Publications by authors named "Faqiong Zhao"

63 Publications

Antifouling ionic liquid doped molecularly imprinted polymer-based ratiometric electrochemical sensor for highly stable and selective detection of zearalenone.

Anal Chim Acta 2022 Jun 30;1210:339884. Epub 2022 Apr 30.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

Zearalenone (ZEN) is a nonsteroidal estrogenic mycotoxin, and its accurate detection in complex biological samples is still a challenge. Herein, an antifouling ratiometric electrochemical sensor has been developed for its detection. In this system, black phosphorus-graphene oxide is used as substrate to amplify the signal; ionic liquid doped molecularly imprinted polymer (MIP) endows the sensing surface not only high recognition ability but also high capability to resist nonspecific adsorption. During MIP preparation a magnetic field is introduced to regulate polymer structure for improving the recognition efficiency of the sensor. The signals of ZEN and poly methylene blue (MB) serve as response signal and internal reference signal, respectively. The peak current of ZEN increases with the increase of ZEN concentration, while the peak current of poly(MB) decreases simultaneously; their ratio changes with ZEN concentration variation. The obtained ratiometric sensor shows a wide linear response range of 0.05-13 μM and a low limit of detection of 12.7 nM (S/N = 3). Furthermore, it has high selectivity, stability and reproducibility, thanks to the advanced antifouling MIP and the built-in correction of poly(MB). The sensor has been successfully applied to determine ZEN in human serum.
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http://dx.doi.org/10.1016/j.aca.2022.339884DOI Listing
June 2022

Organic-Inorganic Hybrid Flower-Shaped Microspheres Applied in Photoelectrochemical Sensing.

ACS Appl Mater Interfaces 2022 May 10. Epub 2022 May 10.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei Province 430072, PR China.

Organic-inorganic hybrid materials are rarely applied in photoelectrochemical (PEC) sensing because of the serious charge-carrier recombination in organic conjugated polymers. In this work, a series of poly(3,4-ethylenedioxythiophene) (PEDOT)/ZnInS hybrid flower-shaped microspheres were synthesized using ionic liquids (ILs) as the supporting electrolyte for EDOT electropolymerization and as the regulating reagent for controlling ZnInS growth, respectively. It was found that the hybrid material [HOEMIM]NTf-PEDOT/[HOEMIM]BF-ZnInS ([HOEMIM]: 1-hydroxyethyl-3-methylimidazolium cation; NTf: bis(trifluoromethanesulfonyl)amide) was the optimal one, with a smooth, transparent, and continuous polymer film covering the uniform and ordered cross-linked nanosheet arrays. The hybrid material could produce a high anodic photocurrent, which was about 78 times as high as that produced by the [HOEMIM]BF-ZnInS. The enhancement effect should be the highest among all the organic-inorganic hybrid materials reported so far. This was related to its unique micromorphology structure, p-n heterojunction, and the coexisting ILs, which restrained the charge-carrier recombination in PEDOT and enhanced PEDOT sensitization to ZnInS. Then, a carcinoembryonic antigen PEC immunosensor was constructed based on the photoanodic sensing platform, and it exhibited good performance. Furthermore, the [HOEMIM]BF-ZnInS was treated with NaClO solution to create the [HOEMIM]NTf-PEDOT/[HOEMIM]BF-S-ZnInSO general platform for both photoanodic and photocathodic sensing. As a proof of concept, L-cysteine and dissolved oxygen were used as models for photoanodic and photocathodic sensing, respectively. The results demonstrated that the general PEC platform was quite competent. This work opens up a window for the design of organic-inorganic hybrid PEC materials and will promote the application of such hybrid materials in PEC biosensing.
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http://dx.doi.org/10.1021/acsami.2c02332DOI Listing
May 2022

Kill two birds with one stone: Selective and fast removal and sensitive determination of oxytetracycline using surface molecularly imprinted polymer based on ionic liquid and ATRP polymerization.

J Hazard Mater 2022 07 14;434:128907. Epub 2022 Apr 14.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

Oxytetracycline (OTC) residue in food and environment has potential threats to ecosystem and human health, thus its sensitive monitoring and effective elimination are very important. In this work, a new molecularly imprinted polymer (MIP) composite was prepared through atom transfer radical polymerization by using OTC as template, gold nanoparticles modified carbon nanospheres (Au-CNS) as supporter, ionic liquids (IL) as functional monomer and cross-linking agent. The obtained [email protected] composite was characterized by Fourier transform infrared absorption spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. It displayed high imprinting factor (5.50) and adsorption capacity (56.7 mg g), and could achieved the adsorption equilibrium in short time (about 15 min). Results also illustrated that the adsorption process basically conformed to the quasi-second-order kinetic model and Freundlich model, and [email protected] could be recycled at least 5 times. Furthermore, a sensitive OTC electrochemical sensor was developed by combining [email protected] with IL-modified carbon nanocomposites ([email protected]). The resulting sensor demonstrated a linear response to OTC in the wide range of 0.02-20 μM, and the detection limit was down to 5 nM. It also had the advantages of high selectivity, fast elution/regeneration and simple construction procedure. The sensor had been applied to the detection of real samples, and acceptable recovery (96.4%-106%) and RSD (3.2%-6.2%) were obtained. This work expands the application of IL-based MIP in pollutant monitoring and enriching.
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http://dx.doi.org/10.1016/j.jhazmat.2022.128907DOI Listing
July 2022

Molecularly imprinted ratiometric electrochemical sensor based on carbon nanotubes/cuprous oxide nanoparticles/titanium carbide MXene composite for diethylstilbestrol detection.

