suggest that WH has excellent potential for application in bone tissue regeneration.

Issues related to global energy and environment as well as health crisis are currently some of the greatest challenges faced by humanity, which compel us to develop new pollution-free and sustainable energy sources, as well as next-generation biodiagnostic solutions. Optical functional nanostructures that manipulate and confine light on a nanometer scale have recently emerged as leading candidates for a wide range of applications in solar energy conversion and biosensing. In this review, recent research progress in the development of photonic and plasmonic nanostructures for various applications in solar energy conversion, such as photovoltaics, photothermal conversion, and photocatalysis, is highlighted. Furthermore, the combination of photonic and plasmonic nanostructures for developing high-efficiency solar energy conversion systems is explored and discussed. We also discuss recent applications of photonic-plasmonic-based biosensors in the rapid management of infectious diseases at point-of-care as well as terahertz biosensing and imaging for improving global health. Finally, we discuss the current challenges and future prospects associated with the existing solar energy conversion and biosensing systems.

This study was performed to investigate the Eustachian tube as a potential route for contralateral spreading following intratympanic nanoparticle (NP)-conjugated gentamicin injection in a rat model. Sprague-Dawley rats were divided into three groups and substances were injected in the right ear: group 1 (fluorescent magnetic nanoparticles [F-MNPs], n = 4), group 2 (F-MNP-conjugated gentamicin [F-MNP@GM], n = 2), and control group (no injections, n = 2). T2-weighted sequences corresponding to the regions of interest at 1, 2, and 3 h after intratympanic injection were evaluated, along with immunostaining fluorescence of both side cochlea. The heterogeneous signal intensity of F-MNPs and F-MNP@GM on T2-weighted images, observed in the ipsilateral tympanum, was also detected in the contralateral tympanum in 4 out of 6 rats, recapitulating fluorescent nanoparticles in the contralateral cochlear hair cells. Computational simulations demonstrate the contralateral spreading of particles by gravity force following intratympanic injection in a rat model. The diffusion rate of the contralateral spreading relies on the sizes and surface charges of particles. Collectively, the Eustachian tube could be a route for contralateral spreading following intratympanic injection. Caution should be taken when using the contralateral ear as a control study investigating inner-ear drug delivery through the transtympanic approach.

Hexagonal boron nitride ( h -BN) has been considered a promising dielectric for two-dimensional (2D) material-based electronics due to its atomically smooth and charge-free interface with an in-plane lattice constant similar to that of graphene. Here, we report atomic layer deposition of boron nitride (ALD-BN) using BCl 3 and NH 3 precursors directly on thermal SiO 2 substrates at a relatively low temperature of 600 °C. The films were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and transmission electron microscopy wherein the uniform, atomically smooth, and nanocrystalline layered-BN thin film growth is observed. The growth rate is ∼0.042 nm/cycle at 600 °C, a temperature significantly lower than that of h -BN grown by chemical vapor deposition. The dielectric properties of the ALD-BN measured from Metal Oxide Semiconductor Capacitors are comparable with that of SiO 2 . Moreover, the ALD-BN exhibits a 2-fold increase in carrier mobility of graphene field effect transistors (G-FETs/ALD-BN/SiO 2 ) due to the lower surface charge density and inert surface of ALD-BN in comparison to that of G-FETs fabricated on bare SiO 2 . Therefore, this work suggests that the transfer-free deposition of ALD-BN on SiO 2 may be a promising candidate as a substrate for high performance graphene devices.

Multifunctional theranostic agents have recently attracted a great deal of attention in field of biomedicine. In the present work, folic acid-conjugated chitosan-functionalized graphene oxide (FA-CS-GO) has been developed as a new type of multifunctional nanomaterial for near-infrared fluorescence (FL)/photoacoustic imaging-(PAI) guided photothermal therapy (PTT) of cancer. In vitro results showed that the FA-CS-GO was able to completely destroy cancer cells under laser irradiation. More importantly, in vivo experiments showed that in the presence of targeted FA-CS-GO with laser irradiation, the tumors were completely inhibited, with no recurrence within 20 days. A high photoacoustic signal was detected in the tumor area of mice 24 h after the injection of FA-CS-GO, demonstrating the ability of FA-CS-GO to function as a new PAI contrast agent. Altogether, FA-CS-GO showed a high tumor-targeting efficiency, powerful photothermal effect, and outstanding PAI. This study is considered the first where multifunctional nanomaterials were used for highly efficient FL/PAI-guided tumor-targeted PTT, which is a promising avenue for theranostic nanomedicine., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2019. Published by Elsevier B.V.)

The astrophysical phenomenon of mimetic helical magnetic field ( h B )-assisted self-assembly is herein introduced to build helical superstructures that display chiroptical properties. As a building block, magnetoplasmonic (MagPlas) Ag@Fe 3 O 4 core-shell nanoparticles are used to guide plasmonic Ag nanoparticles onto a helical magnetic flux. The chirality of the assembled helical structures and tailored circular dichroism are successfully tuned in real time, and the handedness of the assembled structures is dynamically switched by the h B at the millisecond level, which is at least 6000-fold faster than other template-assisted methods. The peak position of circular dichroism can be reconfigured by altering the plasmonic resonance or coupling by controlling the size of the Ag core and magnetic flux density. The h B -induced chirality modulation represents a method to control the polarization state of light at the nexus of plasmonics, magnetic self-assembly, colloidal science, liquid crystals, and chirality. It presents active and dynamic chiral assemblies of magnetoplasmonic nanomaterials, enabling further practical applications in optical devices.

