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Surface-enhanced Raman scattering (SERS) has emerged as a valuable technique for molecular identification. Due to the characteristics of high sensitivity, excellent signal specificity, and photobleaching resistance, SERS has been widely used in the fields of environmental monitoring, food safety, and disease diagnosis. By attaching the organic molecules to the surface of plasmonic nanoparticles, the obtained SERS tags show high-performance multiplexing capability for biosensing. The past decade has witnessed the progress of SERS tags for liquid biopsy, bioimaging, and theranostics applications. This review focuses on the advances of SERS tags in biomedical fields. We first introduce the building blocks of SERS tags, followed by the summarization of recent progress in SERS tags employed for detecting biomarkers, such as DNA, miRNA, and protein in biological fluids, as well as imaging from

Conversion anode materials such as Mn3O4 draw much attention due to their considerable theoretical capacity for lithium-ion batteries (LIBs). However, poor conductivity, slow solid-state Li-ion diffusion, and huge volume expansion of the active materials during charge/discharge lead to unsatisfied electrochemical performance. Despite several strategies like nanocrystallization, fabricating hierarchical nanostructures, and introducing a matrix are valid to address these crucial issues, the achieved electrochemical performance still needs to be further enhanced. What is worse, the matrix with less or no Li-ion storage activity may lower the achieved capacity of the electrodes. Herein, ultra-thin CuMnO2 nanosheets with the thickness of 5–8 nm were evaluated for LIBs. The ultra-thin sheet-like nanostructure offers sufficient contact areas with electrolyte and shortens the Li-ion diffusion distance. Moreover, the in-situ generated Mn and Cu along with their oxides could play the role of matrix and conductive agent in turn at different stages, relieving the stress brought by volume expansion. Therefore, the as-prepared ultra-thin CuMnO2 nanosheets electrode displays a remarkable reversible capacity, long cycling stability, and outstanding rate capability (a reversible capacity of 1160.5 mAh g−1 at 0.1A g−1 was retained after 100 cycles with a capacity retention of 95.1 %, and 717.8 mAh g−1 at 2.0 A g−1 after 400 cycles).

Layered metal sulfides are considered as promising candidates for potassium ion batteries (KIBs) owing to the unique interlayer passages for ion diffusion. However, the insufficient electronic conductivity, inevitable volume expansion, and sulfur loss hinder the promotion of K-ion storage performance. Herein, few-layered Ti3C2Tx nanosheets were selected as the multi-functional substrate for cooperating few-layered SnS2 nanosheets, constructing SnS2/Ti3C2Tx hetero-structural nanosheets (HNs) with the thickness as thin as about 5 nm. In this configuration, the formed Ti-S bonds provide robust interaction between SnS2 and Ti3C2Tx nanosheets, which hinders the agglomeration of SnS2 and the restack of Ti3C2Tx, endowing the hybrid material with robust nanostructure. Thus, the shortcomings of the SnS2 anode are muchly relieved. In this way, the as-prepared SnS2/Ti3C2Tx HNs electrode delivers reversible capacities of 462.1 mAh g−1 at 0.1 A g−1 and 166.1 mAh g−1 at 2.0 A g−1, respectively, and a capacity of 85.5 mAh g−1 is remained even after 460 cycles at 2.0 A g−1. These results are superior to those of the counterpart electrode, confirming aggressive promotion of K-ion storage performance of SnS2 anode brought by the cooperation of Ti3C2Tx, and presenting a reliable strategy to improve the electrochemical performance of sulfide anodes.

Background Gestational diabetes mellitus (GDM) is a type of diabetes associated with pregnancy and may impose risks on both mother and fetus. Akt paeoniflorin was shown to have anti-inflammatory and anti-hyperglycemia properties and has a potential ability to suppress mammalian target of rapamycin (mTOR) signaling. The current study aimed to study the effect of paeoniflorin on GDM maternal, fetal, and placental characteristics in vivo. Methods Streptozotocin (STZ)-induced gestational diabetes rat model was used in our study. The expression levels of phosphorylation (p-) and total protein expression levels of protein kinase B (Akt), mTOR, serum/glucocorticoid regulated kinase 1 (SGK1), and eIF4E-binding protein 1 (4E-BP1) in the placenta were determined by Western blot assay. The blood glucose, insulin, and leptin levels were assessed using enzyme-linked immunosorbent assay (ELISA). Results We found that placental Akt/mTOR signaling was substantially upregulated in GDM patients compared with healthy donors. Paeoniflorin administration alleviates the dysregulation of blood glucose, leptin, and insulin levels in both maternal and fetal GDM rats. Paeoniflorin treatment suppressed the overactivation of Akt/mTOR signaling in placental tissues. More importantly, administration of paeoniflorin was beneficial for normalization of fetal size and body weight in the GDM rats. Conclusion Our study suggested that application of paeoniflorin may serve as a potential therapeutical strategy for patients with GDM.