Mikrochim Acta 2022 03 9;189(4):137. Epub 2022 Mar 9.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, People's Republic of China.

Conventional molecularly imprinted polymers (MIP)-based electrochemical sensors are generally susceptible to the changes of personal operation, electrode surface, and solution conditions. Herein, a ratiometric strategy was employed through introducing CuO nanoparticles (NPs) as inner reference probe to realize the reliable detection of diethylstilbestrol (DES). MIP film was prepared by electropolymerization of 1H-pyrrole-3-carboxylicacid in the presence of DES on carbon nanotubes/cuprous oxide/titanium carbide (CNT/CuO NPs/TiCT) modified electrodes. The TiCT with accordion-like structure not only possessed good electrical conductivity, but also facilitated the immobilization of CuO NPs, which contributed to stabilizing the signal. CNT was introduced to further improve the sensitivity of the sensor. Under optimum conditions, the MIP/CNT/CuO NPs/TiCT electrochemical sensors showed a broad linear response range of 0.01 to 70 μM, and a low detection limit of 6 nM (S/N = 3). Moreover, the sensor was applied to detect DES in real samples including lake water, milk, and pork, and the recoveries for spiked standard were 88-112%. Thus, this work provides a new way for reliable DES detection.
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http://dx.doi.org/10.1007/s00604-022-05249-xDOI Listing
March 2022

Water based-deep eutectic solvent for ultrasound-assisted liquid-liquid microextraction of parabens in edible oil.

Food Chem 2022 Jul 26;383:132586. Epub 2022 Feb 26.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

A novel water-based deep eutectic solvent was synthesized and used for the ultrasound-assisted liquid-liquid microextraction of parabens in edible oil and for their determination by high performance liquid chromatography. Herein, the water-based deep eutectic solvent was formulated at room temperature by tetrabutylammonium chloride as hydrogen bond acceptor and water as hydrogen bond donor at the molar ratio of 1:5. As component, water has the effect on tailoring the physicochemical properties of water-based deep eutectic solvent and assisting tetrabutylammonium chloride (hydrogen bond acceptor) capturing parabens (hydrogen bond donor) through in-situ deep eutectic solvent formation. The developed method has satisfactory linearity (1.5-500 μg/L), limits of detections (0.2-0.4 μg/L), precisions (RSDs ≤ 5.8%), and was fruitfully applied to detect parabens in edible oil with excellent recoveries (85.1-106.8%). The feature of the procedure lies in simplicity, low cost and high sensitivity, and this can be extended for the efficient separation of other hydrophobic compounds.
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http://dx.doi.org/10.1016/j.foodchem.2022.132586DOI Listing
July 2022

Fabrication of surface molecularly imprinted electrochemical sensor for the sensitive quantification of chlortetracycline with ionic liquid and MWCNT improving performance.

Talanta 2022 Mar 9;239:123130. Epub 2021 Dec 9.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

Chlortetracycline (CTC) is a widely used broad-spectrum antibiotic, its residue likely occurs in the environment and foods, bringing some negative effects to human health. Hence the detection and quantification of CTC in environmental and food samples is relevant. Herein, a novel electrochemical sensor based on surface molecularly imprinted polymer (SMIP) was constructed for the quantitative detection of CTC. The SMIP was synthesized by using ionic liquid (IL) functionalized MWCNT (MWCNT-IL) as supporter, 1-carboxymethyl-3-vinylimidazolium bromide (IL) as functional monomer, CTC as template, ethylene glycol dimethyl acrylate as crosslinker, and azobisisobutyronitrile as initiator. The obtained composite IL-SMIP exhibited high adsorption capacity for CTC and the imprinting factor was ca. 4.1. It was found that IL played an important role in improving the property of SMIP, which was also evaluated by DFT-based calculation. The resulting sensor IL-SMIP/MWCNT-IL/GCE showed high selectivity, sensitivity and reproducibility. CTC could be quantified from 0.4 μM to 55 μM with a detection limit of 0.08 μM (S/N = 3) under the optimized conditions. The practical applicability of the sensor was demonstrated successfully by determining CTC in real samples.
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http://dx.doi.org/10.1016/j.talanta.2021.123130DOI Listing
March 2022

A novel ratiometric electrochemical sensor based on dual-monomer molecularly imprinted polymer and Pt/CoO for sensitive detection of chlorpromazine hydrochloride.

Anal Chim Acta 2022 Jan 3;1190:339245. Epub 2021 Nov 3.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China.

