Core-shell Nanohybrid Research Articles

Prussian blue-decorated indocyanine green-loaded mesoporous silica nanohybrid for synergistic photothermal-photodynamic-chemodynamic therapy against methicillin-resistant Staphylococcus aureus

Nanomaterial-based synergistic antibacterial agents are considered as promising tools to combat infections caused by antibiotic-resistant bacteria. Herein, multifunctional mesoporous silica nanoparticle (MSN)-based nanocomposites were fabricated for synergistic photothermal/photodynamic/chemodynamic therapy against methicillin-resistant Staphylococcus aureus (MRSA). MSN loaded with indocyanine green (ICG) as a core, while Prussian blue (PB) nanostructure was decorated on MSN surface via in situ growth method to form a core-shell nanohybrid (MSN-ICG@PB). Upon a near infrared (NIR) laser excitation, MSN-ICG@PB (200 μg mL−1) exhibited highly efficient singlet oxygen (1O2) generation and hyperthermia effect (48.7℃). In the presence of exogenous H2O2, PB with peroxidase-like activity promoted the generation of toxic hydroxyl radicals (•OH) to achieve chemodynamic therapy (CDT). PTT can greatly increase the permeability of bacterial lipid membrane, facilitating the generated 1O2 and •OH to kill bacteria more efficiently. Under NIR irradiation and exogenous H2O2, MSN-ICG@PB (200 μg mL−1) with good biocompatibility exhibited a synergistic antibacterial effect against MRSA with high bacterial killing efficiency (>98 %). Moreover, due to the synergistic bactericidal mechanism, MSN-ICG@PB with satisfactory biosafety makes it a promising antimicrobial agent to fight against MRSA.

Galvanic Replacement Synthesis of VOx@EGaIn-PEG Core-Shell Nanohybrids for Peroxidase Mimics.

The development of high-performance biosensors is a key focus in the nanozyme field, but the current limitations in biocompatibility and recyclability hinder their broader applications. Herein, we address these challenges by constructing core-shell nanohybrids with biocompatible poly(ethylene glycol) (PEG) modification using a galvanic replacement reaction between orthovanadate ions and liquid metal (LM) (VOx@EGaIn-PEG). By leveraging the excellent charge transfer properties and the low band gap of the LM surface oxide, the VOx@EGaIn-PEG heterojunction can effectively convert hydrogen peroxide into hydroxyl radicals, demonstrating excellent peroxidase-like activity and stability (Km = 490 μM, vmax = 1.206 μM/s). The unique self-healing characteristics of LM further enable the recovery and regeneration of VOx@EGaIn-PEG nanozymes, thereby significantly reducing the cost of biological detection. Building upon this, we developed a nanozyme colorimetric sensor suitable for biological systems and integrated it with a smartphone to create an efficient quantitative detection platform. This platform allows for the convenient and sensitive detection of glucose in serum samples, exhibiting a good linear relationship in the range of 10-500 μM and a detection limit of 2.35 μM. The remarkable catalytic potential of LM, combined with its biocompatibility and regenerative properties, offers valuable insights for applications in catalysis and biomedical fields.

Catechol-formaldehyde resin microspheres@UiO-66-NH2@ CdS core-shell nanohybrids as robust visible-light photocatalyst for multifunctional applications

Well-defined zirconium based metal-organic frameworks (MOFs) coated polymer core-shell nanohybrid (CFR@MOF) was constructed using catechol formaldehyde resin (CFR) microspheres as a support, followed by encapsulating CdS nanoparticles (NPs) into MOF (UiO-66-NH2) shell layers to obtain CFR@UiO-66-NH2@CdS nanohybrids to enhance visible photosensitization for multifunctional photocatalytic applications including organic pollutant degradation, water disinfection and photoinduced atomic transfer radical polymerization (photoATRP). The CFR microspheres with a regular spherical morphology (200–400 nm) provided a versatile initial platform for the growth of MOF shells through mononuclear coating. The impact of different loadings of CdS NPs incorporated into CFR@UiO-66-NH2 shells on photocatalytic performance was systematically investigated. CFR@UiO-66-NH2 @CdS demonstrated robust dye degradation and antibacterial ability. Especially, a remarkable inhibitory efficiency of 99.99 % and 99.7 % was achieved for S. aureus and E. coli, with a low photocatalyst dosage (100 μg/mL) under visible light. Furthermore, by combining CFR@UiO-66-NH2@CdS with CuBr2/L catalysts, a high-efficiency red-light triggered photoredox catalytic polymerization system was established in photoinduced atom transfer radical polymerization (photoATRP), achieving high conversion rate (>90 %) for various monomers in a short time.