Cuprous oxide (Cu2O) is an important p-type semiconductor and widely used in the electrocatalytic field. However, the limited number of active sites and its poor conductivity make it difficult to further improve its catalytic activity. Here, we adopt a two-step method involving the reduction of Cu2+ at alkaline conditions and low temperature as well as heat treatment to fabricate Cu–Cu2O heterostructures in the presence of PVP. When used as a catalyst for glucose oxidation, Cu–Cu2O heterostructure possesses abundant active sites to react with glucose molecules, and moreover the metallic Cu simultaneously provides a highly conductive path for electrical charge transfer during the electrocatalytic oxidation reaction of glucose. As a result, the Cu–Cu2O heterostructure exhibits enhanced electrocatalytic activity towards glucose oxidation in 0.1 M NaOH solution compared to only Cu2O, and the fabricated non-enzymatic glucose sensor offers a low detection limit of 1.4 μM (S/N = 3), a high sensitivity (1446 μA mM−1 cm−2), and a wide linear range (0.002–4 mM) at a working voltage of 0.55 V (vs. SCE) in alkaline solutions. The as-prepared Cu–Cu2O heterostructure has a high catalytic activity, providing a new strategy for the design of other electrocatalysts.

Conversion anode materials such as Mn

Layered metal sulfides are considered as promising candidates for potassium ion batteries (KIBs) owing to the unique interlayer passages for ion diffusion. However, the insufficient electronic conductivity, inevitable volume expansion, and sulfur loss hinder the promotion of K-ion storage performance. Herein, few-layered Ti

In this work, K2Ti6O13 nanorods have been synthesized and evaluated as potassium-ion battery anode material. A reversible capacity of 95.7 mAh g−1 at 0.01 A g−1 is obtained by this K2Ti6O13 nanorods electrode, and its robust structure survives after long cycling. Our result suggests that a solid–solution storage mechanism occurs to the K2Ti6O13 anode and the partial reversible redox reaction of Ti4+/Ti3+ contributes to the reversible capacity. The superior cycling stability of K2Ti6O13 nanorods electrode makes it a competitive KIBs anode for application on large-scale energy storage systems.

Modular multilevel converter (MMC) is drawing more and more attention in medium-voltage microgrid applications. Large-scale switching-off loads and grid faults may lead to the voltage swell in microgrid, where MMC should have the ride-through ability. In this paper, a simple operation approach with the fundamental and irregular zero-sequence voltage (ZSV) injection is proposed for MMC under grid voltage swell condition. First, the fundamental ZSV injection is applied to adjust the modulation margin of three phases where the amplitude values of modulation waves in each phase can be the same. Then, if the amplitudes with fundamental ZSV injection are still in over-modulation status, the new irregular ZSV injection is added to further enlarge the operation region. In addition, the limitation of the irregular ZSV injection is analyzed. Simulation and experimental results of MMC under different grid voltage swell conditions verify the effectiveness of the proposed operation approach.

Conversion-alloy sulfide materials for potassium-ion batteries (KIBs) have attracted considerable attention because of their high capacities and suitable working potentials. However, the sluggish kinetics and sulfur loss result in their rapid capacity degeneration as well as inferior rate capability. Herein, a strategy that uses the confinement and catalyzed effect of Nb

Al has been considered as a promising Li-ion batteries anode. However, the volume expansion always makes the electrode in an unstable structure. Meanwhile, the natural Al2O3 passivation layer may lead to a large voltage dip, which could interrupt the lithiation process and result in a limited capacity. Herein, we report a neat avenue to activate the commercial Al pellet electrode by replacing the Al2O3 layer with Sn at room temperature. Not any acid or tedious process is needed. Benefiting from the elimination of Al2O3 and high electrochemical-activity of Sn, the obtained Al@Sn pellet electrode delivers a reversible capacity of 959.5 mAh g-1 at 0.1 A g-1, which is larger than that (395.7 mAh g-1) of the commercial Al pellet electrode and approaches the calculated theoretical capacity. Notably, the voltage dip is muchly lowered to 0.03 V from 0.1 V. When graphene oxide (GO) was further attached for relieving the volume expansion, the as-prepared Al@Sn@GO pellet electrode presents astonishing Li-ion storage properties both in half and full batteries. This work demonstrates that the cooperation of the Al2O3 elimination and matrix addition is successful in promoting the Li-ion storage properties of Al anode, presenting an attractive vision for the development of practical Al-based anodes.

