Publications by authors named "Xia Lian"

72 Publications

A novel ratiometric fluorescence nanoprobe for sensitive determination of uric acid based on [email protected] nanocomposites.

Mikrochim Acta 2021 Jul 16;188(8):259. Epub 2021 Jul 16.

Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, Shandong, 266042, People's Republic of China.

A novel ratiometric fluorescence nanoprobe based on carbon dots (CDs) and Cu nanoclusters (CuNCs) was designed for the label-free determination of uric acid (UA). The metal-organic framework (MOF) encapsulated CuNCs (ZIF-CuNC), and nitrogen-doped CDs can self-assemble into well-defined spherical nanocomposites ([email protected]) due to physical adsorption. Under the excitation wavelength of 360 nm, the [email protected] nanocomposites exhibit two evident intrinsic emissions peaked at 460 nm (CDs) and 620 nm (ZIF-CuNC), respectively. In the presence of HO, the fluorescence of [email protected] at 620 nm is quenched remarkably within 1 min, while little effect on the emission at 460 nm is observed. Therefore, taking the fluorescence at 620 nm as the report signal and 460 nm as the reference signal, ratiometric quantitative determination of HO was achieved with a linear range of 1-100 μM and a detection limit of 0.30 μM. The [email protected] nanoprobe was successfully applied to the determination of UA that is catalyzed by uricase to produce HO, obtaining the linear range of 1-30 μM and the detection limit of 0.33 μM. Eventually, this strategy has been successfully applied to the determination of UA in human urine samples. A novel and convenient [email protected] nanoplatform was constructed for sensitive ratiometric fluorescence determination of UA.
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http://dx.doi.org/10.1007/s00604-021-04914-xDOI Listing
July 2021

The GLP-1/GIP dual-receptor agonist DA5-CH inhibits the NF-κB inflammatory pathway in the MPTP mouse model of Parkinson's disease more effectively than the GLP-1 single-receptor agonist NLY01.

Brain Behav 2021 Jun 14. Epub 2021 Jun 14.

Second Hospital, Neurology Department, Shanxi Medical University, Taiyuan, Shanxi Province, People's Republic of China.

The GLP-1 receptor agonist exendin-4 has recently shown good effects in a phase II clinical trial in Parkinson's disease (PD) patients. Here, a comparison of the new GLP-1/GIP dual receptor agonist DA5-CH and NLY01, a 40 kDa pegylated form of exendin-4, on motor impairments and reducing inflammation in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) PD mouse model is provided. The drug groups received either DA5-CH or NLY01 (25 nmol/kg) i.p. after daily MPTP intraperitoneal injection. Both drugs showed improvements in motor activity, open field experiments, rotarod tests, and gait analysis, but DA5-CH was more potent. Tyrosine hydroxylase expression in dopaminergic neurons was much reduced by MPTP and improved by DA5-CH, while NLY01 showed weak effects. When analyzing levels of α-synuclein (α-Syn), DA5-CH reduced levels effectively while NLY01 had no effect. When measuring the levels of the inflammation markers Toll-like receptor 4 (TLR4), specific markers of microglia activation (Iba-1), the marker of astrocyte activation glial fibrillary acidic protein (GFAP), nuclear factor-κB (NF-κB), tumor necrosis factor (TNF-α), and transforming growth factor β1 (TGF-β1), DA5-CH was very effective in reducing the chronic inflammation response, while NLY01 did not show significant effects. Levels of key growth factors such as Glial cell-derived neurotrophic factor (GDNF) and Brain-derived neurotrophic factor (BDNF) were much reduced by MPTP, and DA5-CH was able to normalize levels in the brain, while NLY01 showed little effect. The levels of pro-inflammatory cytokines (IL-6 and IL-Iβ) were much reduced by DA5-CH, too, while NLY01 showed no effect. In a separate experiment, we tested the ability of the two drugs to cross the blood-brain barrier. After injecting fluorescin-labelled peptides peripherally, the fluorescence in brain tissue was measured. It was found that the pegylated NLY01 peptide did not cross the BBB in meaningful quantities while exendin-4 and the dual agonist DA5-CH did. The results show that DA5-CH shows promise as a therapeutic drug for PD.
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http://dx.doi.org/10.1002/brb3.2231DOI Listing
June 2021

Naphthalimide Derivative-Functionalized Metal-Organic Framework for Highly Sensitive and Selective Determination of Aldehyde by Space Confinement-Induced Sensitivity Enhancement Effect.

Anal Chem 2021 06 2;93(23):8219-8227. Epub 2021 Jun 2.

Chemistry and Chemical Engineering College, Qufu Normal University, Qufu 273165, PR China.

Facile and sensitive determination of formaldehyde (FA) in indoor environments still remains challenging. Herein, a fluorescent probe, termed [email protected], was synthesized by embedding the fluorescent molecule of -propyl-4-hydrazine-naphthalimide (PHN) into a metal-organic framework (MOF) for sensitive and visual monitoring of FA. The hydrazine group of PHN acts as the specific reaction group with FA based on the condensation reaction. The host of MOF (UiO-66-NH) offers the surrounding confinement space required for the reaction. Owing to the enrichment effect and molecular sieve selection of UiO-66-NH to FA, [email protected], compared with free PHN, exhibits very high sensitivity and selectivity based on space confinement-induced sensitivity enhancement (SCISE). Moreover, the fluorescence of UiO-66-NH offers a reference signal for FA detection. Using this ratiometric fluorescent [email protected] probe, a colorimetric gel plate and test paper were developed and used to visually monitor FA in air.
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http://dx.doi.org/10.1021/acs.analchem.1c00916DOI Listing
June 2021

Needle tract seeding of papillary thyroid carcinoma after fine-needle capillary biopsy: A case report.

World J Clin Cases 2021 May;9(15):3662-3667

Department of Head and Neck Surgery, Affiliated Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang Province, China.

Background: Fine-needle biopsy is an accurate and cost-efficient tool for the assessment of thyroid nodules. It includes two primary methods: Fine-needle capillary biopsy (FNCB) and fine-needle aspiration biopsy. Needle tract seeding (NTS) is a rare complication of thyroid fine-needle biopsy mainly caused by fine-needle aspiration biopsy rather than FNCB. Here, we present an extremely rare case of a papillary thyroid carcinoma (PTC) patient with FNCB-derived NTS.

