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In this communication, a reconfigurable 2-bit leaky-wave antenna (LWA) is proposed for low-cost fixed-frequency beam-steering applications. The proposed antenna consists of a microstrip transmission line loaded with several branches, a series of 2-bit phase shifters, and a $1\times 8$ patch array. Each phase shifter is built by selecting the feed directions on the branch and introducing slot perturbation on the patch, thus no phase delay line is used. Only three p-i-n diodes are needed to control the 0°, 90°, 180°, and 270° states of the element. The reference phase $\varphi _{0}$ , namely the phase of the first element, is utilized to enhance the peak gain of the array. The stopband effect of broadside beam is eliminated due to the perturbation on the patches. The prototype is tested at 3.6 GHz. The measured peak gain is 13.54 dBi, and the main beam can steer from $- \mathrm{48}^{\circ }$ to $+ \mathrm{46}^{\circ }$. [ABSTRACT FROM AUTHOR]

Circulating tumour DNA (ctDNA) has emerged as an ideal biomarker for the early diagnosis and prognosis of gastric cancer (GC). In this work, a pump-free, high-throughput microfluidic chip coupled with catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR) as the signal cascade amplification strategy (CHA–HCR) was developed for surface-enhanced Raman scattering (SERS) assays of PIK3CA E542K and TP53 (two GC-related ctDNAs). The chip consisted of six parallel functional units, enabling the simultaneous analysis of multiple samples. The pump-free design and hydrophilic treatment with polyethylene glycol (PEG) realized the automatic flow of reaction solutions in microchannels, eliminating the dependence on external heavy-duty pumps and significantly improving portability. In the reaction region of the chip, products generated by target-triggered CHA initiated the HCR, forming long nicked double-stranded DNA (dsDNA) on the Au nanobowl (AuNB) array surface, to which numerous SERS probes (Raman reporters and hairpin DNA-modified Cu2O octahedra) were attached. This CHA–HCR strategy generated numerous active "hot spots" around the Cu2O octahedra and AuNB surface, significantly enhancing the SERS signal intensity. Using this chip, an ultralow limit of detection (LOD) for PIK3CA E542K (1.26 aM) and TP53 (2.04 aM) was achieved, and the whole process was completed within 13 min. Finally, a tumour-bearing mouse model was established, and ctDNA levels in mouse serum at different stages were determined. To verify the experimental accuracy, the gold-standard qRT–PCR assay was utilized, and the results showed a high degree of consistency. Thus, this rapid, sensitive and cost-effective SERS microfluidic chip has potential as an ideal detection platform for ctDNA monitoring. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) remains a significant contributor to the global mortality rate, and a single biomarker cannot meet the specificity required for CRC screening. To this end, we developed a multiplexed, pump-free surface-enhanced Raman scattering (SERS) microfluidic chip (LoC-SERS) using a one-step recognition release mechanism; the aptamer-functionalized novel Au nanocrown array (AuNCA) was used as the detection element embedded in the detection zone of the platform for rapid and specific detection of protein markers in multiple samples simultaneously. Here, the corresponding aptamer specifically captured the protein marker, causing the complementary strand of the aptamer carrying the Raman signal molecule to be shed, reducing the SERS signal. Based on this platform, sensitive and specific detection of the target can be accomplished within 15 min with detection limits of 0.031 pg/mL (hnRNP A1) and 0.057 pg/mL (S100P). Meanwhile, the platform was consistent with ELISA results when used to test clinical. By substituting different aptamers, this platform can provide a new solution for the rapid and sensitive detection of protein markers, which has promising applications in future disease detection. [Display omitted] • A POCT platform was developed for rapid and sensitive detection of protein markers. • The prepared AuNCA has good SERS signal amplification effect. • The platform can complete the detection of a target in less than 15 min. • The platform has a promising application in clinical testing. [ABSTRACT FROM AUTHOR]

An innovative surface-enhanced Raman spectroscopy and lateral flow assay (SERS-LFA) biosensor combined with aptamer recognition had been developed for the convenient, rapid, sensitive and accurate detection of thrombin and platelet-derived growth factor-BB (PDGF-BB) associated with prostate cancer simultaneously. During the biosensor operation, thrombin and PDGF-BB in the sample were recognized and combined by thiol-modified aptamers immobilized on Au–Ag hollow nanoparticles (Au–Ag HNPs) surface and biotinylated aptamers immobilized on the test lines of the biosensor. Thus, thrombin and PDGF-BB were simultaneously captured between detection aptamers and capture aptamers in a sandwich structure. Finite difference time domain simulation confirmed that 'hot spots' appeared at the gaps of Au–Ag HNPs dimer in the enhanced electromagnetic field compared to that of a single Au–Ag HNP, indicating that the aggregated Au–Ag HNPs owned a good SERS signal amplification effect. The detection limits of thrombin and PDGF-BB in human plasma were as low as 4.837 pg ml−1 and 3.802 pg ml−1, respectively. Moreover, the accuracy of the biosensor which was applied to detect thrombin and PDGF-BB in prostate cancer plasma had been verified. This designed biosensor had broad application prospects in the clinical diagnosis of prostate cancer. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is a good candidate for the development of fast and easy-to-use diagnostic tools, possibly used on serum in screening tests. In this study, a potential label-free serum test based on SERS spectroscopy was developed to analyze human serum for the diagnosis of the non-small cell lung cancer (NSCLC). We firstly synthesized novel highly branched gold nanoparticles (HGNPs) at high yield through a one-step reduction of HAuCl4 with dopamine hydrochloride at 60°C. Then, HGNP substrates with good reproducibility, uniformity, and high SERS effect were fabricated by the electrostatically assisted (3-aminopropyl) triethoxysilane-(APTES-) functionalized silicon wafer surface-sedimentary self-assembly method. Using as-prepared HGNP substrates as a high-performance sensing platform, SERS spectral data of serum obtained from healthy subjects, lung adenocarcinoma patients, lung squamous carcinoma patients, and large cell lung cancer patients were collected. The difference spectra among different types of NSCLC were compared, and analysis result revealed their intrinsic difference in types and contents of nucleic acids, proteins, carbohydrates, amino acids, and lipids. SERS spectra were analyzed by principal component analysis (PCA), which was able to distinguish different types of NSCLC. Considering its time efficiency, being label-free, and sensitivity, SERS based on HGNP substrates is very promising for mass screening NSCLC and plays an important role in the detection and prevention of other diseases. [ABSTRACT FROM AUTHOR]

In this paper, we reported a simple one-step synthesis of highly-branched gold nanostructures (HGNs) in high yields. The reduction of HAuCl4 was accomplished by dopamine hydrochloride in the reaction system. By varying the amount of dopamine hydrochloride, HAuCl4 and the reaction temperature, we managed to tune the size of the HGNs from 200 to 600 nm. Systematic analysis revealed that the optical properties and surface-enhanced Raman scattering (SERS) activities of the HGNs were highly dependent on their morphology and size. In terms of their SERS activities, it was found that the HGNs synthesized at 60 °C with 2.0 mL dopamine hydrochloride (53 mM), 0.4 mL HAuCl4 (50 mM) exhibited the largest SERS enhancement. When the HGNs were assembled onto the silicon wafers, outstanding SERS efficiency was obtained with a detection limit of 5×10-10 M of 4-mercaptobenzoic acid (4-MBA) and the analytical enhancement factor (AEF) was calculated to be 7×107. Besides, the 3-aminopropyltriethoxysilane (APTES)-functionalized substrates with the HGNs displayed remarkable signal reproducibility with relative standard deviation (RSD) of 3.57%. All these results demonstrated that the SERS-active substrates held great promise to be applied in trace-level molecule detection in the future. [ABSTRACT FROM AUTHOR]