Remaining useful life (RUL) prediction for electric vehicle battery (EV battery) is of great significance for the early replacement and regular maintenance of batteries with potential safety hazards in driving conditions. This paper proposes a novel method based on light gradient boosting machine (LightGBM) to predict the RUL of the battery under driving conditions. LightGBM uses the histogram optimization strategy to reduce the number of traversal of the data sample set and improve the robustness of the method; the depth-first splitting (leaf-wise) strategy reduces the risk of overfitting; the gradient-based one-sided sampling strategy (GOSS), reduce the data dimension; use the exclusive feature bundling strategy (EFB) to reduce the feature dimension. However, the LightGBM method has the difficulty of parameter setting. Therefore, this paper uses Hyperopt based on distributed asynchronous algorithm configuration/hyperparameter optimization to optimize its complicated hyperparameters. Subsequently, the method was applied to the prediction of battery RUL under simulated driving conditions. Based on the comparative cases, the results show that this method can guarantee the rapidity, accuracy and robustness of RUL prediction under the condition of low memory usage.

Through a solvothermal reaction between the corresponding nickel(II) sulfate, π-electron rich tri-carboxylate ligand 4-(2′,3′-dicarboxylphenoxy) benzoic acid (H3L) and 1,2-bis (4-pyridyl) ethylene (bpe) molecule, a novel three-dimensional (3D) nickel-based coordination polymer (Ni-CP), namely [Ni3(L)2(bpe)3(H2O)4]·(H2O)6 (1) was successfully constructed. The structure was established by single-crystal X-ray diffraction, which reveals that 1 features a new 3,4,4-connected topology with the point symbol of (105·12) (4·102)2 (4·85)2. Subsequently, some studies on optical properties of compound 1 were carried out. Interestingly, the results suggest that compound 1 exhibits excellent applications as a fluorescent sensor for the recognition of Hacac via a fluorescence quenching approach. The detection limit can be as low as 10.19 µM. The possible mechanisms of the fluorescence turn-off effect were also discussed in detail. This work presents a case for monitoring Hacac concentrations in water samples.

A novel Cu(II) coordination polymer (compound 1) formulated as [Cu(HL)(bpy)]·H2O (H3L = 4-(2′,3′-Dicarboxylphenoxy) benzoic acid, bpy = 2,2′-bipyridine) has been successfully prepared via solvothermal methods and characterized by structural analyses. Crystallographic research reveals that compound 1 exhibits a 1D metal-carboxylate chain, which self-assembles into a final 3D supramolecular network through the interchain hydrogen bonds. Further investigation indicates that compound 1 possesses excellent chemical stability. It maintains good stability in various solvents and aqueous solution with pH range of 2–11 for two weeks. The luminescence investigations manifest that compound 1 can be used as a multi-responsive fluorescence sensor for sensing acetylacetone (Hacac), CrO42− and Cr2O72− with high selectivity, sensitivity and excellent anti-interference ability through luminescence quenching. Furthermore, the probable mechanisms of selective detection have been explored in detail.

Surface-enhanced Raman scattering (SERS) tags have attracted tremendous attention in diverse fields owing to their outstanding sensitivity and multiplexing capability. However, the selection of Raman dyes that can be immobilized onto metal nanoparticles is very limited, because certain chemical groups are needed in the dye molecules to interact either with the metal surface or through some intermediate layers. Here, we report a simple, rapid, and robust platform methodology for the one-pot preparation of Raman nanoprobes without the constraints of Raman dye chemical structures. We demonstrate this general approach by immobilizing dye molecules on silver nanoparticle surfaces that were difficult to incorporate previously, and show their applications in multiplexed immunohistochemistry (IHC). We expect that this platform nanotechnology will significantly expand the library of SERS tags and their biomedical uses.

A one-dimensional (1D) Ni(II) coordination polymer (CP), [Ni(H2L)2(bpe)(H2O)2]bpe·(H2O)4 (1) (H3L ​= ​4-(2′,3′-dicarboxylphenoxy) benzoic acid; bpe ​= ​1,2-bis(4-pyridyl) ethylene) was constructed from a semi-rigid tricarboxylate acid H3L. Owing to the extraordinary moisture susceptibility and fluorescence property, compound 1 displays high sensitive and selective detectivity as a dual-response fluorescence probe for ascorbic acid and acetylacetone in aqueous phase via fluorescence “turn on” and “turn off” mechanism, respectively. It's worth noting that 1 exhibits rare turn-on responsive effect to AA. Both proposed systems exhibit excellent performance with outstanding anti-interference ability as well as good reusability. Besides, the mechanisms of fluorescence sensing were also investigated in detail. This work expands the practical applications of stable CPs in the detection of biological molecules and organic pollutants in aqueous phase.