Case Summary: We report a 32-year-old woman with PTC who showed subcutaneous NTS 1 year after FNCB and thyroidectomy. NTS was diagnosed based on clinical manifestations, biochemistry indices, and imaging (computed tomography and ultrasound). Pathological identification of PTC metastases consistent with the puncture path is the gold standard for diagnosis. Surgical resection was the main method used to treat the disease. After surgery, thyroid function tests and ultrasound scans were performed every 3-6 mo. To date, no evidence of tumor recurrence has been observed.

Conclusion: FNCB is a safe procedure as NTS is rare, and can be easily removed surgically with no recurrence. Accordingly, NTS should not limit the usefulness of FNCB.
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http://dx.doi.org/10.12998/wjcc.v9.i15.3662DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8130087PMC
May 2021

The effect of the area proportion of the metastatic lesion within the central metastatic lymph node on response to therapy in papillary thyroid carcinoma.

Oncol Lett 2021 Apr 12;21(4):284. Epub 2021 Feb 12.

Department of Head and Neck Surgery, Affiliated Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Zhejiang, Hangzhou 310016, P.R. China.

Lymph node (LN) metastasis has been strongly associated with locoregional recurrence and decreased survival time of patients with papillary thyroid carcinoma (PTC). Although the characteristics of the metastatic LNs (mLN) have been determined, including size, number, micro-metastasis and extra-nodal extension (ENE), further analysis is warranted. The present study introduced a new parameter known as the area proportion of the metastatic lesion within the central mLNs (APmCLN). The objective was to evaluate the impact of the APmCLN on response to therapy in patients with PTC. In total, 355 patients with PTC treated with total thyroidectomy and neck dissection, post-operative radioactive iodine and thyroid-stimulating hormone suppression were retrospectively studied. The patients were classified into two groups: Group A (APmCLN ≤75%) and group B (APmCLN >75%). The association of various clinicopathological characteristics between these two groups was investigated. Univariate and multivariate analyses were used to evaluate risk factors associated with a non-Excellent response to therapy and recurrence-free survival (RFS). The analysis showed that APmCLN >75% was significantly associated with extra-thyroidal extension, clinically apparent nodes (cN1), pathological N1b (pN1b), ENE, greater number and larger size of central mLN and larger size of the central LN metastatic lesion. Furthermore, it was reported that chronic lymphocytic thyroiditis, larger central mLN size and APmCLN >75% were independent risk factors for a non-excellent response to therapy. Finally, it was determined that the rate of excellent response to therapy was significantly higher in pathological N1 (pN1) patients with APmCLN ≤75% (108/144, 75.0%) compared with patients with APmCLN >75% (27/47, 57.4%) (P=0.022). However, there was no significant difference (P=0.247) between patients with APmCLN ≤75% and pN0 (132/164, 80.5%). RFS was 89.4% in patients with pN1-APmCLN >75%, whereas those with pN1-APmCLN ≤75% and pN0 did not experience a relapse. Patients with PTC with APmCLN >75% should be regarded as high-risk and may require more aggressive treatment and careful follow-up.
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http://dx.doi.org/10.3892/ol.2021.12545DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7905529PMC
April 2021

Diabetes Care During COVID-19 Pandemic in Singapore Using a Telehealth Strategy.

Horm Metab Res 2021 Mar 2;53(3):191-196. Epub 2021 Feb 2.

Department of Endocrinology, Tan Tock Seng Hospital, Singapore.

Singapore currently has one of highest number of confirmed COVID-19 cases in Southeast Asia. To curb the further spread of COVID-19, Singapore government announced a temporary nationwide lockdown (circuit breaker). In view of restrictions of patients' mobility and the enforcement of safe distancing measures, usual in-person visits were discouraged. Here we describe how diabetes care delivery was ad hoc redesigned applying a telehealth strategy. We describe a retrospective assessment of subjects with diabetes, with and without COVID-19 infection, during the circuit breaker period of 7th April to 1st June 2020 managed through Tan Tock Seng Hospital's telehealth platform. The virtual health applications consisted of telephone consultations, video telehealth visits via smartphones, and remote patient monitoring. The TTSH team intensively managed 298 diabetes patients using a telehealth strategy. The group comprised of (1) 84 inpatient COVID-19 patients with diabetes who received virtual diabetes education and blood glucose management during their hospitalisation and follow-up via phone calls after discharge and (2) 214 (n=192 non-COVID; n=22 COVID-positive) outpatient subjects with suboptimal glycaemic control who received intensive diabetes care through telehealth approaches. Remote continuous glucose monitoring was applied in 80 patients to facilitate treatment adjustment and hypoglycaemia prevention. The COVID-19 pandemic situation mooted an immediate disruptive transformation of healthcare processes. Virtual health applications were found to be safe, effective and efficient to replace current in-person visits.
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http://dx.doi.org/10.1055/a-1352-5023DOI Listing
March 2021

In-situ synthesis of 3D [email protected] MOF nanobelt arrays with improved conductivity for sensitive photoelectrochemical detection of vascular endothelial growth factor 165.

Biosens Bioelectron 2020 Nov 3;167:112481. Epub 2020 Aug 3.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu Shandong, 273165, PR China. Electronic address:

Construction of novel photoelectrochemical (PEC) materials with unique structures can effectively improve the photoelectric conversion efficiency. Here, a self-supported [email protected]/copper mesh (CM) nanobelt arrays with high specific surface area, high orientation, and high photoelectric conversion performance is obtained by in-situ grown strategy. Such PEC aptasensor is constructed based on the [email protected]/CM combined with rolling circle amplification and enzymatic biocatalytic precipitation for vascular endothelial growth factor 165 analysis. This strategy achieves excellent cooperative signal amplification, which greatly improves the detection sensitivity. The PEC aptasensor exhibited a wide calibration ranged from 10 to 1 × 10 fM with a detection limit down to 2.3 fM (S/N = 3). The construction of [email protected] has developed the potential application of MOFs in photoelectrochemical and found a reliable path for ultrasensitive detection of biomarkers.
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http://dx.doi.org/10.1016/j.bios.2020.112481DOI Listing
November 2020

Adaptive robust servo constraint tracking control for an underactuated quadrotor UAV with mismatched uncertainties.