A facile dual-mode immunosensor based on speckle Ag-doped nanohybrids for ultrasensitive detection of Ochratoxin A

Ochratoxin A (OTA) is a potent carcinogen, and is among the most dangerous mycotoxins in agricultural products. In this study, an ultrasensitive dual-mode immunosensor was developed for naked-eye and fluorescence detection of OTA based on Ag-doped core–shell nanohybrids (Ag@CSNH). Complete antigen-labeled Ag@CSNH (CA-Ag@CSNH) were used as a competitive bind and dual-mode probe. The diffused doping structure of CA-Ag@CSNH provided improved stability, color and fluorescence quencher performance. Antibodies modified magnetic beads were used as a capture probe. The competitive binding between OTA and CA-Ag@CSNH produced both color change and fluorescence quenching. Ultraviolet and fluorescence intensitie correlated linearly with OTA concentration ranges of 0.03–3 ng/mL and 10–10000 pg/mL, and limits of detection of 0.0235 ng/mL and 0.9921 pg/mL, respectively. The practical applicability of proposed strategy was demonstrated by analysis of OTA in spiked corn, soybean and flour samples. This study offers a new insight on multi-mode platforms for various applications.

Magnetic UiO-66-NH2 Core-Shell Nanohybrid as a Promising Carrier for Quercetin Targeted Delivery toward Human Breast Cancer Cells.

In this study, a magnetic core-shell metal-organic framework (MOF) nanocomposite, Fe3O4-COOH@UiO-66-NH2, was synthesized for tumor-targeting drug delivery by incorporating carboxylate groups as functional groups onto ferrite nanoparticle surfaces, followed by fabrication of the UiO-66-NH2 shell using a facile self-assembly approach. The anticancer drug quercetin (QU) was loaded into the magnetic core-shell nanoparticles. The synthesized magnetic nanoparticles were comprehensively evaluated through multiple techniques, including FT-IR, PXRD, FE-SEM, TEM, EDX, BET, UV-vis, ZP, and VSM. Drug release investigations were conducted to investigate the release behavior of QU from the nanocomposite at two different pH values (7.4 and 5.4). The results revealed that QU@Fe3O4-COOH@UiO-66-NH2 exhibited a high loading capacity of 43.1% and pH-dependent release behavior, maintaining sustained release characteristics over a prolonged duration of 11 days. Furthermore, cytotoxicity assays using the human breast cancer cell line MDA-MB-231 and the normal cell line HEK-293 were performed to evaluate the cytotoxic effects of QU, UiO-66-NH2, Fe3O4-COOH, Fe3O4-COOH@UiO-66-NH2, and QU@Fe3O4-COOH@UiO-66-NH2. Treatment with QU@Fe3O4-COOH@UiO-66-NH2 substantially reduced the cell viability in cancerous MDA-MB-231 cells. Cellular uptake and cell death mechanisms were further investigated, demonstrating the internalization of QU@Fe3O4-COOH@UiO-66-NH2 by cancer cells and the induction of cancer cell death through the apoptosis pathway. These findings highlight the considerable potential of Fe3O4-COOH@UiO-66-NH2 as a targeted nanocarrier for the delivery of anticancer drugs.