Conversion-reaction anode materials always deliver high capacities when used for Li-ion batteries (LIBs). However, the large voltage-hysteresis between the discharge and charge potentials slide down the round-trip efficiency of the electrodes, which restricts their further application on commercial LIBs. Herein, an assumption that lowering the voltage-hysteresis by constructing heterostructure is proposed and further verified by CuS based electrode. As a proof of concept, CuS/MnS heterostructure nanoparticles confined by carbon layers are designed and further crosslinked into a 3D network, constructing CuS/MnS-C heterostructure nanofibers (HNFs). The as-formed heterointerfaces facilitate the charge separation and transfer, and further improve the kinetics. Meanwhile, the confinement and conductive network of the carbon nanofibers improve the structural stability and conductivity of the hybrid electrode. As a result, the voltage-hysteresis values of the CuS anode are lowered to 0.30 and 0.35 V in the well-designed CuS/MnS-C HNFs electrode, much smaller than the original values (0.82 and 0.70 V) in the CuS-C NFs electrode. Moreover, the CuS/MnS-C HNFs electrode exhibits the best excellent rate capability among their counterpart electrodes (493.5 mAh g−1 at 2.0 A g−1 with the coulombic efficiency of about 100%). This work would shed light on the development of practical conversion-reaction anode materials with low voltage-hysteresis.

One new Co(II) coordination polymer was prepared by the hydrothermal method based on a semi-rigid tricarboxylate acid, 4-(2′,3′-dicarboxylphenoxy) benzoic acid (H3L) as [H2bpe][Co(HL)2(bpe)(H2O)2]·(H2O)4 (1) (bpe = 1,2-bis(4-pyridyl) ethylene). This compound has been characterized by single crystal and powder X-ray diffraction, elemental analysis, IR spectra, thermogravimetric analysis, and fluorescent properties. In particular, it is found that compound 1 possesses excellent chemical stability. More importantly, this material could act as a novel “turn-on” fluorescent probe for highly selectively sensitizing ascorbic acid (AA) and “turn-off” sensor for recognizing acetylacetone (Hacac) in the aqueous phase. Both proposed sensing systems showed excellent performance with high sensitivity and selectivity as well as good reusability. The detection limits are as low as 2.60 nM and 57.5 μM, respectively. In addition, the possible mechanism were detailedly discussed.

A new Cu(I)-coordination polymer [Cu2(bpp)2Cl]·Hapta·H2O (1) (H2apta = 4-aminophthalic acid, bpp = 1,2-bis(4-pyridyl)propane)) has been successfully designed and prepared. The crystal structure, C H N analysis, FTIR spectroscopy, XPS and intrinsic photophysical properties of compound 1 were investigated. In 1, two types of Cu(I) ions are separately consolidated by the two types of bidentate bpp ligands to construct a one-dimensional (1D) chain along the b axis. Adjacent 1D chains are further linked by the Cl ligand to induce a final 2D layer structure with a unique crb topology. Notably, the introduced H2apta linker only serve as guest molecule, occupying the space of the channels. More importantly, the fluorescence properties of 1 can be utilized to detect oxoanion Cr(VI) ions with high sensitivity and selectivity in aqueous solution through fluorescence quenching effect. The detection limits of 1 toward Cr2O72−, CrO42− are as low as 5.36 μM and 15.17 μM, respectively. Furthermore, the possible sensing mechanism has also been discussed in more detail.

We herein report a new manganese(II) coordination polymer (CP), [Mn(HL)(H2O)2]·(bpe)0.5 (1), which is incorporated with semi-rigid tricarboxylate 4-(2′,3′-dicarboxylphenoxy) benzoic acid (H3L) and 1,2-bis(4-pyridyl) ethylene (bpe) as organic linkers through self-assembly strategy. Single crystal X-ray diffraction indicates that compound 1 contains a one-dimensional (1D) chain structure, which self-assembles into a final three-dimensional (3D) supramolecular framework via the interchain hydrogen bondings. Noticeably, bpe molecules have no practical contribution to the construction of 1D chain structure of 1, which only act as the guest molecules improving the stability of the 3D supramolecular network. More remarkably, the fluorescence signals feature a highly selective and sensitive “turn-off” response toward Cr2O72− and acetylacetone (Hacac) highlighted with the low detection limits of 4.44 μM and 6.11 ppm, respectively. The linear range for Hacac detecting is 0–5.0 mM, while 0–100 μM for Cr2O72−. Therefore, the exceptional sensing performance render compound 1 a potential platform for dually probe Hacac and oxo-anion Cr2O72− in wastewater. The crystal structure, selective sensing behavior and probable sensing mechanism of 1 toward both analytes are discussed in detail.