Manipulating particle size is a powerful means of creating unprecedented applications in both inorganic and organic materials. Coordination polymers, which are emerging as a type of organic–inorganic hybrid materials, have attracted thriving interest in a variety of applications, but nanoscale coordination polymers have scarcely been touched. In this work, the pure-phase {Cu6[1,4-bis(imidazol-1-yl)butane]3I6}∞ coordination polymer with different sizes and morphologies was synthesized for the first time through a facile top-down route assisted by solvent etching. The size and morphology could be adjusted simply by varying the participating etching solvents. Our mechanistic investigations suggest that the bulk coordination polymer as a precursor in the etching solvents may experience a process of dispersion, dissolution, and recrystallization to generate the nanoscale counterpart. High catalytic activity of the nanoscale coordination polymer was observed in the N-arylation of imidazole aryl halides, and this was attributed to a high surface area and a low coordination number of unsaturated coordination sites. This simple and rapid preparation, requiring neither specialized equipment nor harsh conditions, suggests a wealth of potential for reducing the size of coordination polymers to comply with various practical applications. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are recognized as regulators of gene expression during the biological processes of cells as well as biomarkers of many diseases. Development of rapid and sensitive miRNA profiling methods is crucial for evaluating the pattern of miRNA expression related to normal and diseased states. This work presents a novel hollow Au nanoflowers (HAuNFs) substrate for rapid detection and identification of miRNAs by surface-enhanced Raman scattering (SERS) spectroscopy. We synthesized the HAuNFs by a seed-mediated growth approach. Then, HAuNFs substrates were fabricated by depositing HAuNFs onto the surfaces of (3-aminopropyl)triethoxysilane- (APTES-) functionalized ITO glass. The result demonstrated that HAuNFs substrates had very good reproducibility, homogeneous SERS activity, and high SERS effect. The substrates enabled us to successfully obtain the SERS spectra of miR-10a-5p, miR-125a-5p, and miR-196a-5p. The difference spectra among the three kinds of miRNAs were studied to better interpret the spectral differences and identify miRNA expression patterns with high accuracy. The principal component analysis (PCA) of the SERS spectra was used to distinguish among the three kinds of miRNAs. Considering its time efficiency, being label-free, and its sensitivity, the SERS based on HAuNFs substrates is very promising for miRNA research and plays an important role in early disease detection and prevention. [ABSTRACT FROM AUTHOR]

In this work, Au nanobowl (AuNB) arrays and the hybridization chain reaction (HCR) were utilized to develop a surface-enhanced Raman scattering (SERS) microfluidic chip for the ultrasensitive and simultaneous detection of squamous cell carcinoma antigen (SCCA) and cytokeratin 19 fragment antigen 21–1 (CYFRA21–1) in the serum of cervical cancer patients. Antibody-oligonucleotide conjugates were adopted as triggers, which initiated HCR by the hybridization between hairpin DNAs that were modified on Raman reporters-labeled Ag nanocubes, forming nicked double-stranded DNAs on AuNB arrays and leading to SERS signal amplification. Good linear response in the range of 10-12 – 10-6 g/mL, with an ultralow limit of detection for SCCA (0.08 pg/mL) and CYFRA21–1 (0.13 pg/mL), was achieved. Furthermore, the experiments demonstrated that the chip was feasible, time-efficient, and selective. The proposed chip was successfully applied to detect SCCA and CYFRA21–1 in clinical samples, and the results were consistent with those of enzyme-linked immunosorbent assay. Since most protein biomarkers in serum lack the corresponding aptamers, this method, which establishes antibody-oligonucleotide conjugates to trigger HCR, provides a general signal amplification technology for detecting protein biomarkers and exhibits good potential in clinical applications. • A SERS microfluidic chip based on AuNBs array and HCR was developed and employed for clinical detection. • Antibody-oligonucleotide conjugates were established to connect with targets and initiate HCR for signal amplification. • The assay possessed high sensitivity, with LODs as low as 0.08 pg/mL for SCCA and 0.13 pg/mL for CYFRA21-1. • The SERS microfluidic chip realized automatic flow by hydrophilic treatment and comb-like structure channels. [ABSTRACT FROM AUTHOR]

Ca 2 TiMnO 6 compounds were synthesized by the conventional solid-state reaction in air. The crystal structure and magnetic properties were investigated. Characterization of X-ray diffractions and the refinement analysis confirmed the orthorhombic (space group Pbnm) structure of Ca 2 TiMnO 6 at room temperature. Magnetic measurements reveal that the double perovskite Ca 2 TiMnO 6 has antiferromagnetic interactions at low temperature and a paramagnetic order above 40 K. According to the Curie–Weiss fitting at high temperature, the Neel constant θ p and experimental efficient moment μ eff was estimated to be about −161.98 K and 4.91 μ B , respectively. The theoretical efficient moment was calculated to be 3.87 μ B . The XPS analysis indicates that the difference between experimental and theoretical efficient moment caused by the mixed valence state of Mn in Ca 2 TiMnO 6 . The temperature dependence of coercivity field shows a soft magnetic property in Ca 2 TiMnO 6 oxides. The mechanism of the low temperature anomaly which was appeared in magnetization curve was discussed in detail. [ABSTRACT FROM AUTHOR]

Circulating tumour DNAs (ctDNAs) have been reported to be associated with real-time information of progression; however, an accurate and sensitive method has not been established. Herein, a novel dual-signal amplification strategy based on a pump-free surface-enhanced Raman scattering (SERS) microfluidic chip and a catalytic hairpin assembly (CHA) technique was developed for the dynamic monitoring of BRAF V600E and KRAS G12V, which are two non-small cell lung cancer (NSCLC)-related ctDNAs. In the presence of targets, CHA reactions can be triggered between two hairpin DNAs, fixing Pd-Au core-shell nanorods (Pd-AuNRs) onto the magnetic beads (MBs) surface. Thereafter, the composite structures can assemble under the action of magnet, enabling dual-amplification of SERS signal. Using this strategy, the limit of detection (LOD) was low (i.e. at the aM level) in serum. Furthermore, the entire chip-based analysis process could be completed within 5 min, eliminating manual incubation and heavy-duty injection pumps. The selectivity, reproducibility and uniformity of the proposed pump-free SERS microfluidic chip were satisfactory. This superior analysis strategy was finally applied to quantify BRAF V600E and KRAS G12V in tumour-bearing nude mice serum, the results of which corresponded with those of real-time polymerase chain reaction. Overall, this study provides a promising alternative tool for the dynamic monitoring of ctDNA expression level which can benefit the clinical diagnosis of NSCLC. • CHA-induced powerful cycle amplification and the aggregation effect caused by MBs significantly enhanced the sensitivity of proposed pump-free SERS microfluidic chip, with the LODs low to aM level. • The pump-free SERS microfluidic chip presented satisfactory uniformity, stability, specificity and reproducibility. • This dual-signal amplification strategy could be applied for the dynamic monitoring expression of ctDNA in mice serum at different stages. [ABSTRACT FROM AUTHOR]

Lung resident mesenchymal stem cells (LR-MSCs) are important regulators of pathophysiological processes including tissue repair and fibrosis, inflammation, angiogenesis and tumor formation. Therefore, increasing attention has focused on the functional differentiation of LR-MSCs. However, the distinction between the undifferentiated and differentiated LR-MSCs, which are closely related and morphologically similar, is difficult to achieve by conventional methods. In this study, by employing the TAT Peptide-conjugated Au nanostars (AuNSs) as an intracellular probe, we developed a method for the identification of LR-MSC differentiation by surface-enhanced Raman scattering (SERS) spectroscopy. SERS spectra were analyzed using principal component analysis (PCA) that allowed unambiguous distinction of subtypes and monitoring of component changes during cellular differentiation. Furthermore, to ascertain whether co-culture with alveolar epithelial type II (ATII) cells and incubation with transform growth factor (TGF)-β were involved in regulating the differentiation of LR-MSCs, we investigated the protein expression levels of epithelial markers and fibroblastic markers on LR-MSCs. Our results demonstrated that co-culture with ATII cells or incubation with TGF-β could induce the differentiation of LR-MSCs as confirmed by SERS analysis, a method that is capable of noninvasive characterization of and distinction between subtypes of LR-MSCs during differentiation. We have provided a new tool that may facilitate stem cell research. [ABSTRACT FROM AUTHOR]