Hydrothermal synthesis of antibacterial silver@cuprous oxide core-shell/hydroxyapatite (Ag@Cu2O/HAp) hetero-nanohybrids

ABSTRACT In the present work, we examined the antibacterial activity of novel silver@cuprous oxide core-shell/hydroxyapatite (Ag@Cu2O/HAp) hetero-nanohybrids against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. The hydrothermal technique was used to easily synthesise Ag@Cu2O/HAp core-shell nanohybrid structures. Immobilisation of Ag@Cu2O core shells on HAp nanoparticles was done by controlling the relative concentrations of Ag, Cu2O, and HAp. The Ag@Cu2O/HAp nanohybrids were characterised using XRD, FTIR, Raman, UV-vis, SEM, EDX, TEM, and SAED methods. By observing the growth of S. aureus and E. coli populations in the presence and absence of Ag, Ag@Cu2O, HAp, and Ag@Cu2O/HAp nanoparticles, their antibacterial impact was compared. MIC Alamar Blue assay was performed to study the cytotoxicity of Ag@Cu2O/HAp nanomaterials. In addition, reactive oxygen species (ROS) studies were conducted to understand the type of active species produced under light and dark conditions. The possible photochemical and antibacterial mechanisms of the Ag@Cu2O/HAp nanohybrids against S. aureus and E. coli bacteria were proposed. In addition, the promising antibacterial nature of Ag@Cu2O/HAp materials suggests that they are good candidates for industrial and biomedical applications.

Interfacial Compatibility of Core-Shell Cellulose Nanocrystals for Improving Dynamic Covalent Adaptable Networks' Fracture Resistance in Nanohybrid Vitrimer Composites.

The development of polymeric nanocomposites with dynamic covalent adaptable networks and biobased nanomaterials has been a promising approach toward sustainable advanced materials, enabling reprogramming and recycling capabilities. Herein, a core-shell nanohybrid of functionalized cellulose nanocrystals (CNCs) is explored to provide crucial interfacial compatibility for improving the covalent adaptable networks of epoxy-thiol vitrimers in fracture resistance. The poly(ε-caprolactone) (PCL) shells grafted from CNC surfaces can be cross-linked with the covalent adaptable networks via a hot-pressing transesterification process. According to the additive concentration and annealing temperature, the stress relaxation behavior of nanohybrid vitrimer composites can be effectively regulated by the core-shell PCL-grafted CNC (CNC-PCL) nanohybrids from a dispersed to cross-linked interaction. The addition of 15 wt % of the core-shell CNC-PCLs exhibits the reinforced improvement of nanohybrid vitrimer composites in the average Young's modulus of 2.5×, fracture stress of 5.4×, and fracture strain of 2.0×. The research findings might have profound implications for developing synergistic interfacial compatibility between dynamic vitrimer networks and functional nanoparticles for advanced polymeric nanocomposites.

Constructing epoxy and imidazole dual-functionalized polyurethane@Zinc oxide core-shell crosslinker based on coordination interactions for the preparation of strong, tough, and water-resistant soybean flour adhesives

Nanofilling has been regarded as an effective strategy to enhance adhesion performances of soybean flour (SF) adhesives, while it still exists huge challenges to regulate the interfacial properties of nanocomposites toward strong, tough, and water-resistant system. Here, we report on engineering interfacial crosslinking of nanohybrid and SF matrix via core–shell structure design. The reactive core–shell nanohybrid is prepared by epoxy and imidazole dual-functionalized polyurethane shell and zinc oxide (ZnO) nanofiller core under deposition effect of interfacial coordination interactions. Combining reactive epoxy groups and dynamic imidazole/ZnO bonds, a high-performance crosslinking structure with energy dissipation mechanism has been constructed at the interface of ZnO and SF matrix. The structure not only improves the stability of SF adhesive network to resist the external destruction of stress and moisture but also provides dynamic imidazole/metal cation coordination bonds as sacrificial units to facilitate energy dissipation during loading. Results show that the adhesives modified by 5 wt% core–shell nanohybrid present the best performances, in which an 142.0%, 162.3%, and 283.6% increment are observed in dry adhesion strength, wet adhesion strength, and adhesion toughness compared to pristine SF adhesives. Overall, such a high-performance biomass-derived adhesive has great potential for the practical use in wood industry.