Potassium-ion batteries (KIBs) are considered to be promising energy-storage-systems in the post-Li-ion batteries. Conversion and alloy reaction anode materials draw much attention owing to high theoretical capacities. However, their inherent volume expansions always block the K-ion diffusion or interrupt electron transfer to a degree, resulting in degraded performances at high rates. It is supposed that the rate capability of the anode would be improved when the avenues for ion/electron are kept expedite simultaneously. Herein, SnS2 and carbon hybrid submicro-fibers with optimized channels were prepared as integrated KIBs electrodes to clarify the effect of the bi-continuous avenues on the rate capability. In this configuration, SnS2 nanosheets are confined by carbon and further crosslinked into 3D network. The 3D carbon submicro-fibers are adopted as a network for electron transfer, while the channels play the role of ion diffusion avenues. Owing to the stable and expedite bi-continuous electron/ion avenues, the rate capability of the SnS2@C–1V1 SMF electrode (137.5 mAh g−1 at 2.0 A g−1) is improved when compared to the counterparts (3.6 mAh g−1 and 94.5 mAh g−1 at the same condition). This work will offer an important reference for the optimization design and construction of KIBs anode materials with high rate capability.

Sulfur is a promising alternative lithium battery cathode for its low cost, abundance, and high specific capacity. However, issues of rapid capacity decay and low coulombic efficiency hamper its practical application pace owing to polysulfides dissolution. Despite efforts on hybridizing sulfur with metal oxides to solve these issues are considered to be effective, the synthesis of hybrid materials is always tedious. Herein, S@MnO2 hybrid material was synthesized via a green method at room temperature. We encapsulate S spheres in poly-dopamine (PDA) by in-situ polymerization of dopamine. The formed PDA shell is served as reducing agent and sacrificial template to transform KMnO4 into δ-MnO2 shell without adding any other agents (such as acid). δ-MnO2 encapsulates the S spheres uniformly and succeeded in entrapping polysulfides when S@MnO2 used for Li–S battery, endowing the S@MnO2 cathode with high reversible capacity, improved cycling stability, and satisfied coulombic efficiency. Moreover, this method could be adopted for hybridizing δ-MnO2 with diverse materials (such as CNTs@MnO2) in mild reaction environment (ambient pressure and temperature), exhibiting an extensive application on constructing Mn-based oxide hybrid functional materials.

// Yating Wang 1, * , Yan Liu 1, * , Huiqiao Liu 1, * , Qingan Zhang 2 , Hongyan Song 3 , Jianliang Tang 4 , Jiangtao Fu 1 and Xiaofei Wang 1 1 Department of Otolaryngology Head and Neck Surgery, Lishui People’s Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang, China 2 Department of Clinical Laboratory, The Central Hospital of Linyi, Yishui, Shandong, China 3 Department of Otolaryngology, Yunhe People’s Hospital, Yunhe, Zhejiang, China 4 Department of Psychiatry, Tongxiang First People’s Hospital, Tongxiang, Zhejiang, China * These authors have contributed equally to this work Correspondence to: Xiaofei Wang, email: LSJNWWF@163.com Jiangtao Fu, email: 18957091188@163.com Jianliang Tang, email: jianliangtang@126.com Keywords: FcGBP, HPV, HNSCC, TGF-β, migration Received: July 12, 2017 Accepted: August 09, 2017 Published: September 23, 2017 ABSTRACT FcGBP was normally found in intestinal and colonic epithelia, gallbladder, cystic duct, bronchus, submandibular gland, cervix uteri and in fluids secreted by these cells in humans, and was down-regulated during colon carcinogenesis. We found FcGBP gene expression was decreased in HNSCC tissues compared to surgical safety border tissues while TGF-β expression level increased in HNSCC tissues, and higher FcGBP expression level was correlated to longer OS time of HNSCC patients. FcGBP expression level was higher in HPV-positive HNSCC tissues compared to HPV-negative HNSCC tissues, while TGF-β expression level was lower in HPV-positive HNSCC tissues. Gene expression level of FcGBP and TGF-β was negatively correlated in HNSCC tissues. FcGBP expression level increased after HPV E6 overexpression in HPV-negative HNSCC cells, and TGF-β could inhibit the up-regulation of FcGBP after HPV E6 or FcGBP overexpression in HPV-negative HNSCC cells. The migration capability was inhibited after FcGBP overexpression, and TGF-β could counteract the inhibition of migration caused by FcGBP overexpression. FcGBP gene expression level was correlated to the expression levels of EMT markers. In conclusion, FCGBP expression was upregulated by HPV infection while inhibited by TGF-β, and was correlated to the prognosis of HNSCC patients.