In this work, a novel signal on/off ratiometric electrochemical sensor for the selective detection of chlorpromazine (CPZ) was developed. The sensor was constructed by electrodepositing dual-monomer molecularly imprinted polymer (DMMIP) film on the surface of Pt/CoO nanoparticles modified glassy carbon electrode, using CPZ as template molecule, methylene blue and catechol as functional monomers. The copolymerization of two monomers increased the diversity of functional groups for binding template molecules, and enhanced stability. The quantitative detection of CPZ was performed by differential pulse voltammetry, using the peak current of poly (methylene blue) as reference signal and the peak current of CPZ as indicating signal. The results showed that the developed DMMIP sensor not only possessed high selectivity and sensitivity, but also exhibited satisfactory anti-interference ability. Under the optimum conditions, a linear detection range of 0.005-9 μmol L (R = 0.9962) was obtained, and the limit of detection was 2.6 nmol L. Moreover, the sensor showed good reproducibility and stability toward CPZ detection. It was applied to detect CPZ in serum and pharmaceutical samples, and satisfactory recoveries (ranging from 95.3% to 108.0%) were achieved.
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http://dx.doi.org/10.1016/j.aca.2021.339245DOI Listing
January 2022

A novel ratiometric electrochemical sensor for the selective detection of citrinin based on molecularly imprinted poly(thionine) on ionic liquid decorated boron and nitrogen co-doped hierarchical porous carbon.

Food Chem 2021 Nov 16;363:130385. Epub 2021 Jun 16.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

Citrinin can cause serious human diseases, thus its detection in foods is necessary. Herein, a molecularly imprinted polymer-based ratiometric electrochemical sensor (MIP-RECS) was presented for citrinin detection. The sensor was fabricated by electropolymerization, using thionine as monomer and citrinin as template. The ionic liquid decorated boron and nitrogen co-doped hierarchical porous carbon (BN-HPC) as supporter, provided large surface for anchoring thionine and citrinin. Poly(thionine) not only acted as MIP, but also acted as reference probe. When [Fe(CN)] was adopted as indicating probe, the resulting sensor demonstrated a wide linear detection range (i.e. 1 × 10-10 ng mL) and a low detection limit (i.e. 1 × 10 ng mL).The sensor was applied to the detection of spiked citrinin in real samples, and satisfactory recovery (i.e. 97% - 110%) was obtained. Hence, it was promising for citrinin detection.
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http://dx.doi.org/10.1016/j.foodchem.2021.130385DOI Listing
November 2021

Determination of patulin using dual-dummy templates imprinted electrochemical sensor with PtPd decorated N-doped porous carbon for amplification.

Mikrochim Acta 2021 04 2;188(5):148. Epub 2021 Apr 2.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, People's Republic of China.

A novel dual-dummy templates imprinted electrochemical sensor has been fabricated for the detection of patulin. Herein, 2-oxindole (2-oxin) and 6-hydroxynicotinic acid (6-HNA) as the dummy templates, 4-aminothiophenol as functional monomer, and ionic liquid (IL) as electropolymerization electrolyte are employed to prepare molecularly imprinted polymer (MIP) film. 2-Oxin and 6-HNA have multiple groups and the obtained MIP possesses different types of imprinted sites, thereby achieving a better recognition capacity than that of single-dummy imprinted film. ILs can regulate the density of molecularly imprinted film and facilitate effective molecular recognition. The composite of PtPd decorated N-doped porous carbon has good conductivity and large surface area, and can amplify the signal. With the aid of electrochemical probe [Fe(CN)] (0.16 V vs. SCE) patulin can be detected. Under the optimal conditions, this sensor shows a detection range from 0.01 to 10 μg L, with a detection limit of 7.5 × 10 μg L (S/N = 3). Two spiked juice samples were analyzed by this method, and the recovery ranges from 94 to 99.8% with RSD values of 2.4-4.6% (n = 3), indicating that this method can be applied for the detection of patulin in real samples. A novel dual-dummy templates imprinted electrochemical sensor is firstly fabricated for the detection of patulin. This sensor exhibits high recognition capacity and sensitivity.
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http://dx.doi.org/10.1007/s00604-021-04812-2DOI Listing
April 2021

Preparation of functionalized graphene and ionic liquid co-doped polypyrrole solid phase microextraction coating for the detection of benzoates preservatives.

Talanta 2021 Jun 2;228:122231. Epub 2021 Mar 2.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China. Electronic address:

A novel solid-phase microextraction coating based on polypyrrole (Ppy) with manganese dioxide modified 6-aminohexanoic acid functionalized graphene (MnO-fGr) and 1-allyl-3-vinylimidazolium bis(trifluoromethylsulfonyl)imide ([AVIm]NTf) as dopants (Ppy/MnO-fGr/[AVIm]NTf) was successfully prepared by electrochemical method. The composite coating was characterized by scanning electron microscope (SEM), Fourier infrared spectrum (FT-IR) and thermogravimetry (TG). The composite coating showed coarse structure, which could improve the specific surface area of it, and according to the TG curve, it also had good thermal stability. The composite coating was used for the headspace-solid phase microextraction (HS-SPME) and chromatographic analysis of benzoates (i.e. methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate),by coupling with gas chromatography with hydrogen flame ionization detector (GC-FID). Under optimal conditions, their enrichment factors were 140-460, linear detection ranges were 25-60000 ng L, and detection limits were 2.84-6.42 ng L. The standard deviations for five consecutive extractions of 100 μg L analytes were 3.00-10.20%, while the standard deviation for the extractions of 100 μg L analytes with five different coatings were 5.70-13.80%. The proposed method was applied for the detection of the benzoates in cosmetics, and the recoveries for the spiked benzoates were 82.8-116.8%.
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http://dx.doi.org/10.1016/j.talanta.2021.122231DOI Listing
June 2021

Ionic liquid functionalized 3D graphene-carbon nanotubes‒AuPd nanoparticles‒molecularly imprinted copolymer based paracetamol electrochemical sensor: Preparation, characterization and application.