ISA Trans 2020 Nov 7;106:12-30. Epub 2020 Jul 7.

National Engineering Laboratory for Highway Maintenance Equipment, Chang'an University, Xi'an, Shanxi 710065, PR China; The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA. Electronic address:

In this research, to achieve the altitude and attitude tracking control of an underactuated quadrotor UAV with mismatched uncertainties, based upon Udwadia-Kalaba theory, a novel adaptive robust tracking control approach is proposed and which will be designed in two steps. First, aiming at the uncertain and underactuated quadrotor UAV, regardless of initial constraint deviation and mismatched uncertainties, a nominal control is constructed through transforming the desired trajectories into corresponding servo constraints; second, for the mismatched uncertainties, we decompose them into two parts, i.e. the matched part and mismatched part, and the mismatched part will "vanish" during the stability analysis of proposed adaptive robust controller. Eventually, with such a decomposition technique, the large mismatched uncertainties can be addressed properly and the burden of controller design will be reduced to a certain degree. In addition, two deterministic robust control performances are also guaranteed by our proposed approach. The simulation results have shown a good robustness and tracking precision of our proposed scheme for quadrotor UAV.
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http://dx.doi.org/10.1016/j.isatra.2020.07.007DOI Listing
November 2020

Impact of Vitamin E supplementation on vascular function in haptoglobin genotype stratified diabetes patients (EVAS Trial): a randomised controlled trial.

Nutr Diabetes 2020 04 27;10(1):13. Epub 2020 Apr 27.

Tan Tock Seng Hospital, Singapore, Singapore.

Aims: Vitamin E (Vit-E) may preferentially improve cardiovascular risk in haptoglobin 2-2 (Hp2-2) genotype diabetes individuals. We studied the impact of Vit-E supplementation on vascular function in diabetes individuals stratified by haptoglobin genotype in Singapore.

Methods: In this 24-week, double blind, placebo-controlled RCT, we recruited 187 subjects (101 Hp2-2, 86 non-Hp2-2).

Intervention: alpha-tocopherol-400 IU.

Primary Outcome: Change in EndoPAT-derived reactive-hyperaemia index (RHI) and augmentation index (AIx); Secondary Outcomes: Pulse-Wave velocity (Sphygmocor-PWV), carotid intima media thickness (CIMT), inflammation (hsCRP), derivatives of reactive-oxygen metabolites (dROMs), biological antioxidant-potential (BAPs), HbA1c, LDL-C, HDL-C and oxidised LDL-C (ox-LDL).

Results: Overall, with Vit-E supplementation no significant change in RHI, PWV, CIMT, hsCRP, dROMS, BAPs, HDL-C and HbA1c was observed (p > 0.05); an increase in LDL-C with concomitant decrease in ox-LDL, and incidentally increase in eGFR was observed (p < 0.05). No interaction effect with haptoglobin genotype was seen for all outcomes (p > 0.05). Subgroup analysis: In the non-Hp-2-2 group, Vit-E supplementation led to a higher EndoPAT-derived AIx, accompanied by higher LDL and ox-LDL concentrations (p < 0.05); Hp2-2 group: Vit-E supplementation led to higher eGFR when compared to the non-Hp2-2 group (exploratory) (p < 0.05). We observed an interaction effect for baseline haptoglobin concentration (threshold > 119 mg/dl) with intervention in terms of increased EndoPAT-derived AIx in the Hp > 119 mg/dl group whereas no change in the group with Hp ≤ 119 mg/dl.

Conclusion: Vit-E supplementation did not show any preferential benefit or deleterious effect on vascular function in Hp2-2 diabetes subjects in Singapore. A possible deleterious effect of an increase in arterial stiffness in individuals with Hp > 119 mg/dl was observed. Future studies should consider personalisation based on baseline Hp concentrations in patients with T2DM rather than just Hp2-2 genotype to evaluate impact on the detailed lipid pathways, cardiac and renal physiology. The impact of ethnic differences needs to be explored in greater details.
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http://dx.doi.org/10.1038/s41387-020-0116-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7186220PMC
April 2020

o-Phenylenediamine/gold nanocluster-based nanoplatform for ratiometric fluorescence detection of alkaline phosphatase activity.

Talanta 2020 May 21;212:120768. Epub 2020 Jan 21.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu Shandong, 273165, PR China. Electronic address:

This study demonstrates a novel and convenient ratiometric fluorescent method for the detection of alkaline phosphatase (ALP) activity. Amino-functionalized mesoporous silica nanoparticle-gold nanoclusters (MSN-AuNCs) nanocomposites were integrated with o-phenylenediamine (OPD) to form a ratiometric fluorescence nanoplatform. The presence of ALP induced the generation of quinoxaline (QX) derivative which called 3-(dihydroxyethyl)furo[3,4-b]quinoxaline-1-one (DFQ) with strong fluorescence emission at 450 nm, while the orange-red fluorescence of MSN-AuNCs at 580 nm was slightly quenched. Meanwhile, an obvious fluorescence color change from orange-red to purple and finally to blue can be observed by naked eyes with the increasing of ALP concentration. Therefore, employing the fluorescence emission of DFQ at 450 nm as the reporter signal and the fluorescence emission of MSN-AuNCs at 580 nm as a reference signal, a sensitive ratiometric detection method for ALP was developed. Quantitative detection of ALP activity in the linear range from 0.2 to 80 U/L with a detection limit of 0.1 U/L can be realized in this way, which endows the assay with high sensitivity enough for practical detection of ALP in human serum samples.
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http://dx.doi.org/10.1016/j.talanta.2020.120768DOI Listing
May 2020

Adsorption behavior of a metal organic framework of University in Oslo 67 and its application to the extraction of sulfonamides in meat samples.

J Chromatogr A 2020 May 5;1619:460949. Epub 2020 Feb 5.

Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165, PR China; School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, PR China.