Precise profiling of the sialic acid (SA) expression on the membrane of cancer cells is critical for early identification of cancers and assessment of cancer metastasis. However, the complex physiological environments often result in false positives with currently available imaging technologies. Herein, we have established a background-free surface-enhanced Raman scattering (SERS) imaging platform that allows high-precision profiling of SA expression in cancer cells and differentiation of clinically relevant cancer tissues with various metastasis degrees. Three-dimensional Raman imaging technique provided a deeper insight into visualizing the probe distribution and thus the SA expression at the single-cell level, without destructing the cells. This noninvasive, high-precision imaging technique could favor early diagnosis, staging, and monitoring therapeutic responses of cancers that are highly essential in clinical settings.

Single-molecule detection using surface-enhanced Raman spectroscopy (SERS) has attracted increasing attention in chemical and biomedical analysis. However, it remains a major challenge to probe single biomolecules by means of SERS hot spots owing to the small volume of hot spots and their random distribution on substrates. We here report an in situ hot-spot assembly method as a general strategy for probing single biomolecules. As a proof-of-concept, this proposed strategy was successfully used for the detection of single microRNA-21 (miRNA-21, a potential cancer biomarker) at the single-cell level, showing great capability in differentiating the expression of miRNA-21 in single cancer cells from normal cells. This approach was further extended to single-protein detection. The versatility of the strategy opens an exciting avenue for single-molecule detection of biomarkers of interest and thus holds great promise in a variety of biological and biomedical applications.

Potassium-ion batteries (KIBs) are promising alternatives to lithium-ion batteries because of the abundance and low cost of K. However, an important challenge faced by KIBs is the search for high-capacity materials that can hold large-diameter K ions. Herein, copper oxide (CuO) nanoplates are synthesized as high-performance anode materials for KIBs. CuO nanoplates with a thickness of ≈20 nm afford a large electrode-electrolyte contact interface and short K+ ion diffusion distance. As a consequence, a reversible capacity of 342.5 mAh g-1 is delivered by the as-prepared CuO nanoplate electrode at 0.2 A g-1 . Even after 100 cycles at a high current density of 1.0 A g-1 , the capacity of the electrode remains over 206 mAh g-1 , which is among the best values for KIB anodes reported in the literature. Moreover, a conversion reaction occurs at the CuO anode. Cu nanoparticles form during the first potassiation process and reoxidize to Cu2 O during the depotassiation process. Thereafter, the conversion reaction proceeds between the as-formed Cu2 O and Cu, yielding a reversible theoretical capacity of 374 mAh g-1 . Considering their low cost, easy preparation, and environmental benignity, CuO nanoplates are promising KIB anode materials.

As indispensable components of potassium ion batteries (KIBs), anode materials are on the focus and their developments are important for boosting the application of KIBs. Tin sulfide (SnS2) is considered as an ideal KIBs anode material owing to its high theoretical capacity (733 mAh g−1) and the unique layered structure. However, the huge volume deformation and potassium polysulfide intermediates dissolution hinder the enhancement of the electrochemical performance of SnS2 anode. Herein, SnS2 nanosheets supported by N, S-doped carbon (N, S-C/SnS2 nanosheets) were synthesized by an in-situ carbonization and sulfuration method with one step. In the formed architecture, the N, S-doped carbon not only works as matrix to stabilize the microstructure of the hybrid material, but also serves as the reservoir to trap polysulfides for alleviating the loss of sulfur element in SnS2. Thanks to these merits, a high reversible capacity (614.8 mAh g−1 at 0.1 A g−1), as well as good rate capability (104.5 mAh g−1 at 2.0 A g−1) are achieved by the N, S-C/SnS2 nanosheets electrode. This work offers a concise method to construct SnS2 hybrid material, and demonstrates that K+ ion storage property of conversion-alloy reaction mechanism sulfide anodes can be remarkably enhanced by elegant structure design.