Talanta 2021 Mar 2;224:121845. Epub 2020 Nov 2.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

An innovative electrochemical sensor for paracetamol (PCM) determination was fabricated by electropolymerization imprinting on three-dimension (3D) AuPd nanoparticles‒ionic liquid (IL) functionalized graphene‒carbon nanotubes nanocomposite (AuPd/GN-CNTs-IL) modified glassy carbon electrode. The GN-CNTs supported AuPd alloy nanoparticles were prepared via one-pot hydrothermal method in the presence of IL (i.e. 1-hydroxyethyl-3-methyl imidazolium bis[(trifluoromethyl) sulfonyl] imide), which not only promoted the formation of small AuPd alloy nanoparticles, but also acted as "spacer" to prevent the π-π stacking and aggregation of graphene sheets and carbon nanotubes. The resulting composite had large surface area and high electrocatalysis. The PCM imprinted poly(carbazole-co-pyrrole) exhibited good recognition to PCM and had high stability. Based on the synergic effect of PCM imprinted copolymer and 3D AuPd/GN-CNTs-IL nanocomposite, a highly selective and sensitive electrochemical sensor was established. It presented a good linear relationship from 0.10 to 10 μM with a low limit of detection of 50 nM (S/N = 3). The sensor could be applied to the detection of PCM in biological samples, with acceptable recoveries (84.5%-102%). In addition, it was successfully used to monitor the concentration of PCM in urine from a patient with fever cold.
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http://dx.doi.org/10.1016/j.talanta.2020.121845DOI Listing
March 2021

Determination of fluoroquinolones in foods using ionic liquid modified FeO/MWCNTs as the adsorbent for magnetic solid phase extraction coupled with HPLC.

Anal Methods 2020 09 28;12(36):4457-4465. Epub 2020 Aug 28.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China.

In this work, a simple and sensitive method based on FeO/multi-walled carbon nanotubes/ionic liquid (FeO/MWCNTs/IL) as the adsorbent for magnetic solid phase extraction coupled with high performance liquid chromatography was developed for the determination of trace fluoroquinolones in foods. After a simple one-pot solvothermal synthesis, FeO/MWCNTs were further modified with an amine-terminated ionic liquid to enhance their dispersibility and extraction capacity. The morphology, structure and magnetic properties of the composite adsorbent were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectrometry and vibrating-sample magnetometry. Under the optimized extraction and detection conditions, the studied fluoroquinolones were enriched effectively and separated well and their UV signals were linear to their concentrations in the range of 4-1000 ng mL, with correlation coefficients ranging from 0.9958 to 0.9990. The enrichment factors were 29.1-43.9 fold and the limits of detection were 0.33-0.78 ng mL. The spiked recoveries were 85.4-105.9% for milk and 85.2-103.7% for pork samples, with relative standard deviations of 0.8-5.7%. The developed method provided a fast, sensitive and reliable determination platform for fluoroquinolones in complex real samples.
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http://dx.doi.org/10.1039/d0ay01045fDOI Listing
September 2020

Novel BiWO p-n Homojunction Nanostructure: Preparation, Characterization, and Application for a Self-Powered Cathodic Photoelectrochemical Immunosensor.

ACS Sens 2020 09 31;5(9):2876-2884. Epub 2020 Aug 31.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, P. R. China.

Synthesizing novel cathodic photoactive materials with high photoelectrochemical (PEC) performance is urgently important for the development of photocathodic sensors. Herein, a novel photocathode material, Bi self-doped BiWO ( BiWO) p-n homojunction, is prepared a simple ethylene glycol-assisted solvothermal reduction for the first time. Compared with pristine BiWO, BiWO possesses a narrower band gap and higher light harvesting ability. Among the synthesized materials, BiWO exhibits the highest photocurrent response, which is 23 times that of pure BiWO because of the synergistic effect of doped Bi and the p-n homojunction. The open circuit potential, "V-shaped" Mott-Schottky plot, linear sweep voltammetry curve, and transient photocurrent demonstrate the p-n homojunction characteristics of the material well. By using the BiWO p-n homojunction as the photocathode for sensing and the plasmonic WO/Au composite as the photoanode for signal amplification, a new self-powered membraneless PEC immunosensor is established for a highly sensitive detection of human epididymal protein 4. This study offers a new idea for designing novel photocatalysts with satisfactory performance, and the BiWO p-n homojunction is expected to act as a promising PEC platform for developing various self-powered biosensors.
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http://dx.doi.org/10.1021/acssensors.0c01044DOI Listing
September 2020

Ionic liquid assisted molecular self-assemble and molecular imprinting on gold nanoparticles decorated boron-doped ordered mesoporous carbon for the detection of zearalenone.