Liquid‐Metal‐Assisted Programmed Galvanic Engineering of Core–shell Nanohybrids for Microwave Absorption

AbstractCore–shell nanostructures have received widespread attention because of their potential usage in various technological and scientific fields. However, they still face significant challenges in terms of fabrication of core–shell nanostructure libraries on a controlled, and even programmed scale. This study proposes a general approach to systematically fabricate core–shell nanohybrids using liquid‐metal Ga alloys as reconfigurable templates, and the initiation of a local galvanic replacement reaction is demonstrated utilizing an ultrasonic system. Under ultrasonic agitation, the hydrated gallium oxides generated on the liquid metal droplets, simultaneously delaminated themselves from the interfaces. Subsequently, single‐metal or bimetallic components are deposited on fresh smooth Ga‐based alloys via galvanic reactions to form unique core–shell metal/metal nanohybrids. Controlled and quantitative regulation of the diversity of the non‐homogeneous nanoparticle shell layer composition is achieved. The obtained core–shell nanostructures are used as efficient microwave absorbers to dissipate unwanted electromagnetic wave pollution. The effective absorption bands (90% absorption) of core–shell GaNi and GaCoNi nanohybrids are 3.92 and 3.8 GHz at a thickness of 1.4 mm, respectively. This general and advanced strategy enables the growth of other oxides or sulfides by spontaneous interfacial redox reactions for the fabrication of functional materials in the future.

Fast and convenient delivery of fluidextracts liquorice through electrospun core-shell nanohybrids.

Introduction: As an interdisciplinary field, drug delivery relies on the developments of modern science and technology. Correspondingly, how to upgrade the traditional dosage forms for a more efficacious, safer, and convenient drug delivery poses a continuous challenge to researchers. Methods, results and discussion: In this study, a proof-of-concept demonstration was conducted to convert a popular traditional liquid dosage form (a commercial oral compound solution prepared from an intermediate licorice fluidextract) into a solid dosage form. The oral commercial solution was successfully encapsulated into the core-shell nanohybrids, and the ethanol in the oral solution was removed. The SEM and TEM evaluations showed that the prepared nanofibers had linear morphologies without any discerned spindles or beads and an obvious core-shell nanostructure. The FTIR and XRD results verified that the active ingredients in the commercial solution were compatible with the polymeric matrices and were presented in the core section in an amorphous state. Three different types of methods were developed, and the fast dissolution of the electrospun core-shell nanofibers was verified. Conclusion: Coaxial electrospinning can act as a nano pharmaceutical technique to upgrade the traditional oral solution into fast-dissolving solid drug delivery films to retain the advantages of the liquid dosage forms and the solid dosage forms.

In-situ fabrication of novel Au nanoclusters-Cu2+@sodium alginate/hyaluronic acid nanohybrid gels for cuproptosis enhanced photothermal/photodynamic/chemodynamic therapy via tumor microenvironment regulation

Multimodal combined therapy (MCT) is an emerging avenue to eliminate tumor cells by the synergistic effect of various therapeutic methods. However, the complex tumor microenvironment (TME) is becoming the key barrier to the therapeutic effect of MCT due to the excessive existence of H+ ions, H2O2, and glutathione (GSH), the lack of O2, and the relaxation of ferroptosis. To overcome these limitations, smart nanohybrid gels with excellent biocompatibility, stability and targeting function were prepared by using gold nanoclusters as cores and an in situ cross-linking composite gel of sodium alginate (SA)/hyaluronic acid (HA) as the shell. The obtained Au NCs-Cu2+@SA-HA core–shell nanohybrid gels possessed near-infrared light response synergistically benefitting photothermal imaging guided photothermal therapy (PTT) and photodynamic therapy (PDT). Meanwhile, the H+-triggered release of Cu2+ ions from the nanohybrid gels not only induces cuproptosis to avoid the relaxation of ferroptosis, but also catalyzes H2O2 in the TME to generate O2 to simultaneously improve the hypoxic microenvironment and PDT effect. Furthermore, the released Cu2+ ions could consume the excessive GSH to form Cu+ ions effectively, which caused the formation of hydroxyl free radicals (·OH) to kill tumor cells, synergistically realizing GSH consumption-enhanced PDT and chemodynamic therapy (CDT). Hence, the novel design in our work provides another research avenue for cuproptosis-enhanced PTT/PDT/CDT via TME modulation.