Mn3O4 is considered as a promising lithium-ion batteries (LIBs) anode material owing to the high theoretical capacity, appropriate lithiation potential, low cost, and environmentally benign nature. However, the inferior electronic conductivity and dramatic volume expansion during cycling hinder the enhancement of Li ion storage property. Herein, Mn3O4 nanoparticles with the dimension about 18 nm anchoring on carbon nanotubes (CNTs@Mn3O4) are fabricated using CNTs@MnO2 as precursor, which is prepared by a facile method at room temperature. Benefiting from the merits brought by the microstructure and components of hybrid material, the as-prepared CNTs@Mn3O4 electrode delivers a reversible capacity of 895.0 mAh g−1 at 0.5 A g−1 after 200 cycles and 743.7 mAh g−1 at 5.0 A g−1 when used as LIBs anode. Considering the multifunctional property of Mn-based oxides, this work presents a facile method to synthesize Mn-based functional materials for various fields.

Quantifying trace microRNAs (miRNAs) is extremely important in a number of biomedical applications but remains a great challenge. Here we present an enzyme-free amplification strategy called plasmon-enhanced hybridization chain reaction (PE-HCR) for quantifying trace miRNAs with an outstanding linear range from 1 fM to 1 pM (r(2) = 0.991), along with a detection limit of 0.043 fM (1300 molecules in 50 μL of sample). The merits of the PE-HCR assay, including high sensitivity and specificity, quantitative detection, no enzyme involvement, low false positives, and easy-to-operate procedures, have been demonstrated for high-confidence quantification of the contents of miRNAs in even single cancer cells. The PE-HCR assay may open up new avenues for highly sensitive quantification of biomarkers and thus should hold great potentials in clinical diagnosis and prognosis.

In this communication, FeMnO3 particles were prepared and evaluated as an anode material for Li ion batteries. This electrode shows high capacity, excellent rate capability, and good cycling stability (984 mA h g−1 at 1.0 A g−1 after 500 cycles). Moreover, the Li storage mechanism is studied.

Rapid and convenient biosensing platforms could be beneficial to timely diagnosis and treatment of diseases in virtually any care settings. Sandwich immunoassays, the most commonly used methods for protein detection, often rely on expensive tags such as enzyme and tedious wash and incubation procedures operated by skilled labor. In this report, we revolutionized traditional sandwich immunoassays by providing a wash-free homogeneous colorimetric immunoassay method without requirement of any separation steps. The proposed strategy was realized by controlling the growth of gold nanoparticles (AuNPs) to mediate the interparticle spacing in the protein-AuNP oligomers. We have demonstrated the successful in vitro detection of cancer biomarker in serum samples from patients with high clinical sensitivity and specificity.

In this work, 3D hierarchical flower-like MoS 2 spheres are successfully fabricated via a hydrothermal method followed by a heat treatment. The obtained product is composed of few-layered MoS 2 nanosheets with enlarged interlayer distance (ca. 0.66 nm) of the (002) plane. Meanwhile, the hydrogen storage properties of the as-prepared MoS 2 ball milled with LiBH 4 are systematically investigated. The results of temperature programmed desorption (TPD) and isothermal measurement suggest that the LiBH 4 –MoS 2 (as-prepared) mixture exhibits favorable dehydrogenation properties in both lowering the hydrogen release temperature and improving kinetics of hydrogen release rate. LiBH 4 –MoS 2 (as-prepared) sample (the preparation mass ratio is 1:1) starts to release hydrogen at 171 °C, and roughly 5.6 wt% hydrogen is released within 1 h when isothermally heated to 320 °C, which presents superior dehydrogenation performance compared to that of the bulk LiBH 4 . The excellent dehydrogenation performance of the LiBH 4 –MoS 2 (as-prepared) mixture may be attributed to the high active site density and enlarged interlayer distance of the MoS 2 nanosheets, 3D architectures and hierarchical structures.

To inhibit the aggregation of TiO2 nanoparticles and to improve the electrochemical kinetics of TiO2 electrode, a hybrid material of ultrasmall TiO2 nanoparticles in situ grown on rGO nanosheets was obtained by ultraphonic and reflux methods. The size of the TiO2 particles was controlled about 10 nm, and these particles were evenly distributed across the rGO nanosheets. When used for the anode of a sodium ion battery, the electrochemical performance of this hybrid TiO2@rGO was much improved. A capacity of 186.6 mAh g(-1) was obtained after 100 cycles at 0.1 A g(-1), and 112.2 mAh g(-1) could be maintained at 1.0 A g(-1), showing a high capacity and good rate capability. On the basis of the analysis of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), the achieved excellent electrochemical performance was mainly attributed to the synergetic effect of well-dispersed ultrasmall TiO2 nanoparticles and conductive graphene network and the improved electrochemical kinetics. The superior electrochemical performance of this hybrid material on lithium storage further confirmed the positive effect of rGO.