In this work, a dispersive solid phase extraction (d-SPE) method for sulfonamides (SAs) has been developed using a stable and mesoporous metal organic framework (University in Oslo 67, UiO-67) as adsorbent, which was synthesized by coordination of Zr ions with 4, 4-biphenyl-dicarboxylicacid (HBPDC) through a facile one-pot method. Owing to the synergistic effects of π-π interaction, hydrogen bonding, hydrophobic interaction and size match between SAs and the adsorbent, the extraction performance of UiO-67 for SAs was obviously improved. The adsorption behavior, evaluated by the kinetic models, showed that the intraparticle diffusion was involved during the adsorption process. The proper match between the pore size of UiO-67 (3.49 nm) and the molecular sizes of SAs (1.1 nm × 0.65 nm) not only allowed SAs to diffuse intraparticle but also permitted them to adjust their configurations to form hydrogen bonding with the UiO-67. By combination with HPLC analysis, a simple, sensitive, accurate and precise method for detection of SAs has been established. The method proposed in this work showed good performances, including wide linearity (14.6-250 ng/g) with high correlation coefficients (R ≥ 0.9991), low limits of detection (LODs, 0.7-6.5 ng/g for all SAs), satisfactory precision (Intra-day RSDs ≤ 3.4%, inter-day RSDs ≤ 4.7%), and high accuracy (recovery: 83.4-103.8%). Furthermore, benefiting from the mesoporous structure and the Zr cluster center as well as the stability, UiO-67 shows great potential to be an excellent adsorbent of SPE for extraction of SAs from other complex matrices.
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http://dx.doi.org/10.1016/j.chroma.2020.460949DOI Listing
May 2020

Colorimetric detection of Hg(ii) based on the gold amalgam-triggered reductase mimetic activity in aqueous solution by employing [email protected] nanoparticles.

Analyst 2020 Feb;145(4):1362-1367

Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165, China.

Although the potential of gold amalgam as a nanoenzyme has been demonstrated, its practical utility has been limited by its low catalytic activity caused by the aggregation of Au nanoparticles (Au NPs). Thus, there is a need to further engineer Au NPs to prevent aggregation and then to achieve higher enzyme activities for the detection of Hg2+ ions. Metal organic frameworks (MOFs), as one kind of promising material, have attracted particular attention due to their unique characteristics of uniform cavities and very high porosity. Herein, a hybrid material of Au nanoparticles and a MOF ([email protected]), constructed by immobilization of Au NPs uniformly on the cavity surface of an iron-5,10,15,20-tetrakis (4-carboxyl)-21H,23H-porphyrin-based MOF (Fe-TCPP-MOF), has been successfully synthesized. Based on Hg2+ ion triggered Au catalysis of methylene blue (MB) reduction, a colorimetric method for highly sensitive and selective detection of Hg2+ ions has been established. The Hg2+ ions were first bound to the Au NP surface to form gold amalgam, and then the catalytic activity of Au NPs was initiated. This detection method showed the advantages of a fast response time, and high sensitivity and selectivity. The response time and the limit of detection were as low as 2 s and 103 pM, respectively, benefiting from the uniform cavities and the large specific surface area of Fe-TCPP-MOF, which ensure: (1) uniform dispersion of the Au NPs on the surface of the cavity; and (2) a higher chance of interaction of mercury and MB owing to the gathering effect of Fe-TCPP-MOF.
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http://dx.doi.org/10.1039/c9an02615kDOI Listing
February 2020

A Boric Acid-Functionalized Lanthanide Metal-Organic Framework as a Fluorescence "Turn-on" Probe for Selective Monitoring of Hg and CHHg

Anal Chem 2020 02 7;92(4):3366-3372. Epub 2020 Feb 7.

Key Laboratory of Life-Organic Analysis of Shandong Province , Qufu Normal University , Qufu , P.R. China.

Mercury detection remains an important task because of its high toxicity. Herein a new dual-signal probe based on a boric acid (BA)-functionalized lanthanide metal-organic framework (BA-Eu-MOF) was developed for the detection of Hg and CHHg ions for the first time. The BA-Eu-MOF was synthesized by coordination of Eu with 5-boronobezene-1, 3-dicarboxylic acid (5-bop) through a one-pot method. The 5-bop ligand not only acted as the "antenna" to sensitize the luminescence of Eu but also provided reaction sites for Hg and CHHg. Owing to the electron-withdrawing effect of the BA group, the "antenna" effect of the ligand was passivating and the BA-Eu-MOF showed weak red emission in water. Upon addition of Hg or CHHg into the system, a transmetalation reaction took place, i.e., BA groups were replaced by Hg or CHHg; therefore, the "antenna" effect of the ligand was triggered, leading to the enhancement of red emission. As Hg or CHHg concentration increased, the red emission was gradually enhanced, and the color change was also observed with the naked eye under 365 nm ultraviolet light. Owing to the porous characteristics and the surface effect of the MOF, as well as the unique transmetalation reaction between the BA group and Hg or CHHg, the developed nanoprobe showed excellent characteristics for simultaneous detection of Hg and CHHg, such as simple preparation, convenient operation, "turn-on" signal output, high sensitivity, and selectivity. The unique features of the BA-Eu-MOF make it an attractive probe for monitoring Hg and CHHg.
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http://dx.doi.org/10.1021/acs.analchem.9b05410DOI Listing
February 2020

The role of l-histidine as molecular tongs: a strategy of grasping Tb using ZIF-8 to design sensors for monitoring an anthrax biomarker on-the-spot.

Chem Sci 2020 Jan 29;11(9):2407-2413. Epub 2020 Jan 29.

Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University Qufu 273165 China

In this study, a novel lanthanide-doped nanoprobe for monitoring dipicolinic acid (DPA), a unique biomarker of , was constructed by coordination of Tb with l-histidine (His) functionalized ZIF-8 ([email protected]). After being functionalized with His, the resultant [email protected] had abundant carboxyl and amino groups, which like tongs help [email protected] "grasp" Tb firmly to form a stable lanthanide-doped nanoparticle ([email protected]/Tb). Owing to the unsaturated coordination of Tb with the amino acid group, the resultant [email protected]/Tb showed reserved response sites of Tb to DPA because of its unique molecular structure. After the [email protected]/Tb coordination with DPA, the intrinsic fluorescence emission of the Tb ions was triggered through energy transfer, leading to bright yellow green luminescence owing to the antenna role of DPA. Benefitting from the His functionalization and the characteristics of ZIF-8, especially the high porosity and large surface area, the developed [email protected]/Tb sensing platform exhibited attractive features as a fluorescent sensor for monitoring DPA such as fast response kinetics (10 s), high sensitivity and selectivity, and being portable, easy to operate, economical and secure. This sensor platform showed a satisfactory linear relationship ( = 0.999) ranging from 0.08 to 10 μmol L and an ultralow limit of detection (LOD) of 0.02 μmol L. This strategy for the design of functionalized MOFs to construct sensing probes and the resultant [email protected]/Tb would provide a potential strategy for the exploitation of other functionalized materials used in other research fields and promising fluorescence platforms for the detection of other targets.
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http://dx.doi.org/10.1039/d0sc00030bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8157567PMC
January 2020

Hg-mediated stabilization of G-triplex based molecular beacon for label-free fluorescence detection of Hg, reduced glutathione, and glutathione reductase activity.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Mar 23;228:117855. Epub 2019 Nov 23.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, PR China.