Over the past few decades, bistable [2]rotaxanes have been extensively studied because of their applications in molecular switches. In this paper, a rotaxane molecule containing a dibenzo-24-crown-8 ring and Rhodamine B units was synthesized and characterized by 1 H NMR and HRMS. The Rhodamine B component allows the fluorophore fluorescence to be manipulated in alternate modes by varying the pH of the solution under irradiation. Because of the easy regulation and high sensitivity of the changes in fluorophore fluorescence, Rhodamine B [2]rotaxane can be used as a molecular switch, with different pH values as the input and changes in the fluorescence intensity as the output signals. [ABSTRACT FROM AUTHOR]

In this paper, we report a novel antibody conjugated gold nanostars () as surface-enhanced Raman spectroscopy (SERS) probes for distinguishing cancer cells (A549 cells, H1229 cells) from normal cells (ATII cells). In such a probe, bovine serum albumin (BSA) was served as the protective agent and stabilizing agent, 4-mercaptobenzoic acid (4-MBA) was used as the Raman reporter to generate SERS signals as well as the conjugation agent for attaching CD44 antibody (anti-CD44) molecules to , where anti-CD44 could effectively target to CD44 protein over-expressed cells. All the results of the experiments confirmed that more SERS probes have been targeted to cancer cells (A549 cells and H1229 cells) than that of normal cells (ATII cells) under the same condition. The anti-CD44 SERS probes hold a potential application in distinguishing cancer cells from normal cells with high sensitivity and good biocompatibility. BSA-stabilized Au nanostars were synthesized with a seed-mediated growth approach in two steps, in which trisodium citrate dehydrate was used as the reducing agent. In SERS probes, 4-MBA was absorbed on the surface of Au nanostars as both the Raman reporter molecule and the conjugation agent for antibody, which could target to different cells through the combination of featured proteins on the cell membrane. [ABSTRACT FROM AUTHOR]

A novel rhodamine B-based sensor 1 consisting of a rhodamine B moiety linked to the amine end of a 1,4,7,10-tetraoxa-13-azacyclopentadecane was designed and synthesized. Sensor 1 exhibits a high selectivity for Fe 3+ in the presence of many other metal cations in a MeOH/H 2 O (1:1, v/v, pH = 7.4) solution. The binding analysis using a Job plot suggested that sensor 1 formed a 1:1 complex with Fe 3+ . The Fe 3+ binding ability of 1 was further demonstrated by DFT calculations. Fluorescence microscopy experiments demonstrated that sensor 1 can be used as a fluorescent probe for the detection of Fe 3+ in human liver cells (L-02) and rat neuronal cells (PC12). [ABSTRACT FROM AUTHOR]

Abstract: In this article, for the first time, a novel, high-yield and template-free method for the synthesis of Ag nanoparticle decorated thionine/infinite coordination polymer (AgNP/THI/ICP) fibres is proposed. The thionine can be adsorbed to the AgNP/THI/ICP fibres by π-conjugation and act as the redox probe. The AgNP/THI/ICP fibres not only favor the immobilization of antibody but also facilitate the electron transfer. It is found that the AgNP/THI/ICP fibres can be designed to act as a sensitive label-free electrochemical immunosensor for carcinoembryonic antigen (CEA) determination. Under the optimized conditions, the linear range of the proposed immunosensor is estimated to be from 50fg/mL to 100ng/mL and the detection limit is estimated to be 0.5fg/mL at a signal-to-noise ratio of 3, respectively. The prepared immunosensor for detection of CEA shows high sensitivity, reproducibility and stability. Our study demonstrates that the proposed immunosensor has also been used to determine CEA successfully in diluted blood samples. [Copyright &y& Elsevier]

• An enzyme-free sandwich-type electrochemical sensor for glucose detection was fabricated based on boronate complex. • Three-dimensional self-assembly monolayer was formed above uniformly dispersed gold nanoparticles array. • Electrochemical signals were not from faradic process of glucose oxidation but the secondary receptor FcBA. • The strategy exhibited excellent selectivity, wide linear range and low detection limit for glucose detection. • The proposed method showed promising prospection for glucose test in urine samples in psychological condition. In this article, a sandwich-type electrochemical sensor for selective determination of glucose based on the formation of glucose-boronic bidentate complex has been developed. 3-aminophenylboronic acid (m -APBA) was immobilized on the gold nanoparticles modified ITO electrode with the linker molecule 4-mercaptobenzoic acid (p -MBA). Then, glucose was captured by boronic acid group from m -APBA as the primary receptor and further grafted with an electroactive ferroceneboronic acid (FcBA) as the secondary receptor to form the sandwich-type sensor for selective detection of glucose. For comprehensively understanding the effect of the charge and structure of the terminal boronic acid group of 3-APBA on its binding to glucose, surface p K a was studied by electrochemical titration method, and it was proved the feasibility of examining glucose in physiological condition by the sandwich-type electrochemical sensor. The electrochemical characteristics of the as-prepared sensor were investigated by using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical sensor displayed a linear detection range of glucose from 0.5 mmol L−1 to 30 mmol L−1, with detection limit of 43 µmol L−1. The sensor exhibited good performance in selectivity study with the coexistence of galactose, fructose, mannose and other common interferences in physiological environment, such as, uric acid, ascorbic acid and dopamine. The as-prepared electrode with high sensitivity, good stability and reproducibility as well as excellent biocompatibility made it promising for the development of enzyme-free sensors. [ABSTRACT FROM AUTHOR]

Gives information on the difficulty of solving problems completely about electronic configuration assignments of atomic energy levels. Information on artificial neural networks (ANNs); Details of experiments; Results and conclusions of experiments.

The diamondback moth Plutella xylostella is a major destructive pest of Brassica worldwide. P. xylostella has evolved resistance to nearly all commercial insecticides used for its control, including the most recent chemical class, diamide insecticides. Several studies show that the G4946E and I4790M mutations of ryanodine receptor (RyR) are strongly associated with diamide resistance in insects. While the pivotal functional role of G4946E in conferring diamide resistance phenotype has confirmed by several studies in different species, no direct evidence has unambiguously confirmed the functional significance of the single I4790M mutation in diamide resistance. Here, we successfully constructed a knockin homozygous strain (I4790M-KI) of P. xylostella using CRISPR/Cas9 coupled with homology directed repair approach to introduce I4790M into RyR. When compared with the background susceptible IPP-S strain, the manipulated I4790M-KI strain exhibited moderate resistance to the phthalic acid diamide flubendiamide (40.5-fold) and low resistance to anthranilic diamides chlorantraniliprole (6.0-fold) and cyantraniliprole (7.7-fold), with no changes to the toxicities of indoxacarb and β-cypermethrin. Furthermore, the acquired flubendiamide resistance was inherited in an autosomally recessive mode and significantly linked with the I4790M mutation of RyR in this I4790M-KI strain. Our findings provide in vivo functional evidence for the causality of I4790M mutation of PxRyR with moderate levels of resistance to flubendiamide in P. xylostella , and support the hypothesis that the diamide classes have different interactions with RyRs. Image 1 • RyR I4790M mutation was introduced in P. xylostella with CRISPR/Cas9 editing. • The I4790M mutation knockin strain confers unequal resistance to diamides. • The acquired flubendiamide resistance was autosomal and recessive. • The flubendiamide resistance was genetically linked with the I4790M mutation. [ABSTRACT FROM AUTHOR]