Although transition metal oxide electrodes have large lithium storage capacity, they often suffer from low rate capability, poor cycling stability, and unclear additional capacity. In this paper, CoO nanowire clusters (NWCs) composed of ultra-small nanoparticles (≈10 nm) directly grown on copper current collector are fabricated and evaluated as an anode of binder-free lithium-ion batteries, which exhibits an ultra-high capacity and good rate capability. At a rate of 1 C (716 mA g−1), a reversible capacity as high as 1516.2 mA h g−1 is obtained, and even when the current density is increased to 5 C, a capacity of 1330.5 mA h g−1 could still be maintained. Importantly, the origins of the additional capacity are investigated in detail, with the results suggesting that pseudocapacitive charge and the higher-oxidation-state products are jointly responsible for the large additional capacity. In addition, nanoreactors for the CoO nanowires are fabricated by coating the CoO nanowires with amorphous silica shells. This hierarchical core–shell CoO@SiO2 NWC electrode achieves an improved cycling stability without degrading the high capacity and good rate capability compared to the uncoated CoO NWCs electrode.

Electromagnetic hot spots of surface-enhanced Raman scattering have been extensively employed for bioanalysis in solution or on a substrate, but building hot spots in living systems for probing targets of interest has not been achieved yet because of the complex and dynamic physiological environment. Herein, we show that a target-programmed nanoparticle dimerization can be combined with the background-free Raman reporters (alkyne, C≡C; nitrile, C≡N) for multiplexed imaging of microRNAs (miRNAs) in living cells. The in situ formation of plasmonic dimers results in an intense hot spot, thus dramatically enhancing the Raman signals of the reporters residing in the hot spot. More significantly, the reporters exhibit single nonoverlapping peaks in the cellular Raman-silent region (1800–2800 cm–1), thus eliminating spectral unmixing and background interference. A 3D Raman mapping technique was harnessed to monitor the spatial distribution of the dimers and thus the multiple miRNAs in cells. This approach could ...

Controlling the electromagnetic hot-spot generation is essential for surface-enhanced Raman scattering (SERS) assays. Current hot-spot-based SERS assays have been extensively studied in solutions or on substrates. However, probing biospecies by controlling the hot-spot assembly in living systems has not been demonstrated thus far. Herein, we report a background-free SERS probe for imaging pyrophosphate (PPi), a biochemically significant anion, in living cells. Intracellular PPi is able to induce the nanoparticle dimerization, thus creating an intense electromagnetic hot spot and dramatically enhancing the signal of the Raman reporters residing in the hot spot. More impressively, the reporter we used in this study provides a strong and sharp single peak in the cellular Raman-silent region (1800–2800 cm–1), thus eliminating the possible background interference. This strategy could be readily extended to detect other biomarkers by only replacing the recognition ligands.

We report a surprising discovery that Prussian blue (PB) can be employed as a highly sensitive and background-free resonant Raman reporter. Conventional Raman reporters show multiple spectral bands in the fingerprint region, which are generally overlapped with those from dominant endogenous biomolecules, and are thus difficult to be separated. Herein, we found that PB only possesses a strong and sharp single-band in the cellular Raman-silent region, where no Raman signals from biological species were observed. Therefore, the Raman spectra from PB and endogenous biomolecules are completely resolved without resorting to complicated spectral unmixing. Moreover, PB holds a strong UV-vis absorption band between 500 and 900 nm, which is resonant with the incident detection lasers, providing extremely high sensitivity. Through assembly of PB onto plasmonic cores, a new surface-enhanced resonance Raman scattering (SERRS) probe was achieved with a high signal-to-background ratio (SBR). We demonstrated the performance of the PB-based SERRS tags for high-sensitivity immunoassay and cancer cell imaging.

We presented a Janus PEGylated AuNP probe where PEGs and recognition ligands (e.g., 4-aminobenzenethiol, 4-ABT) were asymmetrically functionalized on an AuNP. With this design, the probes showed high colloidal stability, signal robustness, specificity, and sufficient sensitivity in the determination of NO2- in various complex samples.