Sequential Delivery of Novel Triple Drug Combination via Crosslinked Alginate/Lactoferrin Nanohybrids for Enhanced Breast Cancer Treatment.

While breast cancer remains a global health concern, the elaboration of rationally designed drug combinations coupled with advanced biocompatible delivery systems offers new promising treatment venues. Herein, we repurposed rosuvastatin (RST) based on its selective tumor apoptotic effect and combined it with the antimetabolite pemetrexed (PMT) and the tumor-sensitizing polyphenol honokiol (HK). This synergistic three-drug combination was incorporated into protein polysaccharide nanohybrids fabricated by utilizing sodium alginate (ALG) and lactoferrin (LF), inspired by the stealth property of the former and the cancer cell targeting capability of the latter. ALG was conjugated to PMT and then coupled with LF which was conjugated to RST, forming core shell nanohybrids into which HK was physically loaded, followed by cross linking using genipin. The crosslinked HK-loaded PMT-ALG/LF-RST nanohybrids exhibited a fair drug loading of 7.86, 5.24 and 6.11% for RST, PMT and HK, respectively. It demonstrated an eight-fold decrease in the IC50 compared to the free drug combination, in addition to showing an enhanced cellular uptake by MCF-7 cells. The in vivo antitumor efficacy in a breast cancer-bearing mouse model confirmed the superiority of the triple cocktail-loaded nanohybrids. Conclusively, our rationally designed triple drug-loaded protein/polysaccharide nanohybrids offer a promising, biocompatible approach for an effective breast tumor suppression.

Optimization of H2O2 production in a small-scale off-grid buffer layer flow cell equipped with Cobalt@N-doped graphitic carbon core–shell nanohybrid electrocatalyst

Electrochemical oxygen reduction (ORR) to hydrogen peroxide (H2O2) is emerging as a sustainable approach for the production of ‘green’ H2O2 requiring only oxygen and electricity compared to the energy intensive anthraquinone process. High 2e− selectivity is required in order to boost faradaic and energy efficiency (FE) of the process. Upon correct tuning of their properties, nitrogen-doped carbon materials are excellent candidates as electrocatalyst for H2O2 electrosynthesis due to their chemical and electrochemical resistance and 2e− selectivity. Furthermore, careful cell design and parameter optimization are mandatory for an industrial scale up of the process. In this study, a Cobalt@N-doped graphitic carbon core–shell nanohybrid (CS(Co)-N-GC) electrocatalyst was studied in a buffer layer complete cell equipped with a proton exchange membrane in order to determine the effect of flow rate and potential on process selectivity and energy efficiency. After optimization, the cell was able to produce 0.5 wt% H2O2 with an average FE higher than 40%, an energy consumption lower than 8 kWh/kgH2O2 and a production rate of 1.2 g/h gcat @ 0.3 V vs RHE with the possibility to produce up to 1 wt% H2O2.

Electrospun Core (HPMC-Acetaminophen)-Shell (PVP-Sucralose) Nanohybrids for Rapid Drug Delivery.

The gels of cellulose and its derivatives have a broad and deep application in pharmaceutics; however, limited attention has been paid to the influences of other additives on the gelation processes and their functional performances. In this study, a new type of electrospun core–shell nanohybrid was fabricated using modified, coaxial electrospinning which contained composites of hydroxypropyl methyl cellulose (HPMC) and acetaminophen (AAP) in the core sections and composites of PVP and sucralose in the shell sections. A series of characterizations demonstrated that the core–shell hybrids had linear morphology with clear core–shell nanostructures, and AAP and sucralose distributed in the core and shell section in an amorphous state separately due to favorable secondary interactions such as hydrogen bonding. Compared with the electrospun HPMC–AAP nanocomposites from single-fluid electrospinning of the core fluid, the core–shell nanohybrids were able to promote the water absorbance and HMPC gelation formation processes, which, in turn, ensured a faster release of AAP for potential orodispersible drug delivery applications. The mechanisms of the drug released from these nanofibers were demonstrated to be a combination of erosion and diffusion mechanisms. The presented protocols pave a way to adjust the properties of electrospun, cellulose-based, fibrous gels for better functional applications.