Talanta 2020 Sep 14;217:121032. Epub 2020 Apr 14.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 30072, Hubei Province, PR China. Electronic address:

Accurate and early diagnosis of zearalenone (ZEN) is particularly significant to the food safety. Herein, we propose an ionic liquid assisted self-assembly molecular imprinting strategy for ZEN based on ionic liquid functionalized boron-doped ordered mesoporous carbon -gold nanoparticles composite (BOMC-IL-Au NPs). During the composite synthesis, increased well-dispersed and uniform Au NPs are deposited on the surface of IL modified BOMC, due to the strong electrostatic interaction between AuCl and positively charged IL. For molecular imprinting, the BOMC-IL-Au NPs/GCE is immersed into p-aminothiophenol (p-ATP) solution and template solution in turn. Thus, the mercapto group contained p-ATP self-assembles on the Au NPs. Subsequently, the template molecules self-assemble onto the composite to form dense template layer, because of the hydrophobic interaction, π-π and hydrogen bond between template and IL/or p-ATP. After electropolymerization, the template layer is embedded into the p-ATP polymer membrane and produces lots of imprinting sites. Hence, the obtained sensor exhibits high sensitivity and selectivity. Under the optimal conditions, zearalenone can be quantified from 5 × 10 to 1 ng mL with the low detection limit of 1 × 10 ng mL, by using [Fe(CN)] probe and square wave voltammetry. This strategy can also be employed to construct sensors for the detection of other substances.
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http://dx.doi.org/10.1016/j.talanta.2020.121032DOI Listing
September 2020

Space-confined synthesis of ordered mesoporous carbon doped with single-layer MoS-boron for the voltammetric determination of theophylline.

Mikrochim Acta 2019 10 13;186(11):694. Epub 2019 Oct 13.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, People's Republic of China.

A space-confined synthesis method is employed for the preparation of a single-layer MoS-boron doped ordered mesoporous carbon nanocomposite. A phenol-formaldehyde resin is used as carbon source to create a confined space for the formation of single-layer MoS. The addition of pluronic F127, as a soft template, suppresses the stacking of MoS layers and makes the composite porous. The nanocomposite is characterized by scanning electron and transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The single-layer MoS sheets have a lateral size of about 5 nm and are uniformly embedded in the composite. They possess numerous active edge sites and display a strong synergistic effect with other components. The composite is modified on a glassy carbon electrode, followed by the electrochemical imprinting of theophylline, and the resulting electrode exhibits good electrochemical response to theophylline. The linear response range is 0.01-250 μM by differential pulse voltammetry, and the lower detection limit is 5 nM. It has been successfully applied to the determination of theophylline in spiked tea drink samples. Graphical abstract Single-layer MoS-boron doped ordered mesoporous carbon nanocomposite has large surface area and high catalysis, when coupling with molecularly imprinted polymer the resulting electrode shows highly sensitive and selective response to theophylline.
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http://dx.doi.org/10.1007/s00604-019-3824-8DOI Listing
October 2019

A molecularly imprinted copolymer based electrochemical sensor for the highly sensitive detection of L-Tryptophan.

Talanta 2020 Jan 8;206:120245. Epub 2019 Aug 8.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

A novel L-tryptophan (L-Trp) electrochemical sensor is fabricated, which is based on the molecularly imprinted copolymer (MIP) of dual -functional monomers and ionic liquid (i.e. 1-butyl-3-methylimidazolium hexafluorophosphate) functionalized multi-walled carbon nanotubes ([email protected]). The [email protected] is prepared via ion exchange, while the MIP is synthesized by using L-Trp as template, styrene and 4-vinylbenzoic acid as functional monomers, Triton X-100 as emulsifier, 1, 2-divinylbenzene as cross-linking reagent and KSO as initiator. Prior to copolymerization the functional monomer 4-vinylbenzoic acid is combined with the template molecule by forming amide bond. The template molecule is eluted by hydrolysis, and rebound by electrostatic, hydrogen-bond and π-π interaction. To construct L-Trp sensor a little of Nafion is introduced to enhance the stability and to promote rebinding. The resulting sensor [email protected]/GCE shows a wide linear range (8 nM-26 μM) and a low detection limit (6 nM). It is successfully applied to the determination of L-Trp in oral liquid and human serum samples.
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http://dx.doi.org/10.1016/j.talanta.2019.120245DOI Listing
January 2020

[email protected]@RuDS nanocomposite based plasmon-enhanced electrochemiluminescence sensor for the highly sensitive detection of glutathione.

Talanta 2019 Nov 10;204:402-408. Epub 2019 Jun 10.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

A novel plasmon enhanced electrochemiluminescence (ECL) sensor was fabricated for the highly sensitive detection of glutathione (GSH). First, Au nanoparticles (AuNPs) were coated with silica dioxide to prevent the direct contact of AuNPs and luminophore Ru(bpy); then Ru(bpy)-containing silica layer (RuDS) was allowed to grow onto the obtained [email protected] Owing to the high luminescence efficiency of RuDS and the surface plasmon resonance of AuNPs, the nanocomposite [email protected]@RuDS exhibited large ECL signal. As free radical scavenger, GSH could react with tri-n-propylamine radical (i.e. TPA) and effectively suppress the excitation of Ru(bpy), thus made the ECL signal significantly decrease. By using Nafion as immobilization reagent, the resulting [email protected]@RuDS/GCE sensor showed wide linear response ranges (1.0 fM-1.0 nM and 1.0 nM-1.0 μM) and low detection limit (0.5 fM, S/N=3) for GSH. In addition, it had excellent stability, repeatability and reproducibility. The sensor was applied to the detection of GSH in human serum samples and satisfactory results were achieved.
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http://dx.doi.org/10.1016/j.talanta.2019.06.030DOI Listing
November 2019

Z-scheme I-BiOCl/CdS with abundant oxygen vacancies as highly effective cathodic material for photocathodic immunoassay.