G-triplexes have been reported recently with the similar function to G-quadruplex that can combine with thioflavin T (ThT) and emit strong fluorescence but easier to be controlled and excited. In this work, we report an Hg-mediated stabilization of G-triplex based functional molecular beacon (G3TMB) sensing system for the label-free detection of Hg, reduced glutathione (GSH), and glutathione reductase (GR) activity. In the presence of Hg, the extended G-triplex sequence containing the "T" bases can form a stable hairpin structure due to the strong interactions of "T-Hg-T", resulting in the locking of G-tracts in the stem of the G3TMB effectively. However, the hairpin structure of the G3TMB can be opened by the introduction of GSH through the stronger "GSH-Hg" interaction. Therefore, by employing the fact that GR can catalyze the reduction of oxidized glutathione (GSSG) into GSH, this concept can be applied to fluorescence "off-on" detection of GR activity, with a linear range of 0.02-30 mU/mL and detection limit of 0.01 mU/mL. This work may expand a new perspective of G-triplex based functional molecular beacon as the label-free fluorescent probes in the detection of small biomolecule and enzyme activity.
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http://dx.doi.org/10.1016/j.saa.2019.117855DOI Listing
March 2020

Luminescent metal organic frameworks with recognition sites for detection of hypochlorite through energy transfer.

Mikrochim Acta 2019 11 4;186(11):740. Epub 2019 Nov 4.

Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu, Shandong, 273165, People's Republic of China.

A luminescent metal organic framework (LMOF) of type UiO-66-NH was chosen for specific and sensitive detection of trace levels of hypochlorite. Hypochlorite causes the quenching of the blue fluorescence of nano-UiO-66-NH (with excitation/emission maxima at 325/430 nm), and this finding forms the basis for a fluorometric assay for hypochlorite. The method overcomes disadvantages of conventional redox-probes which are interfered by oxidants with oxidation capability stronger than that of hypochlorite. Compared with other fluorescent probes for sensing hypochlorite, UiO-66-NH has a comparable detection limit of 0.3 μmol L and a broad linearity relationship in the range of 1-8 μmol L. The probe was successfully applied to the detection of hypochlorite in complex water samples and living Hela cells. Graphical abstract Schematic representation of hypochlorite induced quenching of the blue fluorescence of nano-UiO-66-NH (with excitation/emission maxima at 325/430 nm) through energy transfer. It overcomes disadvantages of conventional redox-probes which are interfered by oxidants with oxidation capability stronger than that of hypochlorite.
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http://dx.doi.org/10.1007/s00604-019-3806-xDOI Listing
November 2019

3D halos assembled from FeO/Au NPs with enhanced catalytic and optical properties.

Nanoscale 2019 Nov 29;11(43):20968-20976. Epub 2019 Oct 29.

Molecular Sciences and Biomedicine Laboratory (MBL), State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering and College of Biology, Aptamer Engineering Center of Hunan Province, Hunan University, Changsha 410082, China. and Institute of Molecular Medicine (IMM), State Key Laboratory of Oncogenes and Related Genes Renji Hospital, Shanghai Jiao Tong University School of Medicine, and College of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China and Department of Chemistry and Department of Physiology and Functional Genomics, Center for Research at the Bio/Nano Interface, Shands Cancer Center, UF Genetics Institute, McKnight Brain Institute, University of Florida, Gainesville, FL 32611-7200, USA.

3D structures assembled from multiple components have attracted increasing research interest based on their enriched functionalities and broadened applications. Here, we report a bottom-up strategy to fabricate 3D halos through the co-assembly of FeO and Au nanoparticles (NPs). Typically, FeO NPs assemble into a 3D core (size around 500 nm) with simultaneous growth of Au NPs on the 3D surface during the assembly process. As a general approach, a variety of 3D halos were fabricated from the co-assembly of FeO and Au NPs of different sizes and shapes. To demonstrate the advantages of these 3D halo structures, their catalytic activity to mimic natural enzymes was investigated. Compared with FeO NP building blocks, enhanced catalytic efficiency was achieved by the 3D halos. In addition, the optical behavior of the 3D halos was simulated using a three-dimensional finite-difference time-domain (3D-FDTD) method. As shown in the results, the 3D halos attached to 90 nm Au NPs could absorb more incident light owing to high electric field intensities, making these structures promising for applications in energy harvesting and detection-related fields.
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http://dx.doi.org/10.1039/c9nr05874eDOI Listing
November 2019

A label-free G-quadruplex-based fluorescence assay for sensitive detection of alkaline phosphatase with the assistance of Cu.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Feb 7;227:117607. Epub 2019 Oct 7.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu Shandong, 273165, PR China. Electronic address:

The level of alkaline phosphate (ALP) is a significant biomarker index in organism. In this work, a label-free and sensitive G-quadruplex fluorescence assay for monitoring ALP activity has been developed with the assistance of Cu based on the competitive binding effect between pyrophosphate (PPi) and G-quadruplex-N-methylmesoporphyrin (G4/NMM) complex to Cu. In the sensing assay, the G4/NMM complex is employed as a signal indicator, while the Cu as a quencher and the PPi as recovery agent as well as the hydrolytic substance for ALP. In details, the fluorescence of the G4/NMM complex was efficiently quenched by introducing Cu due to the proximal carboxylate groups of NMM coordinating with the Cu as well as the unfolding of G-quadruplex by Cu, while the higher affinity between PPi and Cu could lead to the fluorescence recovery. However, in the presence of ALP, the PPi was hydrolyzed to phosphate ions (Pi) which cannot integrate with Cu, resulting in the fluorescence quenching once again. Thus, a simple and facile way to inspect ALP has been exploited. The proposed assay shows a good linear relationship in the range from 0.5 to 100 U/L with the detection limit of 0.3 U/L. Moreover, the fabricated method is succeeded in detecting ALP in human serum samples, indicating the potential as a profitable candidate in biological and biomedical application.
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http://dx.doi.org/10.1016/j.saa.2019.117607DOI Listing
February 2020

A Metal-Organic Framework as Selectivity Regulator for Fe and Ascorbic Acid Detection.