A new fluorescence turn-on probe for Hg2+imaging in living cells was judiciously designed based on the interactions of Hg2+to both thiol and alkyne moieties in a rhodamine scaffold, and the likely novel sensing mechanism has been proposed. [ABSTRACT FROM AUTHOR]

Cao, X.; Li, X.; Yue, F., and Sun, H., 2020. Research and application of vibration measurement while drilling in the undersea coal mine. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 323–327. Coconut Creek (Florida), ISSN 0749-0208. In order to solve the problem of fine detection of complex geological structure in the mining process of undersea coal mine, the method of vibration measurement while drilling is put forward to realize the automatic and effective identification of lithology. In order to determine the feasibility of the method of vibration measurement while drilling on different engineering conditions, the time domain and frequency domain signals under different drilling conditions were analyzed. The various working conditions, such as static drill pipe, artificial drill pipe, rotated unbroken rock and rotated broken rock, were determined by the time domain signals collected from undersea coal mine. Combined with variance analysis, time-consuming analysis and high frequency signal in frequency domain in rock breaking time, the changes in frequency domain signals of different lithology during drilling and rock breaking are determined, thus determining the position of lithological changes during the drilling process. The method of vibration measurement while drilling provides technical guarantee for fine geological detection. [ABSTRACT FROM AUTHOR]

The taxonomic impediment is characterized by dwindling classical taxonomic expertise, and slow pace of revisionary work, thus more rapid taxonomic assessments are needed. Here we pair rapid DNA barcoding methods with swift assessment of morphology in an effort to gauge diversity, establish species limits, and rapidly disseminate taxonomic information prior to completion of formal taxonomic revisions. We focus on a poorly studied, but diverse spider genus, Pseudopoda, from East Asia. We augmented the standard barcoding locus (COI) with nuclear DNA sequence data (ITS2) and analyzed congruence among datasets and species delimitation methods for a total of 572 individuals representing 23 described species and many potentially new species. Our results suggest that a combination of CO1 + ITS2 fragments identify and diagnose species better than the mitochondrial barcodes alone, and that certain tree based methods yield considerably higher diversity estimates than the distance-based approaches and morphology. Combined, through an extensive field survey, we detect a twofold increase in species diversity in the surveyed area, at 42-45, with most species representing short range endemics. Our study demonstrates the power of biodiversity assessments and swift dissemination of taxonomic data through rapid inventory, and through a combination of morphological and multi-locus DNA barcoding diagnoses of diverse arthropod lineages. [ABSTRACT FROM AUTHOR]

In this communication, for the first time, an easy preparation method of nickel–iron (Ni–Fe) hybrid nanocubes for glucose oxidation, which is highly efficient in alkaline media, is described. As an impressive redox probe for glucose, the Ni–Fe hybrid nanocubes exhibit many remarkable sensing performances, for example, low-response time (7 s), broad detection range (from 10 μM to 20.5 mM), and low detection limit (0.64 μM, S/N = 3). The selectivity, reliability and stability of the Ni–Fe hybrid nanocubes for glucose oxidation are also investigated. The glucose sensor based on Ni–Fe hybrid nanocubes shows a superior sensing performance to that of Ni-based or Fe-based electrochemical sensors. Furthermore, the Ni–Fe hybrid nanocubes were used to detect glucose in real samples of human blood serum. All the findings demonstrate that the glucose sensor based on Ni–Fe hybrid nanocubes is successful for glucose detection and shows promise for future applications in medical diagnostics, the food industry and biological processes. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged as a novel pathogen in 2019. The virus is responsible for a severe acute respiratory syndrome outbreak, affecting the respiratory system of infected individuals. COVID-19 is a super amplifier of basic diseases, and the disease with basic diseases is often more serious. Controlling the spread of the COVID-19 pandemic relies heavily on the timely and accurate detection of the virus. To resolve the problem, a polyaniline functionalized NiFeP nanosheet array-based electrochemical immunosensor using Au/Cu2O nanocubes as a signal amplifier is fabricated for the detection of SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 NP). Polyaniline (PANI) functionalized NiFeP nanosheet arrays are synthesized as an ideal sensing platform for the first time. PANI is coated on the surface of NiFeP by electropolymerization to enhance biocompatibility, beneficial for the efficient loading of the capture antibody (Ab1). Significantly, Au/Cu2O nanocubes possess excellent peroxidase-like activity and exhibit outstanding catalytic activity for the reduction of H2O2. Therefore, Au/Cu2O nanocubes combine with a labeled antibody (Ab2) through the Au–N bond to form labeled probes, which can effectively amplify current signals. Under optimal conditions, the immunosensor for the detection of SARS-CoV-2 NP shows a wide linear range of 10 fg mL−1–20 ng mL−1 and a low detection limit of 1.12 fg mL−1 (S/N = 3). It also exhibits desirable selectivity, repeatability, and stability. Meanwhile, the excellent analytical performance in human serum samples confirms the practicality of the PANI functionalized NiFeP nanosheet array-based immunosensor. The electrochemical immunosensor based on the Au/Cu2O nanocubes as a signal amplifier demonstrates great potential for application in the personalized point-of-care (POC) clinical diagnosis. [ABSTRACT FROM AUTHOR]

Detection of tumor biomarkers is of great significance for early diagnosis of cancer. Herein, we fabricated a novel lab-on-a chip surface-enhanced Raman scattering (SERS) (LoC-SERS) biosensing platform for highly sensitive and specific detection of thrombin and platelet-derived growth factor-B (PDGF-B) using aptamer recognition technology. This strategy relies on the specific aptamer recognition between SERS probes (Ag–Au core–shell nanorods (Ag–AuNRs) modified with Raman reporter molecules and detection aptamer) and SERS capture substrate (Au nanoflower (AuNF) substrates modified with capture aptamer), which significantly amplify the plasmonic coupling effect that allows the ultrasensitive and high specificity SERS detection. The limits of detection (LODs) are as low as 3.62 fM for thrombin and 2.86 fM for PDGF-B. Such LoC-SERS platform is further employed to simultaneously detect two types of gastric carcinoma-related with high sensitivity and specificity, which meanwhile exhibit robust capacity of resisting disturbance in practical samples. The results revealed that the present LoC-SERS platform displayed excellent analytical performance, including superior reproducibility, specificity, and sensitivity. Satisfactory results were obtained in real sample analysis with the LoC-SERS platform. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) based on the doubleantibody sandwich format is reported for the determination of carcinoembryonic antigen. Ordered gold nanobowl arrays were fabricated and conjugated with anticarcinoembryonic as capturing substrates, and gold nanoshells, adsorbed with 4-mercaptobenzonic acid, were modified with anticarcinoembryonic antigen as labeling tags. After the carcinoembryonic antigen was captured on ordered gold nanobowl arrays, the labeling tags were bonded to the captured carcinoembryonic antigen. The interaction of SERS substrates (ordered gold nanobowl arrays) and SERS labels (gold nanoshells) showed high sensitivity and a low detection limit for carcinoembryonic antigen. The linear dynamic range of SERS for carcinoembryonic antigen was from 5 pg/mL to 100 ng/mL with a linear relationship between carcinoembryonic antigen concentration and SERS intensity. The detection limit was 1.73 pg/mL. SERS detection may be used for other cancer biomarkers and provides potential for the clinical diagnosis of cancer biomarkers. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) based on the double-antibody sandwich format is reported for the determination of carcinoembryonic antigen. Ordered gold nanobowl arrays were fabricated and conjugated with anticarcinoembryonic as capturing substrates, and gold nanoshells, adsorbed with 4-mercaptobenzonic acid, were modified with anticarcinoembryonic antigen as labeling tags. After the carcinoembryonic antigen was captured on ordered gold nanobowl arrays, the labeling tags were bonded to the captured carcinoembryonic antigen. The interaction of SERS substrates (ordered gold nanobowl arrays) and SERS labels (gold nanoshells) showed high sensitivity and a low detection limit for carcinoembryonic antigen. The linear dynamic range of SERS for carcinoembryonic antigen was from 5 pg/mL to 100 ng/mL with a linear relationship between carcinoembryonic antigen concentration and SERS intensity. The detection limit was 1.73 pg/mL. SERS detection may be used for other cancer biomarkers and provides potential for the clinical diagnosis of cancer biomarkers. [ABSTRACT FROM PUBLISHER]