Biosens Bioelectron 2019 Sep 19;141:111443. Epub 2019 Jun 19.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China. Electronic address:

A novel label-free photocathodic immunosensor was constructed by introducing a direct Z-scheme I-BiOCl/CdS cathodic material as highly effective photocatalyst for the selective detection of carcino embryonic antigen (CEA). The Z-scheme photocatalyst could promote the separation of photogenerated carriers and showed a more negative conduction band potential. In addition, the I-BiOCl with abundant oxygen vacancies could activate electron acceptors (i.e. O and HO) and made them reduce more completely, thus the sensitivity of the photocathodic immunosensor was significantly improved. Afterward, CEA antibody (Ab) was employed for the selective recognition of CEA target, which was covalently bonded to the substrate material. The formation of immune complexes hindered the diffusion of electron acceptors, thus the photocurrent decreased. Under the optimized conditions, the photocathodic immunosensor displayed abroad linear range (0.01-40.0 ng/mL) and a low detection limit (0.002 ng/mL) for CEA detection. Furthermore, acceptable reproducibility, excellent selectivity and high anti-interference ability were achieved. This work provides a new horizon for the design and development of Z-scheme cathodic materials as photoactive material for photocathodic biosensing.
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http://dx.doi.org/10.1016/j.bios.2019.111443DOI Listing
September 2019

Fe O /reduced graphene oxide-carbon nanotubes composite for the magnetic solid-phase extraction and HPLC determination of sulfonamides in milk.

J Sep Sci 2019 Mar 13;42(5):1058-1066. Epub 2019 Feb 13.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Hubei Province, Wuhan, P. R. China.

A novel magnetic adsorbent Fe O /reduced graphene oxide-carbon nanotubes, was prepared by one-pot solvothermal synthesis method. It was characterized by scanning electron microscopy, X-ray powder diffraction and vibrating sample magnetometry. The diameter of Fe O microparticles was about 350 nm, which were covered by carbon nanotubes and reduced graphene oxide sheets, while carbon nanotubes inserted between the reduced graphene oxide sheets effectively prevented their aggregation. The composite had large surface area and good magnetic property, suiting for magnetic solid-phase extraction and the determination of sulfonamides, by coupling with high-performance liquid chromatography. Under the optimized conditions (including extraction time, amount of adsorbent, solution pH, ionic strength and desorption conditions), a good linear was achieved in the concentration range of 5-500 μg/L and the low limits of detection and low limits of quantification were 0.35-1.32 and 1.16-4.40 μg/L, respectively. The enrichment factors were estimated to be 24.72 to 30.15 fold. The proposed method was applied for the detection of sulfonamides in milk sample and the recoveries were 88.4-105.9%, with relative standard deviations of 0.74-5.38%.
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http://dx.doi.org/10.1002/jssc.201801177DOI Listing
March 2019

One-Pot Synthesis of N-Graphene Quantum Dot-Functionalized I-BiOCl Z-Scheme Cathodic Materials for "Signal-Off" Photoelectrochemical Sensing of Chlorpyrifos.

ACS Appl Mater Interfaces 2018 Oct 4;10(41):35281-35288. Epub 2018 Oct 4.

Key Laboratory of Analytical Chemistry for Biology and Medicine, College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , P. R. China.

A Z-scheme I-BiOCl/N-GQD (i.e., nitrogen-doped graphene quantum dot) heterojunction was prepared by a one-pot precipitation method at room temperature. The doped iodine decreased the band gap of BiOCl, the introduced N-GQDs enhanced light harvesting and prolonged the photogenerated electron lifetime, and the resultant Z-scheme heterojunction promoted the spatial separation of interfacial charges. Thus, the composite showed high photoelectrochemical activity and a big cathodic photocurrent signal. On the basis of the coordination of chlorpyrifos with surface Bi(III) of the composite, a cathodic photoelectrochemical sensor was constructed for the selective detection of chlorpyrifos. In this case, chlorpyrifos decreased the lifetime of photogenerated electrons, so the photocurrent became small. Furthermore, the photocurrent changed and the logarithm of chlorpyrifos concentration presented a linear relationship. The linear range was 0.3-80 ng mL, and the limit of detection was estimated to be 0.01 ng mL (defined as S/N = 3). The present strategy can also be used for the design and fabrication of other PEC sensors suitable for different analytes.
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http://dx.doi.org/10.1021/acsami.8b12979DOI Listing
October 2018

Tremella-like ZnInS/graphene composite based photoelectrochemical sensor for sensitive detection of dopamine.

Talanta 2018 Aug 22;186:459-466. Epub 2018 Apr 22.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

Tremella-like ZnInS (ZISt) and flower-like microsphere ZnInS (ZISm) were synthesized via a straightforward hydrothermal method. It was found that the ZISt was superior to ZISm for photoelectrochemical (PEC) sensing because of its large surface area and high photocatalytic activity. A composite of ZISt and graphene (GR) was prepared and used for the PEC sensing of dopamine (DA). Here DA acted as an electron donor to scavenge the hole and inhibit the charge recombination. The GR enhanced visible light absorption and accelerated electron transfer, amplifying the photocurrent signal. The strong chelating coordination interaction between DA and Zn(II) in ZISt guaranteed the selective adsorption of target analyte. Thus the resulting ZISt/GR photoelectrode showed sensitive and selective PEC response to DA. Under the optimized conditions, the linear response range was from 0.01 to 20 μM, and the detection limit was down to 0.001 μM. Additionally, the sensor had good stability and reproducibility, and it could be used for the detection of DA in real samples.
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http://dx.doi.org/10.1016/j.talanta.2018.04.063DOI Listing
August 2018

Graphene-doped electrochemical copolymer coating of 2,2-bithiophene and 3-methylthiophene for the highly effective solid-phase microextraction of volatile benzene homologues.