Anal Chem 2019 10 9;91(19):12453-12460. Epub 2019 Sep 9.

Center for Research at Bio/Nano Interface, Department of Chemistry and Department of Physiology and Functional Genomics, Health Cancer Center, UF Genetics Institute and McKnight Brain Institute , University of Florida , Gainesville , Florida 32611-7200 , United States.

Ferric ion (Fe) plays a vital role in cellular homeostasis. However, the detection of Fe with rhodamine B (RhB) has potential problems, such as poor selectivity and low photostability. To address these problems, we rationally designed an [email protected] nanocomposite-based "on-off-on" fluorescent switching nanoprobe for highly sensitive and selective detection of Fe and ascorbic acid. This [email protected] nanoprobe was prepared through a facile one-pot synthesis. Here MOF served as a selectivity regulator for the detection of Fe. By embedding RhB into the porous crystalline MOF, enhanced photostability and fluorescence lifetime of RhB to Fe were achieved. The as-prepared [email protected] was demonstrated to be an ultrasensitive and selective nanoprobe for the detection of Fe in human serum and ascorbic acid in rat brain microdialysate. Furthermore, inner filter effect (IFE) and photoinduced electron transfer (PET) were proposed and discussed to explain the selectivity and sensitivity of RhB to Fe against other interfering substances. Our novel "on-off-on" nanoprobe provides insight into the rational design of MOF-based biosensors for selective and sensitive detection of analytes.
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http://dx.doi.org/10.1021/acs.analchem.9b03143DOI Listing
October 2019

Photoelectrochemical determination of trypsin by using an indium tin oxide electrode modified with a composite prepared from MoS nanosheets and TiO nanorods.

Mikrochim Acta 2019 07 2;186(8):490. Epub 2019 Jul 2.

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165, People's Republic of China.

A photoelectrochemical (PEC) method has been developed for sensitive detection of trypsin. It is based on the use of a composite consisting of MoS nanosheets and TiO nanorods (MoS-TiO). The material has a high specific surface area, superior electrical conductivity, excellent biocompatibility and good band gap matching. The composite was synthesized by a one-pot method using TiO as a template. This results in a uniform distribution of the MoS nanosheets (<5 layers) in the composite. If the composite, placed on an indium tin oxide (ITO) electrode, is coupled to apoferritin, the photocurrent response decreases due to the insulating effect of the protein. Trypsin, in acting as an alkaline protease, decomposes the apoferritin. This results in the recovery of the PEC signal. Attractive features of this PEC method include (a) a superior PEC signal, (b) sensor stability, (c) simple operation, and (d) the lack of any additional modifications of the biosensor. This warrants high sensitivity, reproducibility, repeatability and practicality. The ITO sensor has a linear response in the 1 to 1000 ng·mL trypsin concentration range and a 0.82 ng·mL detection limit. The assay was applied to the determination of trypsin in spiked serum samples and gave satisfactory results. Graphical abstract Schematic presentation of an indium tin oxide (ITO)/MoS-TiO sensor for detecting trypsin. The PEC signal was decreased after immobilization of apoferritin (APO) on the modified ITO. Trypsin catalytically hydrolyzes APO specifically and induces the PEC signal to recover.
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http://dx.doi.org/10.1007/s00604-019-3589-0DOI Listing
July 2019

Next-generation Sequencing Study of Pathogens in Serum from Patients with Febrile Jaundice in Sierra Leone.

Biomed Environ Sci 2019 May;32(5):363-370

National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.

Objective: People in Western Africa suffer greatly from febrile jaundice, which is caused by a variety of pathogens. However, yellow fever virus (YFV) is the only pathogen under surveillance in Sierra Leone owing to the undeveloped medical and public health system there. Most of the results of YFV identification are negative. Elucidation of the pathogen spectrum is required to reduce the prevalence of febrile jaundice.

Methods: In the present study, we used Ion Torrent semiconductor sequencing to profile the pathogen spectrum in archived YFV-negative sera from 96 patients in Sierra Leone who presented with unexplained febrile jaundice.

Results: The most frequently identified sequencing reads belonged to the following pathogens: cytomegalovirus (89.58%), Epstein-Barr virus (55.21%), hepatitis C virus (34.38%), rhinovirus (28.13%), hepatitis A virus (20.83%), coxsackievirus (10.42%), Ebola virus (8.33%), hepatitis E virus (8.33%), lyssavirus (4.17%), leptospirosis (4.17%), chikungunya virus (2.08%), Crimean-Congo hemorrhagic fever virus (1.04%), and hepatitis B virus (1.04%).

Conclusion: The distribution of sequencing reads suggests a broader spectrum of pathogens for consideration in clinical diagnostics and epidemiological surveillance in Sierra Leone.
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http://dx.doi.org/10.3967/bes2019.048DOI Listing
May 2019

Emissions of terbium metal-organic frameworks modulated by dispersive/agglomerated gold nanoparticles for the construction of prostate-specific antigen biosensor.

Anal Bioanal Chem 2019 Jul 14;411(17):3979-3988. Epub 2019 May 14.

Laboratory Animal Center, Chongqing Medical University, Chongqing, 404100, China.

