Publications by authors named "Shuyan Xue"

8 Publications

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Spatio-temporal evolution and influencing mechanism of the COVID-19 epidemic in Shandong province, China.

Sci Rep 2021 04 9;11(1):7811. Epub 2021 Apr 9.

College of Urban and Environmental Sciences, Northwest University, Xi'an, 710127, China.

The novel coronavirus pneumonia (COVID-19) outbreak that emerged in late 2019 has posed a severe threat to human health and social and economic development, and thus has become a major public health crisis affecting the world. The spread of COVID-19 in population and regions is a typical geographical process, which is worth discussing from the geographical perspective. This paper focuses on Shandong province, which has a high incidence, though the first Chinese confirmed case was reported from Hubei province. Based on the data of reported confirmed cases and the detailed information of cases collected manually, we used text analysis, mathematical statistics and spatial analysis to reveal the demographic characteristics of confirmed cases and the spatio-temporal evolution process of the epidemic, and to explore the comprehensive mechanism of epidemic evolution and prevention and control. The results show that: (1) the incidence rate of COVID-19 in Shandong is 0.76/100,000. The majority of confirmed cases are old and middle-aged people who are infected by the intra-province diffusion, followed by young and middle-aged people who are infected outside the province. (2) Up to February 5, the number of daily confirmed cases shows a trend of "rapid increase before slowing down", among which, the changes of age and gender are closely related to population migration, epidemic characteristics and intervention measures. (3) Affected by the regional economy and population, the spatial distribution of the confirmed cases is obviously unbalanced, with the cluster pattern of "high-low" and "low-high". (4) The evolution of the migration pattern, affected by the geographical location of Wuhan and Chinese traditional culture, is dominated by "cross-provincial" and "intra-provincial" direct flow, and generally shows the trend of "southwest → northeast". Finally, combined with the targeted countermeasures of "source-flow-sink", the comprehensive mechanism of COVID-19 epidemic evolution and prevention and control in Shandong is revealed. External and internal prevention and control measures are also figured out.
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http://dx.doi.org/10.1038/s41598-021-86188-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8035406PMC
April 2021

Copper- and Cobalt-Codoped CeO Nanospheres with Abundant Oxygen Vacancies as Highly Efficient Electrocatalysts for Dual-Mode Electrochemical Sensing of MicroRNA.

Anal Chem 2019 02 1;91(4):2659-2666. Epub 2019 Feb 1.

Laboratory of Advanced Materials, Department of Materials Science and Collaborative Innovation Center of Chemistry for Energy Materials (iChem) , Fudan University , Shanghai 200438 , PR China.

Oxide materials with redox properties have aroused growing interest in many applications. Introducing dopants into crystal lattices provides an effective way to optimize the catalytic activities of the oxides as well as their redox properties. Herein, CeO nanospheres codoped with Cu and Co (CuCo-CeO NSs) were first synthesized and exploited as efficient electrocatalysts for dual-mode electrochemical sensing of microRNA (miRNA). With the doping of Cu and Co into the CeO lattice, large amounts of extra oxygen vacancies were generated, remarkably enhancing the redox and electrocatalytic properties of the CeO material. The abundant oxygen vacancies of the CuCo-CeO NSs were further identified by X-ray photoelectron spectroscopy (XPS), H temperature-programmed reduction (H-TPR), and electron-energy-loss spectroscopy (EELS). Moreover, Mg-induced DNAzyme-assisted target recycling was introduced for ultrasensitive determination. The dual-mode sensing with generality was conducted as follows: First, the CuCo-CeO NSs acted as a direct redox mediator to generate a differential-pulse-voltammetry (DPV) signal, which was then greatly amplified by the efficient electrocatalysis of CuCo-CeO NSs toward HO decomposition. Second, under the electrocatalysis of CuCo-CeO NSs, 3,3-diaminobenzidine (DAB) was oxidized to form nonconductive insoluble precipitates (IPs), leading to great amplification of the electrochemical-impedimetric-spectroscopy (EIS) signal. The dual-mode electrochemical sensor showed a wide linear range (0.1 fM to 10 nM) with a low detection limit (33 aM), paving a new way for constructing ultrasensitive electrochemical sensors.
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http://dx.doi.org/10.1021/acs.analchem.8b03778DOI Listing
February 2019

Glucose oxidase-initiated cascade catalysis for sensitive impedimetric aptasensor based on metal-organic frameworks functionalized with Pt nanoparticles and hemin/G-quadruplex as mimicking peroxidases.

Biosens Bioelectron 2017 Dec 20;98:83-90. Epub 2017 Jun 20.

Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China. Electronic address:

Based on cascade catalysis amplification driven by glucose oxidase (GOx), a sensitive electrochemical impedimetric aptasensor for protein (carcinoembryonic antigen, CEA as tested model) was proposed by using Cu-based metal-organic frameworks functionalized with Pt nanoparticles, aptamer, hemin and GOx (Pt@CuMOFs-hGq-GOx). CEA aptamer loaded onto Pt@CuMOFs was bound with hemin to form hemin@G-quadruplex (hGq) with mimicking peroxidase activity. Through sandwich-type reaction of target CEA and CEA aptamers (Apt1 and Apt2), the obtained Pt@CuMOFs-hGq-GOx as signal transduction probes (STPs) was captured to the modified electrode interface. When 3,3-diaminobenzidine (DAB) and glucose were introduced, the cascade reaction was initiated by GOx to catalyze the oxidation of glucose, in situ generating HO. Simultaneously, the decomposition of the generated HO was greatly promoted by Pt@CuMOFs and hGq as synergistic peroxide catalysts, accompanying with the significant oxidation process of DAB and the formation of nonconductive insoluble precipitates (IPs). As a result, the electron transfer in the resultant sensing interface was effectively hindered and the electrochemical impedimetric signal (EIS) was efficiently amplified. Thus, the high sensitivity of the proposed CEA aptasensor was successfully improved with 0.023pgmL, which may be promising and potential in assaying certain clinical disease related to CEA.
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http://dx.doi.org/10.1016/j.bios.2017.06.039DOI Listing
December 2017

Dendritic structure DNA for specific metal ion biosensor based on catalytic hairpin assembly and a sensitive synergistic amplification strategy.

Biosens Bioelectron 2017 Jan 12;87:157-163. Epub 2016 Aug 12.

Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 PR China. Electronic address:

In this work, a sensitive electrochemical biosensing to Pb was proposed based on the high specificity of DNAzymes to Pb. The response signal was efficiently amplified by the catalytic hairpin assembly induced by strand replacement reaction and the formation of dendritic structure DNA (DSDNA) by layer-by-layer assembly. Firstly, in the presence of Pb, the substrate strand (S1) of the Pb-specific DNAzymes was specifically cleaved by Pb. Secondly, one of the two fragments (rS1) introduced into the electrode surface was hybridized with a hairpin DNA (H1) and further replaced by another hairpin DNA (H2) by the hybridization reaction of H1 with H2. The released rS1 then induced the next hybridization with H1. After repeated cycles, the catalytic recycling assembly of H2 with H1 was completed. Thirdly, two bioconjugates of Pt@Pd nanocages (Pt@PdNCs) labeled with DNA S3/S4 and electroactive toluidine blue (Tb) (Tb-S3-Pt@PdNCs and Tb-S4-Pt@PdNCs) were captured onto the resultant electrode surface through the hybridization of S3 and H2, S3 and S4, resulting in the formation of DSDNA triggered by layer-by-layer assembly. This formed DSDNA greatly facilitated the immobilization of manganese(III) meso-tetrakis (4-N-methylpyridiniumyl)-porphyrin (MnTMPyP) as mimicking enzyme. Under the synergistic catalysis of Pt@PdNCs and MnTMPyP to HO reduction, the effective signal amplification of the developed Pb biosensor was achieved. As a result, the sensitive detection of the proposed electrochemical strategy for Pb was greatly improved in the range of 0.1pM-200nM with a detection limit of 0.033pM.
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http://dx.doi.org/10.1016/j.bios.2016.08.032DOI Listing
January 2017

Hemin on graphene nanosheets functionalized with flower-like MnO2 and hollow AuPd for the electrochemical sensing lead ion based on the specific DNAzyme.

Biosens Bioelectron 2016 Dec 30;86:958-965. Epub 2016 Jul 30.

Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China. Electronic address:

Herein, integrated with DNAzyme highly specific to metal ions, hemin@reduced graphene oxide (hemin@rGO) functionalized with flower-like MnO2 and hollow AuPd (hAuPd-fMnO2-hemin@rGO) was used as electroactive probe and electrocatalyst to construct a universal platform for metal ion detection (lead ion Pb(2+) as the model). The proposed strategy with generality was mainly based on two aspects. Firstly, the designed probe not only showed high stability and excellent peroxidase-like activity originating from hemin, fMnO2 and hAuPd, but also possessed intrinsic redox performance from hemin, which resulted in the promotion of electron transfer and the enhancement of the response signal readout. Secondly, due to the introduction of Pb(2+), Pb(2+)-dependent DNAzyme bound in the electrode surface could be specifically identified and cleaved by Pb(2+), and the remained fragment (its supplementary sequence is a single-strand DNA S3) captured the nanocomposites S3-hAuPd-fMnO2-hemin@rGO by the hybridization reaction. Therefore, combined the cooperative catalysis of fMnO2, hAuPd and hemin to H2O2 reduction with highly specific interaction of Pb(2+)-dependent DNAzyme, the proposed Pb(2+) biosensor showed significant improvement of electrochemical analytical performance, which was involved in wide dynamic response in the range of 0.1pM-200nM, low detection limit of 0.034pM, high sensitivity and high specificity. This could facilitate the universal strategy to be a promising method for detection of other metal ions, only changing the corresponding DNAzyme specific to them.
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http://dx.doi.org/10.1016/j.bios.2016.07.111DOI Listing
December 2016

A sensitive impedimetric platform biosensing protein: Insoluble precipitates based on the biocatalysis of manganese(III) meso-tetrakis (4-N-methylpyridiniumyl)-porphyrinin in HCR-assisted dsDNA.