J Sep Sci 2018 May 12;41(10):2197-2206. Epub 2018 Mar 12.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Science, Wuhan University, Wuhan, P. R. China.

We report the electrochemical fabrication of a poly(2,2-bithiophene-co-3-methylthiophene)-graphene composite coating and its application in the headspace solid-phase microextraction and gas chromatography determination of benzenes (i.e., bromobenzene, 4-bromotoluene, 2-nitrotoluene, 3-nitrotoluene and 1,2,4-trichlorobenzene). The coating was uniform and showed cauliflower-like microstructure. It had high thermal stability (up to 375°C) and could be used for at least 180 times of solid-phase microextraction without a decrease in extraction performance. Furthermore, it presented high extraction capacity for the benzenes due to the hydrophobic effect and π-π interaction between the analytes and the coating. Under optimized extraction conditions, good linearity (correlation coefficients higher than 0.9946), wide linear range (0.01-50 μg/L), and low limits of detection (5.25-12.5 ng/L) were achieved for these analytes. The relative standard deviation was lower than 5.7% for five successive measurements with one fiber, and the relative standard deviation for fiber-to-fiber was 4.9-6.8% (n = 5). The solid-phase microextraction and gas chromatography method was successfully applied for the determination of three real samples, and the recoveries for standards added were 89.6-106% for nail polish, 85.8-110% for hair dye, and 90-106.2% for correction fluid, respectively.
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http://dx.doi.org/10.1002/jssc.201701330DOI Listing
May 2018

Fabrication of bi-monomer copolymer of pyrrole-indole for highly efficient solid phase microextraction of benzene derivatives.

Talanta 2018 Jan 10;176:450-455. Epub 2017 Aug 10.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

A procedure for direct electrochemical deposition of poly(pyrrole-indole) on gold nanoparticles coated stainless steel wire was established, and the formation of copolymer was confirmed by infrared spectroscopy. The synthesized coating showed unique microstructure, excellent extraction efficiency (2-10 times of corresponding single-component coating), high thermal stability (up to 280°C) and good durability (could be used for more than 200 times). As a novel and promising extraction coating, it was used for the headspace solid phase microextraction-gas chromatography detection of some benzene derivatives, including chlorobenzene, bromobenzene, p-bromotoluene, m-nitrotoluene and p-nitrotoluene. Under the optimized conditions, their GC peak areas were linear to their concentrations in the ranges of about 0.05-100μgL, and the detection limits were 0.012-0.029μgL (S/N = 3). The run-to-run RSDs were lower than 3.9% (n = 4), the fiber-to-fiber RSDs were 4.3-7.8% (n = 4). The proposed method was successfully applied to the determination of benzene derivatives mentioned above in real samples with good recoveries from 88.3% to 103.7%.
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http://dx.doi.org/10.1016/j.talanta.2017.08.035DOI Listing
January 2018

A Poly(ethylenglycol) Functionalized ZIF-8 Membrane Prepared by Coordination-Based Post-Synthetic Strategy for the Enhanced Adsorption of Phenolic Endocrine Disruptors from Water.

Sci Rep 2017 08 21;7(1):8912. Epub 2017 Aug 21.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, P. R. China.

Metal-organic framework (MOF) membranes have received increasing attention as adsorbents, yet single phase MOF membranes have certain limitations, which frustrate their capacity performance. In this work a MOF composite membrane was successfully prepared by a facile and green strategy through reasonable design. At first, a defect-free ZIF-8 membrane was fabricated on an ionic liquid modified pencil bar by a solvothermal method. Then, a novel poly(ethylenglycol) functionalized ZIF-8 composite membrane (ZIF-8/PEG-NH) was prepared through a flexible coordination-based post-synthetic modification strategy. We found that reaction time and temperature were two crucial factors for successfully fabricating well-defined ZIF-8/PEG-NH membrane. Besides, the adsorption of phenolic endocrine disruptors (e.g., 4-nonylphenol) on original ZIF-8 membrane and ZIF-8/PEG-NH membrane was investigated, and the good adsorption selectivity of ZIF-8/PEG-NH membrane towards 4-nonylphenol was demonstrated, with high adsorption capacity and fast adsorption dynamics. Excitingly, such ZIF-8/PEG-NH membrane was successfully employed for the selective detection of 4-nonylphenol from environmental water samples, demonstrating its great application potential in environmental monitoring.
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http://dx.doi.org/10.1038/s41598-017-09364-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5566371PMC
August 2017

Electrochemical preparation of poly(3-methylthiophene-carbazole)/graphene oxide composite coating for the highly effective solid-phase microextraction of some fragrance.