Herein, a universal and multifunctional fluorescence sensor platform is designed by the interaction of aggregation/dispersion gold nanoparticles (AuNPs) with Tb-metal-organic frameworks (Tb-MOFs). It is found that the dispersed AuNPs rather than the aggregated ones can quench effectively the fluorescence of Tb-MOFs, and the quenching process presumably involves the mechanism of inner filter effect (IFE), dynamic quenching effect (DQE), and fluorescence resonance energy transfer (FRET). The different affinities of aptamer and aptamer-target complex toward AuNPs are employed to modulate the fluorescence signal change of Tb-MOFs. As the proof of concept, prostate-specific antigen (PSA), an efficient tumor indicator for prostate cancer, is selected as the target. At first, the PSA aptamer can protect AuNPs against salt-induced aggregation, leading to the fluorescence of Tb-MOFs quenching. Subsequently, upon PSA introduction, the rigid aptamer-PSA complex is formed and cannot stabilize AuNPs in high salt conditions, so the AuNPs aggregate significantly and the fluorescence of Tb-MOFs is restored. The linear range of PSA is achieved from 1 to 100 ng/mL with a detection limit of 0.36 ng/mL. Finally, this method has been validated to be sensitive and specific for PSA in human urine samples. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-019-01883-2DOI Listing
July 2019

Enhanced electrocatalytic activity of water oxidation in an alkaline medium via Fe doping in CoS nanosheets.

Chem Commun (Camb) 2019 Feb;55(17):2469-2472

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.

The development of new electrocatalysts is critical for efficient water electrolysis to produce hydrogen. In this communication, we report a novel electrocatalyst for the oxygen evolution reaction (OER) which is realized via Fe doping in CoS2 nanosheets (Fe-CoS2). This catalyst shows an overpotential of 302 mV for a current density of 10 mA cm-2, 85 mV less than that for CoS2. In addition, Fe-CoS2 also exhibits high catalytic stability.
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http://dx.doi.org/10.1039/c8cc10203aDOI Listing
February 2019

Aggregation-induced emission enhancement of gold nanoclusters triggered by silicon nanoparticles for ratiometric detection of protamine and trypsin.

Anal Chim Acta 2019 Jan 18;1046:170-178. Epub 2018 Sep 18.

The Key Laboratory of Life-Organic Analysis, Qufu Normal University, Qufu, 273165, Shandong, China; Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, Qufu Normal University, Qufu, 273165, Shandong, China; Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, 810001, China.

Metal nanoclusters protected by glutathione (GSH) have attracted a wide attention due to the unique aggregation-induced emission (AIE) feature. However, the "trigger" effects of ethanol, temperature, pH values, and metal ions may restrict the application of these particles. In this work, the amino modified silicon nanoparticles (SiNPs) and GSH-capped gold nanoclusters (GSH-AuNCs) can self-assemble into well-defined spherical particles due to the electrostatic interaction. As a result, the unique aggregation-induced emission enhancement (AIEE) of GSH-AuNCs arises at 570 nm, and the SiNPs keep their own blue fluorescence at 450 nm, so a novel nanohybrid probe ([email protected]) with dual-emission property has been constructed. When protamine is added to [email protected], the cationic protamine can compete with SiNPs and absorb onto the surface of GSH-AuNCs, which inhibits the self-assembly and leads to the fluorescence quenching of GSH-AuNCs; while trypsin can catalyze the hydrolysis of protamine, the self-assembly starts again, producing the AIEE recovery. In the whole process, the SiNPs act as an internal standard and their emission stays constant. By means of the fluorescence intensity ratios I/I, the linear range of protamine is from 0.15 to 3.00 μg mL with the limit of detection (LOD) of 0.07 μg mL, and trypsin shows a linear response in the range from 10 to 100 ng mL with LOD of 4.50 ng mL. Furthermore, this strategy exhibits good sensitivity and selectivity, and has been further validated by applying it for the determination of protamine and trypsin in serum samples.
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http://dx.doi.org/10.1016/j.aca.2018.09.033DOI Listing
January 2019

A ratiometric detection of heparin with high sensitivity based on aggregation-enhanced emission of gold nanoclusters triggered by silicon nanoparticles.

Talanta 2019 Feb 25;193:37-43. Epub 2018 Sep 25.

Laboratory Animal Center, Chongqing Medical University, Chongqing 400016, China. Electronic address:

Heparin (Hep) is a widely applied anticoagulant and the quantification of heparin concentration is pivotal for clinical use. In this work, silicon nanoparticles (SiNPs) modified by the amino groups and glutathione-capped gold nanoclusters (GSH-AuNCs) are able to self-assemble into spherical particle structures via the electrostatic interaction, resulting in the aggregation-enhanced emission (AEE) of GSH-AuNCs. However, Hep, a highly sulfated glycosaminoglycan with much more negative charges, can bind with the SiNPs and inhibit the aggregation. As a result, it causes the AEE quenching of GSH-AuNCs at 570 nm but the SiNPs keep their own blue fluorescence at 450 nm. Thus, the SiNPs can act as an internal reference and the GSH-AuNCs are used as a signal probe in this process. The ratiometric fluorescent signal (I/I) change of the nanohybrid probe is positively correlated with Hep concentrations in the range from 6.44 ng/mL to 96.6 ng/mL with the detection limit of 3.29 ng/mL. As expected, this strategy shows good sensitivity and selectivity, and it is also successfully applied to detect Hep in Hep sodium injection and human serum samples with good recoveries.
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http://dx.doi.org/10.1016/j.talanta.2018.09.098DOI Listing
February 2019

ZrMOF nanoparticles as quenchers to conjugate DNA aptamers for target-induced bioimaging and photodynamic therapy.

Chem Sci 2018 Oct 30;9(38):7505-7509. Epub 2018 Jul 30.

Molecular Science and Biomedicine Laboratory (MBL) , State Key Laboratory of Chemo/Bio-Sensing and Chemometrics , College of Biology , College of Chemistry and Chemical Engineering , Hunan University , Changsha , 410082 , China . Email: ; Email:

Porphyrinic metal-organic framework (MOF) nanoparticles for photodynamic therapy solve the photosensitizer problems of poor solubility, self-quenching and aggregation. However, their low selectivity towards malignant tissues is an obstacle for bioimaging and a bottle-neck to cellular uptake for highly efficient photodynamic therapy of cancer. Here, ZrMOF nanoparticles as quenchers to conjugate DNA aptamers were developed for target-induced bioimaging and photodynamic therapy. A phosphate-terminal aptamer prepared by solid-phase DNA synthesis was anchored on the surface of ZrMOF nanoparticles through strong coordination between phosphate and zirconium. Based on π-π stacking-induced quenching of TAMRA by ZrMOF nanoparticles, target-induced imaging is achieved due to the structural change of the aptamer upon binding with the target. Aptamer-conjugated ZrMOF nanoparticles with target binding ability significantly enhanced the photodynamic therapy effect. Furthermore, phosphate-terminal aptamer conjugation method can be generalized to other types of MOF nanomaterials, such as UiO-66 and HfMOF nanoparticles, which can be potentially used in biochemistry.
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http://dx.doi.org/10.1039/c8sc02210kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179088PMC
October 2018

A G-triplex based molecular beacon for label-free fluorescence "turn-on" detection of bleomycin.