At the end of 2019, the novel coronavirus disease 2019 (COVID-19), a cluster of atypical pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been known as a highly contagious disease. Herein, we report the MXene/P–BiOCl/Ru(bpy) 3 2+ heterojunction composite to construct an electrochemiluminescence (ECL) immunosensor for SARS-CoV-2 nucleocapsid protein (CoVNP) determination. Two-dimensional (2D) material ultrathin phosphorus-doped bismuth oxychloride (P–BiOCl) is exploited and first applied in ECL. 2D architectures MXene not only act as "soft substrate" to improve the properties of P–BiOCl, but also synergistically work with P–BiOCl. Owing to the inimitable set of bulk and interfacial properties, intrinsic high electrochemical conductivity, hydrophilicity and good biocompatible of 2D/2D MXene/P–BiOCl/Ru(bpy) 3 2+, this as-exploited heterojunction composite is an efficient signal amplifier and co-reaction accelerator in the presence of tri-n-propylamine (TPA) as a coreactant. The proposed MXene/P–BiOCl/Ru(bpy) 3 2+-TPA system exhibits a high and stable ECL signal and achieves ECL emission quenching for "signal on-off" recognition of CoVNP. Fascinatingly, the constructed ECL biosensor towards CoVNP allows a wide linear concentration range from 1 fg/mL to 10 ng/mL and a low limit of detection (LOD) of 0.49 fg/mL (S /N = 3). Furthermore, this presented strategy sheds light on designing a highly efficient ECL nanostructure through the combination of 2D MXene architectures with 2D semiconductor materials in the field of nanomedicine. This ECL biosensor can successfully detect CoVNP in human serum, which can promote the prosperity and development of diagnostic methods of SARS-CoV-2. [Display omitted] • Two-dimensional (2D) material ultrathin P–BiOCl is exploited and first applied in ECL. • 2D architectures MXene act as "soft substrate" to improve the properties of P–BiOCl and synergistically work with P–BiOCl. • MXene/P–BiOCl/ Ru(bpy) 3 2+ is an efficient signal amplifier and co-reaction accelerator in the presence of TPA as a coreactant. • A "signal on-off" ECL biosensor MXene/P–BiOCl/ Ru(bpy) 3 2+/GCE can specifically recognize SARS-CoV-2 nucleocapsid protein. [ABSTRACT FROM AUTHOR]

A novel surface-enhanced Raman scattering and lateral flow assay (SERS–LFA) biosensor with multiple channels based on an aptamer has been proposed in this work. The developed biosensor was designed for the rapid, convenient, sensitive and specific detection of vascular endothelial growth factor (VEGF) and osteopontin (OPN) in several samples simultaneously. During the assay, VEGF and OPN were recognized by detection aptamers immobilized on cuprous oxide nanocubes (Cu2O NCs) and captured by capture aptamers to form a sandwich structure on the test lines. In this way, generous numbers of "hot spots" formed by the aggregation of Cu2O NCs remarkably enhanced the SERS signals of Raman reporters (NBA and 4-ATP). The detection limits were as low as 0.78 pg mL−1 for the VEGF and 0.86 pg mL−1 for OPN in the human serum within 15 min, respectively. Additionally, the biosensor possesses favorable specificity, reproducibility, uniformity and stability. In the clinical analysis of serum specimens, patients with cervical cancer can be differentiated from healthy volunteers. Consequently, the presented aptamer-based SERS–LFA biosensor with multiple channels provides a powerful tool for the early diagnosis of cervical cancer. [ABSTRACT FROM AUTHOR]

In this work, a microfluidic chip using Au@SiO2 array–based highly active SERS substrates was developed for quantitative detection of squamous cell carcinoma antigen (SCCA) and carcinoembryonic antigen (CEA) associated with cervical cancer. The chip consisted of six functional units with pump-free design, enabling parallel detection of multiple samples in an automatic manner without external pumps and improving the portability. Ag nanocubes (AgNCs) were labeled with Raman reporters and coupled with antibodies (labeling) to prepare SERS tags, while the Au nanoparticle–modified SiO2 microsphere (Au@SiO2) array was conjugated with antibodies (coating) to generate the highly SERS-active capturing substrate. In the presence of target biomarkers, they were captured by SERS tags and capturing substrate, resulting in the formation of "sandwich" structures which were trapped in the detection chamber. As the immune reaction proceeded, a large number of "hot spots" were generated by the proximity of the Au@SiO2 array substrate and AgNCs, greatly amplifying SERS signals. With this chip, the limits of detection of the SCCA and CEA levels in human serum were estimated to be as low as 0.45 pg mL−1 and 0.36 pg mL−1, respectively. Furthermore, the good selectivity and reproducibility of this chip were confirmed. Finally, clinical serum samples were analyzed by this chip, and the outcomes were consistent with those of enzyme-linked immunosorbent assay (ELISA). Thus, the proposed microfluidic chip can be potentially applied for the clinical diagnosis of cervical cancer. [ABSTRACT FROM AUTHOR]

With the increasing influence of electromagnetic radiation on precision instruments and organisms, there is an urgent need for research on lightweight and high-strength electromagnetic wave absorbing materials. This study has probed into a new composite absorbing material based on reduced graphene oxide (rGO)-NiMnO3, where the like-core-shell NiMnO3 is anchored on the rGO nanosheets to significantly improve the electromagnetic wave dissipation ability of the composite material using the inter-component dipole polarization and interface polarization. At the same time, NiMnO3 can effectively adjust the impedance matching ratio of rGO so that electromagnetic waves can effectively enter the absorbing material. At a thickness of 3.73 mm, the maximum absorption strength of rGO-NiMnO3 reaches −61.4 dB at 6.6 GHz; at a thickness of 2.5 mm, the adequate absorption bandwidth is 10.04–18.00 GHz, achieving a full coverage for the Ku band. As a new option for preparing lightweight and broadband electromagnetic wave absorbing materials, rGO-NiMnO3 is an ideal material for electromagnetic wave protection. [ABSTRACT FROM AUTHOR]

Cervical cancer is a common cause of cancer-related death in women worldwide, and quantitative detection of serum tumor markers has practical implications for diagnosing cervical cancer. In this study, a novel surface-enhanced Raman scattering (SERS)-based immunosensor for the hypersensitive simultaneous detection of survivin and osteopontin (OPN) in cervical cancer serum was proposed, which was composed of the AuNPs@SiO2 microspheres (Au@SiO2) array immunosubstrate and Au-Ag nanoshells (Au-AgNSs) immunoprobes. The experimental results demonstrated that the constructed SERS immunosensor exhibited satisfactory selectivity and reproducibility while possessing detection limits as low as 0.908 pg/mL and 0.813 pg/mL for survivin and OPN in human serum. Finally, its usefulness in real serum samples (from healthy subjects, cervical intraepithelial neoplasia 1 (CIN 1), CIN 2, CIN 3 and cervical cancer patients) was verified, and the detection data were in good agreement with the enzyme-linked immunosorbent assay results. This immunosensor has excellent performance, which is promising for the early screening of cancer. The ordered single-layer gold film and monolayer SiO2 array were obtained by the oil–water interface self-assembly method and Langmuir-Blodgett (LB) gas–liquid interface assembly method, respectively. Then, these two ordered structures are combined to prepare Au@SiO2 array substrates. This ordered array substrate not only ensures good uniformity, but also improves SERS performance. [ABSTRACT FROM AUTHOR]