Gold@Carbon Nitride Yolk and Core-Shell Nanohybrids.

Graphitic carbon nitride (g-C3N4) is a promising conjugated polymer with visible light responsiveness and numerous intriguing characteristics that make it highly beneficial for a myriad of potential applications. A novel design and universal approach for the fabrication of unique plasmonic g-C3N4 nanoscale hybrids, with well-controlled morphology, is presented. A single gold nanoprism is encapsulated within dense or hollow g-C3N4 spheres for the formation of Au@g-C3N4 core-shell and Au@g-C3N4 yolk-shell nanohybrids. Au nanoprisms were chosen duo to the strong (visible range) plasmon resonances and electromagnetic field hotspots formed at their sharp corners. The incorporation of Au nanoprisms into the g-C3N4 nanospheres results in a dramatic ∼threefold rise in the emission of plasmonic g-C3N4 yolk-shell nanohybrids and ∼3.6-fold enhancement of the photocurrent density obtained from the plasmonic g-C3N4 core-shell nanohybrids, when compared with the g-C3N4 hollow nanospheres. Hence, these hybrids can potentially benefit applications in the areas spanning from solar energy harvesting to biomedical imaging and theranostics.

The bonding strength, water resistance and flame retardancy of soy protein-based adhesive by incorporating tailor-made core–shell nanohybrid compounds

A weak bonding strength and poor water resistance of soy protein-based adhesives have limited their application as a bio-based non-formaldehyde adhesive in the wood manufacturing industry. In this work, a soy protein-based adhesive was developed by incorporating tailor-made core–shell hybrids, which were synthesized by co-deposition of biomass Tannic acid (TA) as “hard cores” and silanized phenylphosphodichloride (BPOD(Si)) as “flexible shells”. For the soy protein-based adhesive system, the incorporated hybrids were designed as reinforcing elements and crosslinker to construct multiple crosslinked networks, which are beneficial to improve the bonding strength, water resistance and flame retardancy of the final adhesive. For example, the particleboards could be made by mixing with soy protein-based adhesives which show a rupture modulus of 15 MPa, an elasticity modulus of close to 2000 MPa and an internal bonding strength of 0.44 MPa, an increase of 110%, 110% and 145% respectively were registered when comparing with those of pristine soy protein-based adhesive. In addition, the soy protein-based adhesive was also designed to be potentially applied in furniture particleboard manufacturing area, and the flame retardancy could be achieved by a synergistic effect of denaturant borax and flame retardant in hybrids. Consequently, the soy protein-based adhesive showed a Limited oxygen index (LOI) value of 28.7% and the V-1 rating in UL-94 test. Therefore, this work provides a feasible method to produce non-formaldehyde and multifunctional soy protein-based adhesives.

An Iron Shield to Protect Epigallocatehin-3-Gallate from Degradation: Multifunctional Self-Assembled Iron Oxide Nanocarrier Enhances Protein Kinase CK2 Intracellular Targeting and Inhibition.