Analyst 2018 Nov;143(22):5474-5480

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu Shandong 273165, P. R. China.

Since bleomycins (BLMs) play a prominent role in the clinical treatment of various cancers, the development of convenient and sensitive detection assays for BLM is of great significance in cancer therapy and related biological mechanism research. Here, taking advantage of the easily controllable and excitation of the G-triplex DNA structure, we reported a facile, label-free G-triplex based functional molecular beacon (G3MB) sensing system for fluorescence "turn-on" detection of BLM based on BLM-Fe(ii) mediated DNA strand scission. In the presence of BLM, the stable hairpin structure of G3MB undergoes an irreversible cleavage in the loop region that contains a 5'-GT-3' recognition site for BLM. The released G-tract DNA fragment self-assembles into a G-triplex-ThT complex showing a strong fluorescence. Owing to the effective locking of G-tracts in the stem of the G3MB and the specific DNA strand scission by BLM which is like a key for the release of G-tracts, the assay shows high sensitivity and selectivity with a detection limit of 0.2 nM. In addition, satisfactory results were obtained for the detection of BLM in human serum samples. Critically, the convenient "mix-and-detect" protocol, fast response and no need for modifying DNA offered a potential application of the proposed strategy for BLM assay in biomedical and clinical studies.
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http://dx.doi.org/10.1039/c8an01208cDOI Listing
November 2018

A stable mesoporous metal-organic framework as highly efficient sorbent of dispersive micro solid-phase extraction for the determination of polycyclic aromatic hydrocarbons by HPLC.

J Sep Sci 2018 Dec 12;41(23):4331-4339. Epub 2018 Nov 12.

Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu, P. R. China.

Owing to the large molecular sizes of polycyclic aromatic hydrocarbons, their adsorption using microporous sorbents leads to a low adsorption capacity. Here, to increase the extraction capacity and detection sensitivity of polycyclic aromatic hydrocarbons, a highly efficient dispersive micro solid-phase extraction method was developed based on a stable mesoporous metal-organic framework named Jilin University China 48. Jilin University China 48 is a super hybrid with large one-dimensional hexagonal nanotube-like channels of 24.5 × 27.9 Å, which exhibits high potential to be an efficient sorbent of dispersive micro solid-phase extraction to adsorb polycyclic aromatic hydrocarbons. By combining with high-performance liquid chromatography, a sensitive method was developed for the determination of seven polycyclic aromatic hydrocarbons. The synthesized Jilin University China 48 exhibited excellent characteristics of stability, good morphology, large surface area, and open adsorption sites. Under the optimized extraction conditions, better extraction results were obtained than that of other methods reported previously. The proposed method exhibited high sensitivity with the limit of detections in the range of 0.021-0.13 ng/mL, good linearity in the range of 0.068-50 ng/mL with related coefficients of >0.9988, satisfactory precision with relative standard deviation of <4.3%, and adequate recoveries between 85.8 to 109.55% for all the target compounds.
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http://dx.doi.org/10.1002/jssc.201800775DOI Listing
December 2018

Simultaneous Detection of Adenosine Triphosphate and Glucose Based on the Cu-Fenton Reaction.

Sensors (Basel) 2018 Jul 4;18(7). Epub 2018 Jul 4.

The Key Laboratory of Life-Organic Analysis, Qufu Normal University, Qufu 273165, China.

Both adenosine triphosphate (ATP) and glucose are important to human health, and their abnormal levels are closely related to angiocardiopathy and hypoglycaemia. Therefore, the simultaneous determination of ATP and glucose with a single test mode is highly desirable for disease diagnostics and early recognition. Herein, a new fluorescence on/off switch sensing platform is developed by carbon nanodots (CNDs) to detect ATP and glucose simultaneously. The fluorescence of CNDs can be quenched by Cu and hydrogen peroxide (H₂O₂), due to the formation of hydroxyl radicals (·OH) produced in the Cu-Fenton reaction. Based on the high affinity of Cu with ATP, the fluorescence of CNDs will recover effectively after adding ATP. Additionally, glucose can be efficiently catalyzed by glucose oxidase (GOx) to generate H₂O₂, so the platform can also be utilized to analyze glucose. Under optimum conditions, this sensing platform displays excellent sensitivity and the linear ranges are from 0.1 to 7 μM for ATP with a limit of detection (LOD) of 30.2 nM, and from 0.1 to 7 mM for glucose with a LOD 39.8 μM, respectively. Benefiting from the high sensitivity and selectivity, this sensing platform is successfully applied for simultaneous detection of ATP and glucose in human serum samples with satisfactory recoveries.
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http://dx.doi.org/10.3390/s18072151DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6069456PMC
July 2018

Highly efficient electrochemical ammonia synthesis via nitrogen reduction reactions on a VN nanowire array under ambient conditions.

Chem Commun (Camb) 2018 May;54(42):5323-5325

College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.

The development of a sustainable route to ammonia production is one of the most attractive targets in chemistry. The primary method of ammonia production, Haber-Bosch process, can bring about excessive consumption of fossil fuels and large CO2 emission. In this communication, we develop a VN nanowire array on carbon cloth (VN/CC) as a high-performance catalyst for the nitrogen reduction reaction (NRR) under ambient conditions. Such an electrocatalyst achieves high ammonia yield (2.48 × 10-10 mol-1 s-1 cm-2) and faradaic efficiency (3.58%) at -0.3 V versus RHE in 0.1 M HCl, outperforming most reported results for N2 fixation under ambient conditions, and even comparing favorably with those obtained under high temperatures and/or pressures. This work not only provides us an attractive catalyst material for the NRR in acidic media, but would also open up an exciting new avenue to the rational design and fabrication of transition metal nitrides for the NRR.
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http://dx.doi.org/10.1039/c8cc00459eDOI Listing
May 2018