Small G protein Ras induces the activation of apoptosis-related molecule mammalian Ste20-like kinase1 (MST1)/JNK signal pathway, which is involved in the regulation of tissue damage under pathological conditions such as ischemic stroke. Our previous study indicated that GTPase-activating protein for Ras (SynGAP), a negative regulator of Ras, could bind with postsynaptic density protein-93 (PSD-93) and Tat-SynGAP (670–685aa) small peptide to exhibit neuroprotective role. Here, we report that Tat-SynGAP (670–685aa) reduced cerebral edema at acute cerebral ischemia/reperfusion (I/R), improved integrity of blood-brain barrier, and decreased cortical and striatum neuronal injury. Mechanistically, Tat-SynGAP (670–685aa) not only inhibited the phosphorylation of MST1 and JNK and the cleavage of caspase-3, but also facilitated the expression of angiogenesis related molecules VEGF and Ang-1. In conclusion, Tat-SynGAP (670–685aa) reduces neuronal apoptosis and cerebral infarction volume and maintains vascular stability and blood-brain barrier integrity by inhibiting MST1/JNK signaling pathway. • Tat-SynGAP improves stroke recovery via inhibiting binding of PSD-93 and SynGAP. • Tat-SynGAP maintains vascular stability and blood-brain barrier integrity. • Tat-SynGAP performs neuroprotective effect by disturbing MST1/JNK signal pathway. [ABSTRACT FROM AUTHOR]

Research methods for DNA detection have been widely extended since the application of nanotechnology, but it remains a challenge to detect specific DNA sequences or low abundance genes in biological samples with accuracy and sensitivity. Herein, a novel biosensor is proposed for the analysis of target DNA in maize based on a high-density "hot spot" surface-enhanced Raman scattering (SERS) substrate and hybridization chain reaction (HCR) amplification strategy. Finite-difference time-domain (FDTD) simulation confirmed that the electromagnetic field enhancement at the gaps between the adjacent Au nanoflowers (AuNFs) was much richer than that around a single AuNF, indicating that the aggregated AuNFs had a good SERS signal amplification effect. Based on the high-density "hot spots" AuNF substrate, the HCR of biotin-hairpin DNA (bio-H1 and bio-H2) could be triggered by the existence of target DNA and a long double-stranded DNA (dsDNA) could be formed rapidly. Due to the biotin and streptavidin (SA) interaction, SERS probes prepared by modifying biotin-DNA-cyanine 5 (bio-DNA-Cy5) on the surface of Ag–Au core–shell nanorods (Ag–AuNRs) could be assembled along the dsDNA, causing significant signal enhancement. The developed biosensor displayed a significant sensitivity with a broad detection range covering from 0.01 to 1 × 104 fM, and the limit of detection (LOD) was as low as 6.31 aM. Moreover, SERS was applied to detect target DNA in maize extract to verify the feasibility of the detection strategy. This strategy could not only carry out the ultrasensitive detection of target DNA but also provide an informative supplement to the SERS biosensing platform. [ABSTRACT FROM AUTHOR]

Abstract: We have successfully introduced a novel strategy for the rational design of a fluorescence turn-on probe for iodide, which is a notorious fluorescence quencher due to the heavy atom effect. The strategy is based on the redox reaction between Cu2+ and iodide. The probe exhibited a 20-fold fluorescence enhancement in the presence of 4equiv. of iodide. The probe developed herein represents the first fluorescence amplified probe for iodide. We believe that it will find interesting use in environment. [Copyright &y& Elsevier]

Abstract: The sensitivity as well as dynamic range of a ratiometric probe is determined by the ratio of emission intensities at two wavelengths. Thus, it is highly desirable to acquire a large ratiometric fluorescence response at two wavelengths. However, ratiometric fluorescent signals are intrinsic characteristics of the particular probe–analyte interactions. The design for fluorescent probes with a large ratiometric signal remains a challenging task. There is still a lack of a proper approach to enhance the ratiometric fluorescence response for fluorescent chemodosimeters. Herein, we introduced a novel strategy to increase the emission ratios of a chemodosimeter via modulation of intramolecular charge transfer. [Copyright &y& Elsevier]

Main observation and conclusion: Accurate determination of acetaminophen concentration is essential for studying the metabolic status of acetaminophen in clinical practice. In this study, nickel phosphide was used for electrochemical detection of acetaminophen for the first time. An electrochemical acetaminophen sensor based on Ni2P nanosheets was successfully constructed and the sensor showed many convincing properties: (a) a good linear range (0.5 μmol/L—4.5 mmol/L); (b) a moderate sensitivity (131.1 μA·mmol–1·L·cm–2); (c) a low detection limit (0.107 μmol/L). In addition, the sensor also showed excellent selectivity, robust stability and reliable repeatability. Further experiments demonstrate that the prepared sensor can be used for quantitative detection of acetaminophen in commercial medical drugs. [ABSTRACT FROM AUTHOR]

Post‐synaptic density 93 (PSD‐93) mediates glutamate excitotoxicity induced by ischemic brain injury, which then induces microglial inflammatory response. However, the underlying mechanisms of how PSD‐93 mediates the crosstalk between neurons and microglia in the post‐synaptic dense region remain elusive. CX3 chemokine ligand 1 (CX3CL1) is a chemokine specifically expressed in neurons while its receptor CX3CR1 is highly expressed in microglia. In this study, we examined the interaction of PSD‐93 and CX3CL1 in the crosstalk between neurons and microglia in acute ischemic stroke. We utilized male C57BL/6 mice to establish the middle cerebral artery occlusion model (MCAO) and designed a fusion small peptide Tat‐CX3CL1 (357‐395aa) to inhibit PSD‐93 and CX3CL1 interaction. The combination peaks of PSD‐93 and CX3CL1 at 6 hr after I/R were observed. The binding sites were located at the 420–535 amino acid sequence of PSD‐93 and 357–395 amino acid sequence of CX3CL1. Tat‐CX3CL1 (357‐395aa) could inhibit the interaction of PSD‐93 and CX3CL1 and inhibited the pro‐inflammatory cytokine IL‐1β and TNF‐α expression and provided neuroprotection following reperfusion. Together, these data suggest that PSD‐93 binds CX3CL1 to activate microglia and initiate neuroinflammation. Specific blockade of PSD‐93‐CX3CL1 interaction reduces I/R induced neuronal cell death, and provides a new therapeutic target for ischemic stroke. [ABSTRACT FROM AUTHOR]

The detection of dopamine is essential for the treatment and diagnosis of depression and other diseases. In this work, cobalt phosphide nanowire arrays grown on titanium mesh (CoP NWAs/TM) are prepared by two steps of hydrothermal and phosphating, and firstly used for the detection of dopamine. The electrochemical behavior of the CoP NWAs/TM was evaluated by amperometry and differential pulse voltammetry. Amperometric analysis reveals admirable parameters in neutral PBS: (a) a working potential of 0.30 V; (b) a wide linear range (1 μM ~ 3 mM); (c) a high sensitivity (3366 μA·mM−1·cm−2); (d) a low detection limit (3.56 × 10–4 mM). Moreover, the interference effect of the common interfering species and the stability were investigated. Further experiments show that the sensor could be successfully used to detect dopamine in human blood serum. Highly sensitive and selective dopamine sensor uses three-dimensional cobalt phosphide nanowire array, which is the first experiment to apply Co-based transition metal phosphides for dopamine detection. The sensor based on cobalt phosphide nanowire array-electrode could be successfully used to detect dopamine in human blood serum. [ABSTRACT FROM AUTHOR]