Protein kinase CK2 is largely involved in cell proliferation and apoptosis and is generally recognized as an Achilles’ heel of cancer, being overexpressed in several malignancies. The beneficial effects of (−)-epigallocatechin-3-gallate (EGCG) in the prevention and treatment of several diseases, including cancer, have been widely reported. However, poor stability and limited bioavailability hinder the development of EGCG as an effective therapeutic agent. The combination of innovative nanomaterials and bioactive compounds into nanoparticle-based systems demonstrates the synergistic advantages of nanocomplexes as compared to the individual components. In the present study, we developed a self-assembled core-shell nanohybrid (SAMN@EGCG) combining EGCG and intrinsic dual-signal iron oxide nanoparticles (Surface Active Maghemite Nanoparticles). Interestingly, nano-immobilization on SAMNs protects EGCG from degradation, preventing its auto-oxidation. Most importantly, the nanohybrid was able to successfully deliver EGCG into cancer cells, displaying impressive protein kinase CK2 inhibition comparable to that obtained with the most specific CK2 inhibitor, CX-4945 (5.5 vs. 3 µM), thus promoting the phytochemical exploitation as a valuable alternative for cancer therapy. Finally, to assess the advantages offered by nano-immobilization, we tested SAMN@EGCG against Pseudomonas aeruginosa, a Gram-negative bacterium involved in severe lung infections. An improved antimicrobial effect with a drastic drop of MIC from 500 to 32.7 μM was shown.

Multifunctional boronic acid-functionalized magnetic nanohybrid: An efficient and selective adsorbent of cis-diol-flavonoids

A novel magnetically and efficiently multifunctional boronic acid (BA) -functionalized core-shell nanohybrid (Fe3O4@SiO2@BA) was prepared for capture and separation of cis-diol-flavonoids. The morphology and physicochemical properties of resultant nanoparticles were systematically characterized via several techniques, and the results confirmed that the target nanohybrids were successfully functionalized and modified. Meanwhile, two flavonoids (quercetin and luteolin) were selected to investigate the selective capture of the Fe3O4@SiO2@BA in procedure of magnetic solid phase extraction (MSPE). The main parameters influencing the adsorption and elution conditions were systematically investigated and optimized. Furthermore, the adsorption kinetic models were adopted to elucidate the adsorption process, indicating that the pseudo-second-order model was suitable to explain the adsorption kinetics. Under the optimum conditions, the MSPE-HPLC-MS/MS approach was established with a wide linear dynamic range and good linearity (R2 ​> ​0.999), low limits of detection (0.0096–0.033 ​μg ​L−1) and satisfactory recoveries (91–107.6%). The proposed analytical method was successfully applicated by determining the content of target flavonoids in food samples (apple and onion). Accordingly, the prepared nanohybrid could serve as an efficient, rapid and economical potential adsorbent for extracting cis-diol-flavonoids in complex food samples.

Fe0.8Zn0.2 Nanoparticles Wrapped in Mesoporous Nitrogen-Doped Carbon Layers as Electrocatalysts for an Efficient Oxygen Reduction Reaction

An efficient oxygen reduction reaction (ORR) can be achieved by accelerating the movement of electrons, ions, reactants, and products. Here, we prepared core–shell nanohybrids with Fe0.8Zn0.2 nanop...

Accurately Regulating the Electronic Structure of Nix Sey @NC Core-Shell Nanohybrids through Controllable Selenization of a Ni-MOF for pH-Universal Hydrogen Evolution Reaction.

N-doped carbon-encapsulated transition metal selenides (TMSs) have garnered increasing attention as promising electrocatalysts for hydrogen evolution reaction (HER). Accurately regulating the electronic structure of these nanohybrids to reveal the underlying mechanism for enhanced HER performances is still challenging and thus requires deep excavation. Herein, a series of pomegranate-like Nix Sey @NC core-shell nanohybrids (including Ni0.85 Se @ NC, NiSe2 @NC, and NiSe@NC) through controllable selenization of a Ni-MOF precursor is reported. The component of the nanohybrids can be fine-tuned by tailoring the selenization temperature and feed ratio, through which the electronic structure can be synchronously regulated. Among these nanohybrids, the Ni0.85 Se @ NC exhibits the optimum pH-universal HER performance with overpotentials of 131, 135, and 183mV in 0.5 m H2 SO4 , 1.0 m KOH, and 1.0 m PBS, respectively, at 10 mA cm-2 , which are attributed to the increased partial density of state at the Fermi level and effective van der Waals interactions between Ni0.85 Se and NC matrix explained by density functional theory calculations.