Biosens Bioelectron 2016 Dec 20;86:656-663. Epub 2016 Jul 20.

Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715 PR China. Electronic address:

In this study, a sensitive biosensing interface for protein was reported based on nonconductive insoluble precipitates (IPs) by the biocatalysis of manganese(III) meso-tetrakis (4-N-methylpyridiniumyl)-porphyrin (MnTMPyP), which was intercalated into formed double-strand DNA (dsDNA) scaffold triggered by hybridization chain reaction (HCR). In the proposed impedimetric aptasensor, carcinoembryonic antigen (CEA) and its aptamer were used as testing model. PtPd nanowires (PtPdNWs) with large surface area and superior conductivity were employed as nanocarriers to greatly immobilize biomolecules (e.g. CEA aptamers). Then, two DNA hairpins H1 and H2 were introduced to trigger HCR with the assistance of DNA initiator, resulting in the formation of a long dsDNA scaffold. Meanwhile, mimicking enzyme MnTMPyP molecules were embedded into the resultant dsDNA, in situ generating the complex MnTMPyP-dsDNA with peroxidase-like activity. Under the biocatalysis of MnTMPyP-dsDNA, 3,3-diaminobenzidine (DAB) was oxidized to form nonconductive IPs. As a result, the electron transfer between electrode interface and redox probe was vastly hindered, leading to the significant amplification of electrochemical impedimetric signal. So, greatly improved analytical performances of the proposed aptasensor were achieved with a detection limit as low as 0.030pgmL(-1). And the successful assay of CEA in human serum samples enabled the developed biosensing platform to have promising potential in bioanalysis.
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http://dx.doi.org/10.1016/j.bios.2016.07.065DOI Listing
December 2016

A sensitive electrochemical aptasensor based on the co-catalysis of hemin/G-quadruplex, platinum nanoparticles and flower-like MnO2 nanosphere functionalized multi-walled carbon nanotubes.

Chem Commun (Camb) 2015 Jan;51(8):1472-4

Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P. R. China.

In this work, a sensitive electrochemical aptasensor for the detection of thrombin (TB) is developed and demonstrated based on the co-catalysis of hemin/G-quadruplex, platinum nanoparticles (PtNPs) and flower-like MnO2 nanosphere functionalized multi-walled carbon nanotubes (MWCNT-MnO2).
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http://dx.doi.org/10.1039/c4cc08860cDOI Listing
January 2015

A sensitive electrochemical aptasensor based on palladium nanoparticles decorated graphene-molybdenum disulfide flower-like nanocomposites and enzymatic signal amplification.

Anal Chim Acta 2015 Jan 13;853:234-241. Epub 2014 Oct 13.

Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education (Southwest University), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China. Electronic address:

In the present study, with the aggregated advantages of graphene and molybdenum disulfide (MoS2), we prepared poly(diallyldimethylammonium chloride)-graphene/molybdenum disulfide (PDDA-G-MoS2) nanocomposites with flower-like structure, large surface area and excellent conductivity. Furthermore, an advanced sandwich-type electrochemical assay for sensitive detection of thrombin (TB) was fabricated using palladium nanoparticles decorated PDDA-G-MoS2 (PdNPs/PDDA-G-MoS2) as nanocarriers, which were functionalized by hemin/G-quadruplex, glucose oxidase (GOD), and toluidine blue (Tb) as redox probes. The signal amplification strategy was achieved as follows: Firstly, the immobilized GOD could effectively catalyze the oxidation of glucose to gluconolactone, coupling with the reduction of the dissolved oxygen to H2O2. Then, both PdNPs and hemin/G-quadruplex acting as hydrogen peroxide (HRP)-mimicking enzyme could further catalyze the reduction of H2O2, resulting in significant electrochemical signal amplification. So the proposed aptasensor showed high sensitivity with a wide dynamic linear range of 0.0001 to 40 nM and a relatively low detection limit of 0.062 pM for TB determination. The strategy showed huge potential of application in protein detection and disease diagnosis.
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http://dx.doi.org/10.1016/j.aca.2014.10.003DOI Listing
January 2015