Sea ice conditions and navigability along four typical routes of the Northeast Passage (NEP) are analysed using remote-sensing data from 1979 to 2019. The influence of air temperature (Tair) and surface wind on the sea ice concentration (SIC) and the navigability of routes is determined. It is found that the annually averaged SICs of the different routes have decreased over the past 41 years. The fastest rate of decrease occurred in the Kara Sea (∼−1% per year), while the slowest rates of decrease occurred in the Laptev/East Siberian Sea (∼−0.42% per year). The number of navigable days for the Kara Sea has become ∼1–2 months longer than the Laptev/East Siberian Sea route as a result. The effect of Tair on SIC, quantified by ΔSIC/ΔTair in the routes through the eastern Kara Sea and Laptev/East Siberian Sea in 2010s was ∼−0.04/°C, two to three times that seen during the 1980s. Air temperature is becoming a significant driving force of melting ice in these routes. Surface winds are also a crucial factor for the navigability of the Vilkitsky Strait and Long Strait, as they drive ice drift, and affect the navigability of the Kara Strait by introducing warm air. [ABSTRACT FROM AUTHOR]

Enterocytozoon hepatopenaei (EHP) is a prevalent microsporidian pathogen responsible for hepatopancreatic microsporidiosis (HPM) in Litopenaeus vannamei. This infection not only leads to slowed growth in shrimp abut aslo inflicts substantial economic losses in the global aquaculture industry. However, the molecular mechanisms by which EHP influences the host during various infection stages remain unclear. This study employed comparative transcriptomics to examine the effects of EHP infection on Litopenaeus vannamei between early and late stage of infection groups. Utilizing transcriptomic approaches, we identified differentially expressed genes (DEGs) with notable biological significance through the COG, GO, KEGG, GSEA, and Mufzz time-series methodologies. The results reveal that EHP infection considerably influences host gene expression, with marked differences between early and late infection across distinct timeframes. Key processes such as detoxification, cell apoptosis, and lipid metabolism are pivotal during host-parasite interactions. Hexokinase and phosphatidic acid phosphatase emerge as key factors enabling invasion and sustained effects. Cytochrome P450 and glucose-6-phosphate dehydrogenase could facilitate infection progression. EHP significantly impacts growth, especially through ecdysteroids and 17β-estradiol dehydrogenase. By delineating stage-specific effects, we gain insights into interaction between EHP and Litopenaeus vannamei, showing how intracellular pathogens reprogram host defenses into mechanisms enabling long-term persistence. This study provides a deeper understanding of host-pathogen dynamics, emphasizing the interplay between detoxification, metabolism, immunity, apoptosis and growth regulation over the course of long-term symbiosis. As the duration of EHP infection increased, shrimp were subjected to changes in each of the main effects. PCA analysis was used to assess inter-sample group variability versus intra-sample group reproducibility. Venn diagrams of DEGs in Asn vs Asp, Jsn vs Jsp, Asn vs Jsn, and Asp vs Jsp. Distribution of KEGG pathway enrichment. The results of GSEA analysis for Asn vs Asp, Jsn vs Jsp groups. [Display omitted] • EHP infection influences host gene expression between early and late infection stages. • Detoxification, cell apoptosis and lipid metabolism are pivotal in host-parasite interactions. • Hexokinase and phosphatase enable invasion and prolonged effects through key roles. • Cytochrome P450 and G6PD facilitate infection progression. • EHP affects growth, particularly through ecdysteroids and 17β-HSD. [ABSTRACT FROM AUTHOR]

There is a challenge to obtain an ultrasensitive and rapid approach to detect bacteria and identify resistance. As a powerful bioanalytical tool, surface-enhanced Raman scattering (SERS) in bacterial detection have attracted increasing attentions. Herein, we developed a SERS-active Au@Ag core-shell nanorod (Au@AgNR) tag platform for ultrasensitive bacteria detection and antibiotic-susceptibility testing (AST). The platform established that surface enhanced Raman scattered Rhodamine 6G (R6G) absorption at 1517 cm−1 had a good linearity (RI = 3865 + 193logC; R2 = 0.97) with logarithm of E. coli concentration over a range of 107–102 CFU (colony forming unit)/mL with limit of detection as low 102 CFU/mL. When E. coli was exposed to ampicillin at minimum inhibitory concentration (MIC, 4 μg/mL), Raman spectroscopy showed the obvious variation between ampicillin-susceptible E. coli (Amp−- E. coli) and the ampicillin-resistant E. coli (Amp+- E. coli). Combined with principal component analysis (PCA) statistical analysis, the Raman intensity variation mentioned above allows to obtain rapid antibiotic resistance testing (<3.5 h). In addition, E.coli spiked into blood from C57BL/6 mice can be identified clearly, indicating the potential for point-of-care diagnostics. Image 1 • Ultrasensitive and rapid approach to detect bacteria and identify resistance. • SERS nanotags can specifically anchor onto E.coli. • Raman intensity collected from the SERS nanotags bound E. coli is proportional to logarithm of E. coli concentration. • Combined with PCA, the Raman intensity statistical analysis allows to obtain rapid antibiotic resistance testing. [ABSTRACT FROM AUTHOR]

A CoNi-based metal–organic framework (CoNi-MOF) nanosheet array is synthesized by the treatment of a CoNi layered double hydroxide nanosheet array on Ni foam with 3,5-diaminobenzoic acid. The CoNi-MOF nanosheet array with amino and carboxyl groups can be used to capture the human chorionic gonadotropin (HCG) primary antibody (HCG Ab1). Nile Blue decorated ZnNi-MOF (NB@ZnNi-MOF) spheres immobilized with HCG secondary antibodies (HCG Ab2) are used for signal amplification. When HCG exists in an analytical sample, a sandwich structure is formed and an electrochemical signal is produced. The analytical signal generated during the detection is caused by the conversion of Co(II) and Co(III) in the CoNi-MOF nanosheet array. The Nile Blue of the NB@ZnNi-MOF sphere, as a kind of redox-active species, is responsible for the electrochemical signal amplification in the immunosensor. On the basis of the above advantages, the HCG immunosensor exhibits a lower limit of detection (1.85 × 10−3 mIU mL−1) and a wide linear range from 0.005 mIU mL−1 to 250 mIU mL−1. Additionally, this immunosensor is used to quantitatively detect HCG in human blood serum and shows good correlations with the standard enzyme-linked immunosorbent assay (ELISA), providing a high value on clinical diagnosis. [ABSTRACT FROM AUTHOR]

The electrode design is of considerable importance for developing enhanced electrochemical sensing platforms. Conductive metal–organic frameworks (MOFs), with high surface area, high conductivity, and large pore volume, possess an ideal architecture for the detection of molecules. In this study, we report the first electro-oxidation of glucose in an alkaline solution using conductive Ni-based metal–organic framework nanosheet arrays on carbon cloth (Ni-MOF NSAs/CC) as a non-noble metal catalyst. Compared with a number of ligands coordinated to nickel salt, 2,3,6,7,10,11-hexaaminotriphenylene hexahydrochloride was selected as the best ligand to synthesize Ni-MOF because it has the highest electrocatalytic activity for glucose oxidation. The 3D Ni-MOF NSAs/CC electrode, as multifunctional sensors, was used to detect glucose with a low detection limit of 0.57 μM (S/N = 3), a wide linear range of 0.001–7 mM, high sensitivity of 13428.89 μA mM−1 cm−2, and good selectivity. The results demonstrate that the as-prepared Ni-MOF NSAs/CC has considerable development and application potential for clinical medical testing. [ABSTRACT FROM AUTHOR]