Whitlockite (WH, Ca 18 Mg 2 (HPO 4 ) 2 (PO 4 ) 12 ) is the second most abundant bone mineral and has attracted attention as one of the novel bone regenerative materials. It has proven to enhance growth and promote osteogenesis of stem cells. However, investigating the mechanism of formation of pure phase WH nanocrystals remains a challenge. In this study, we introduced an interesting synthesis approach of WH nanocrystals using a tri-solvent system for the solid-liquid-solution (SLS) process. The ratio of precursor and reaction solvent composition was optimized to generate WH nanocrystals with tunable size, morphology (nanoplates, nanospheres), and surface properties (hydrophobic, hydrophilic), which is impossible to achieve using the traditional precipitation method. Molecular dynamics (MD) simulations revealed that the growth direction of nanoplates is highly related to the surfactant and its binding affinity. Finite element method (FEM) simulations elucidated that the ratio of ethanol/water plays an important role in defining the crystallinity and morphology of WH. In this study, we demonstrated that the cell proliferation of human bone marrow-derived mesenchymal stem cells (hBMSCs) is enhanced upon treatment with WH. The results of quantitative real-time polymerase chain reaction (qPCR) revealed that WH can positively accelerate the osteogenic differentiation in hBMSCs. The as-synthesized WH has a great potential in the future to be used in osteogenic tissue engineering. This study opens a new horizon for the synthesis and application of WH., (Copyright © 2020 Elsevier Inc. All rights reserved.)

From senescence and frailty that may result from various biological, mechanical, nutritional, and metabolic processes, the human body has its own antioxidant defense enzymes to remove by-products of oxygen metabolism, and if unregulated, can cause several types of cell damage. Herein, an antioxidant, artificial nanoscale enzyme, called nanozyme (NZs), is introduced that is composed of Au nanoparticles (NPs) synthesized with a mixture of two representative phytochemicals, namely, gallic acid (GA) and isoflavone (IF), referred to as GI-Au NZs. Their unique antioxidant and anti-aging effects are monitored using Cell Counting Kit-8 and senescence-associated β-galactosidase assays on neonatal human dermal fibroblasts (nHDFs). Furthermore, alterations in epidermal thickness and SOD activity are measured under ultraviolet light to investigate the effects of the topical application of NZs on the histological structure and antioxidant activity in hairless mice skin. Then, hepatotoxicity and nephrotoxicity in the hairless mice are monitored. It is concluded that the NZs can effectively prevent serial passage-induced senescence in nHDFs, as well as oxidative stress in mice skin, suggesting a range of strategies to further develop novel therapeutics for acute frailty., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Control of the chemical and physical properties of nanoscale colloids and their nanoassemblies remains a challenging issue for enhancing the performance and functionalities of nanodevices. In this study, we report a post-synthesis etching method to tailor the porosity of the Fe 3 O 4 shells coating on Ag NPs, establishing a facile but effective approach to regulate the chemical and optical properties of the colloids and their assembled structures. As the shell porosity increases, the NPs are transformed, producing enhanced catalytic activity and the surface-enhanced Raman spectroscopy (SERS) effect, which results from enhanced chemical diffusion into the Ag core. Magnetoplasmonic (MagPlas) one- (1D) and two- (2D) dimensional arrays fabricated using these porosity-controllable NPs exhibit intriguing plasmon properties that are strongly affected by the porosity of the particle shell. Furthermore, the bright coloration of the 2D arrays is tuned by changing the shell porosity or introducing an additional metallic layer. Such 1D and 2D porous MagPlas metastructures possessing Fe 3 O 4 shells with tunable porosities are a fulcrum for developing recyclable catalysts and tunable optical filters with optimized activity, selectivity, and sensitivity, as well as color displays and sensing platforms.

One-dimensional nanostructures with controllable aspect ratios are essential for a wide range of applications. An approach for magnetic superparticle (SP) assembly over large areas (55 mm × 25 mm) is introduced via co-assistance of electrostatic and magnetic fields, so-called magnetic layer-by-layer assembly, on an arbitrary hydrophilic substrate within minutes. The SP structures [diameter ( d ) = 120-350 nm] of Fe 3 O 4 or Ag@Fe 3 O 4 composites composed of hundreds of magnetite nanocrystals ( d = 10-20 nm) are used as colloidal monomers to fabricate arrays of high aspect ratio (up to 10 2 ) linear nanochains, viz . colloidal polymers, where thermal disturbances were minimized. The arrays of colloidal polymers exhibit strong optical polarization effects owing to their geometrical anisotropy, which can be used as a simple optical filter. Furthermore, by using the binary colloidal mixture of different magnetic colloids, including different sized Fe 3 O 4 and magnetoplasmonic Ag@Fe 3 O 4 , low aspect ratio (2-15) colloidal chains, viz . magnetic/plasmonic oligomers, with tunable lengths were fabricated, affording a facile but an effective approach to modulate the optical properties of the chains. The scalable fabrication of well-aligned, linear colloidal polymers and oligomers opens up appealing opportunities for the development of sensors, subwavelength waveguides, optical tweezers, and enhanced solar harvesting devices.

We prepared ZnO nanocomposites with WO 3 or CuO nanostructures to improve the photocatalytic performance of ZnO nanostructures. Characterization of the nanocomposites using scanning electron microscopy, x-ray diffraction, UV-vis spectrometry and photoluminescence revealed the morphologies and wide light absorption range of the materials. The highest current densities of WO 3 /ZnO and CuO/ZnO nanocomposites were 1.28 mA cm -2 and 2.49 mA cm -2 at 1.23 V (versus a reversible hydrogen electrode) under AM 1.5 100 mW cm -2 , which are ~1.2- and 3.5-fold greater than those of bare ZnO nanostructures, respectively. The easy fabrication process suggests that nanocomposites with narrow bandgap materials, such as WO 3 and CuO, will improve the performance of electrochemical and optoelectrical devices such as dye-sensitized solar cells and biosensors.