Detecting microRNA (miRNA) biomarkers expression is of great significance for the diagnosis and treatment of lung cancer. Surface-enhanced Raman scattering (SERS) has achieved microRNA sensing for the diagnosis of primary liver cancers. In this work, we developed a SERS technology for the rapid detection of lung cancers-related miRNA (miR-196a) using bimetallic Au-Ag nanowire (AgNW@AuNPs) substrates coupled with the target hairpin DNA. The finite-difference time-domain simulation proved that a large number of "hot spots" were generated between the AgNW and AuNPs, which resulted in a huge enhancement of the signal of Raman reporters. Filter paper treated by hexadecenyl succinic anhydride hydrophobic and modified with AgNWs@AuNPs was used as capturing substrate. The detection limits of miR-196a in PBS and serum were as low as 96.58 aM and 130 aM, respectively. Studies on nonspecific sequence and single-base mismatch of miRNA demonstrated that SERS-based platform was highly selective, excellent uniform, and reproducible. Finally, the platform was used to show that the miR-196a expression in the serum of lung cancer patients was much higher than that in healthy people. The detection results indicated that the SERS platform had potential applications in cancer diagnosis and might be a viable alternative to the conventional miRNA detection method, the real-time polymerase chain reaction (RT-PCR) technology. [ABSTRACT FROM AUTHOR]

The high incidence of premature rupture of membranes (PROM) is closely related to the lack of screening methods. Herein, a rapid and sensitive detection model for procalcitonin (PCT) and interleukin-6 (IL-6) was established utilizing the principle of antigen antibody binding and combined with surface enhanced Raman spectroscopy (SERS) and immunochromatographic assay (ICA), which could be used for the detection of specific biomarkers at a low concentration of peripheral blood and early detection of PROM patients. 5,5′-Dithiobis-2-nitrobenzoic acid labeled monoclonal anti-IL-6 on gold nanocages (GNCs) and 4-methylthiobenzoic acid labeled monoclonal anti-PCT on GNCs were employed as SERS tags. In the presence of IL-6 and PCT, the antigen-SERS tag complexes were trapped and concentrated on the two test lines. The unique characteristics of GNCs with hollow and multi-branch angle allowed high SERS performance in the system by increasing the biological binding sites and hot spots. Through finite difference time domain simulation, it could be concluded that the electromagnetic field between the gaps of GNC dimers was stronger than that of the single GNC, which proved the feasibility of ICA based on surface enhanced Raman scattering (SERS-ICA) in theory. The detection limits of IL-6 and PCT in phosphate buffer were 7.897 pg mL−1 and 7.725 pg mL−1, meanwhile the detection limits of peripheral blood were 8.414 pg mL−1 and 8.017 pg mL−1, respectively. In addition, the detection of real-world samples showed that SERS-ICA was available to evaluate the concentrations of IL-6 and PCT. The experimental data of SERS-ICA were in accordance with that of enzyme-linked immunosorbent assay. These results indicated that SERS-ICA had great potential in the early screening of PROM. [ABSTRACT FROM AUTHOR]

Ultrasensitive detection of specific biomarkers in clinical serum is helpful for early diagnosis of cervical cancer. In this paper, a surface-enhanced Raman scattering (SERS)-based immunoassay was developed for the simultaneous determination of squamous cell carcinoma antigen (SCCA) and osteopontin (OPN) in cervical cancer serum. Au-Ag nanoshuttles (Au-AgNSs) as SERS tags and hydrophobic filter paper-based Au nanoflowers (AuNFs) as capture substrate were constructed into a sandwich structure which served as an ultrasensitive SERS-based immunoassay platform. Finite difference time domain simulation confirmed that the electromagnetic field coupled between the AuNFs had a prominent SERS signal enhancement effect, which improved the detection sensitivity. SERS mapping showed that hexadecenyl succinic anhydride hydrophobic treatment could prevent the analyte from being quickly absorbed by the filter paper and increase the retention time to be more evenly distributed on the filter paper substrate. The immunoassay platform was verified to have good selectivity and reproducibility. With this method, the detection limits of SCCA and OPN in human serum were as low as 8.628 pg/mL and 4.388 pg/mL, respectively. Finally, in order to verify the feasibility of its clinical application, the serum samples of healthy subjects; cervical intraepithelial neoplasia I (CINI), CINII, and CINIII; and cervical cancer patients were analyzed, and the reliability of the results was confirmed by enzyme-linked immunosorbent assay experiments. The constructed SERS-based immunoassay platform could be used as a clinical tool for early screening of cancers in the future. [ABSTRACT FROM AUTHOR]

A sensor for the determination of guanine (G) and hydrogen peroxide (H 2 O 2) is developed based on Ni–Fe Prussian blue analogues hollow nanocubes (Ni–Fe PBA HNCs) for the first time. As a remarkable redox probe towards G and H 2 O 2 oxidation, Ni–Fe PBA HNCs exhibit a series of predominant sensing performances as follows: lower limit of detection, broader linear range and higher selectivity due to the homogeneous hollow structure, high specific surface and the enhanced electron transfer ability of Ni–Fe PBA HNCs. As a G sensor, it exhibits a wide linear range (0.05–4.0 mM) and a low detection limit of 0.0104 μM (S/N = 3). As a H 2 O 2 sensor, the Ni–Fe PBA HNCs show superior sensing performances with a low detection limit of 0.291 μM (S/N = 3) and a wide detection range of 0.1–20 mM. By cause of these advantages, the real-time detection of G and H 2 O 2 in human saliva are triumphantly accomplishment, indicating the applicability of Ni–Fe PBA HNCs. Image 1 • A sensor for the determination of guanine and hydrogen peroxide is developed based on Ni-Fe Prussian blue analogues hollow nanocubes for the first time. • As a remarkable redox probe towards guanine and hydrogen peroxide oxidation, the Ni-Fe hollow nanocubes exhibit a series of predominant sensing performances. • The real-time detection of H 2 O 2 in human saliva is triumphantly accomplishment, indicating the applicability of Ni-Fe hollow nanocubes. [ABSTRACT FROM AUTHOR]

Variations in the intracellular expression level of cancer-related microRNAs (miRNAs) are connected with worsening tumor progression. A simple, accurate, and sensitive analytical method for the imaging and detection of intracellular miRNA is still a great challenge due to the low abundance of miRNAs and the complexity of intracellular environments. In this work, target miRNA (miRNA)-mediated catalytic hairpin assembly (CHA)-induced gold nanocage (GNC)-hairpin DNA1 (hpDNA1)-hpDNA2-GNC nanostructures were designed for surface-enhanced Raman scattering (SERS) detection and imaging of the specific miR-125a-5p in the normal lung epithelial cell line (BEAS-2B cells) and lung cancer cell line (A549 cells). The finite difference time domain (FDTD) simulations showed that the polymer of GNCs possessed a much stronger electromagnetic field in nanogaps than that of single GNC, theoretically confirming the rational design of the CHA assembly strategy. Using this method, miR-125a-5p can be detected in a wide linear range with a detection limit of 43.96 aM and high selectivity over other miRNAs in vitro. Moreover, SERS imaging successfully detected and distinguished the expression levels of intracellular miR-125a-5p in BEAS-2B cells and A549 cells. The results obtained by the SERS assay were consistent with those obtained by the real-time quantitative polymerase chain reaction (qRT-PCR). This method can offer a powerful strategy for the imaging and quantitative detection of various types of biomolecules in vitro as well as in living cells. [ABSTRACT FROM AUTHOR]