Talanta 2017 Aug 31;171:61-67. Epub 2017 Mar 31.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

A poly(3-methylthiophene-carbazole)/graphene oxide composite coating was prepared on a stainless steel wire through electrochemical method. It showed high extraction efficiency, thermal stability and durability than those of corresponding single-component coatings due to the synergistic effect of different components. The resulting fiber was used for the headspace solid phase microextraction of octanal, nonanal, decanal, undecanol and dodecanol, followed by gas chromatography detection. The results showed that their GC peak areas were linear to their concentrations in the ranges of about 0.05-100μgL, the detection limits were 22.6-40.5ngL (S/N=3). The run-to-run RSD was smaller than 4.5% (n=4), and the fiber-to-fiber RSD was 4.0-9.3% (n=4). The method was successfully applied to the determination of the five analytes in candy, orange fruit and flower.
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http://dx.doi.org/10.1016/j.talanta.2017.03.097DOI Listing
August 2017

High-Quality Metal-Organic Framework ZIF-8 Membrane Supported on Electrodeposited ZnO/2-methylimidazole Nanocomposite: Efficient Adsorbent for the Enrichment of Acidic Drugs.

Sci Rep 2017 01 4;7:39778. Epub 2017 Jan 4.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, P. R. China.

Metal-organic framework (MOF) membranes have received increasing attention as adsorbents, yet the defects in most membrane structures greatly thwart their capacity performance. In this work, we fabricated a novel ZnO/2-methylimidazole nanocomposite with multiple morphology by electrochemical method. The nanocomposite provided sufficient and strong anchorages for the zeolitic imidazolate frameworks-8 (ZIF-8) membrane. Thus, a crack-free and uniform MOF membrane with high performance was successfully obtained. In this case, 2-methylimidazole was believed to react with ZnO to form uniform ZIF nuclei, which induced and guided the growth of ZIF-8 membrane. The as-prepared ZIF-8 membrane had large surface area and good thermal stability. As expected, it displayed high adsorption capacity for acidic drugs (e.g., ibuprofen, ketoprofen and acetylsalicylic acid) as they could interact through hydrophobic, hydrogen bonding and π-π stacking interaction. Accordingly, by coupling with gas chromatography the ZIF-8 membrane was successfully applied to the real-time dynamic monitoring of ibuprofen in patient's urine.
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http://dx.doi.org/10.1038/srep39778DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209695PMC
January 2017

Doping of three-dimensional porous carbon nanotube-graphene-ionic liquid composite into polyaniline for the headspace solid-phase microextraction and gas chromatography determination of alcohols.

Anal Chim Acta 2016 Dec 11;948:48-54. Epub 2016 Nov 11.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, Hubei Province, PR China. Electronic address:

In this work, ionic liquid (IL, i.e. 1-hydroxyethyl-3-methylimidazolium tetrafluoroborate), carboxyl multiwall carbon nanotubes (MWCNTs) and reduced graphene oxide (rGO) were used to prepare three-dimensional porous material (MWCNTs-rGO-IL) by one-step self-assembly, then it was co-electrodeposited with polyaniline (PANI) on stainless steel wires by cyclic voltammetry. The resulting coating (PANI-MWCNTs-rGO-IL) was characterized by using FT-IR and scanning electron microscopy etc, and it showed porous structure and had high thermal stability. Furthermore, it was found to be very suitable for the headspace solid-phase microextraction of alcohols (i.e. octanol, nonanol, geraniol, decanol, undecanol and dodecanol). By coupling with gas chromatography, wide linear ranges and low limits of detection (i.e. 2.2-28.3 ng L) were obtained for the alcohols. The coating also presented good repeatability and reproducibility; the relative standard deviations for intra-fiber and fiber-to-fiber were less than 5.6% (n = 5) and 7.0% (n = 5) respectively. In addition, the proposed method was successfully applied to the determination of alcohols in tea drinks, and the recoveries for standards added were 85.6-114%.
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http://dx.doi.org/10.1016/j.aca.2016.11.020DOI Listing
December 2016

Facile preparation of molecularly imprinted polypyrrole-graphene-multiwalled carbon nanotubes composite film modified electrode for rutin sensing.

Talanta 2016 Dec 31;161:413-418. Epub 2016 Aug 31.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China. Electronic address:

In this paper, a novel molecularly imprinted composite film modified electrode was presented for rutin (RT) detection. The modified electrode was fabricated by electropolymerization of pyrrole on a graphene-multiwalled carbon nanotubes composite (G-MWCNTs) coated glassy carbon electrode in the presence of RT. The netlike G-MWCNTs composite, prepared by in situ hydrothermal process, had high conductivity and electrocatalytic activity. At the resulting MIP/G-MWCNTs/GCE electrode RT could produce a sensitive anodic peak in pH 1.87 Britton-Robinson buffer solution. The factors affecting the electrochemical behavior and response of RT on the modified electrode were carefully investigated and optimized. Under the selected conditions, the linear response range of RT was 0.01-1.0μmolL and the detection limit (S/N=3) was 5.0nmolL. The electrode was successfully applied to the determination of RT in buckwheat tea and orange juice samples, and the recoveries for standards added were 93.4-105%.
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http://dx.doi.org/10.1016/j.talanta.2016.08.080DOI Listing
December 2016

Electrodeposition of self-assembled poly(3,4-ethylenedioxythiophene) @gold nanoparticles on stainless steel wires for the headspace solid-phase microextraction and gas chromatographic determination of several polycyclic aromatic hydrocarbons.

J Chromatogr A 2016 Nov 14;1471:80-86. Epub 2016 Oct 14.

Key laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Science, Wuhan University, Wuhan, Hubei 430072, PR China. Electronic address:

In this work, a novel poly(3,4-ethylenedioxythiophene)@Au nanoparticles ([email protected]) hybrid coating was prepared and characterized. Firstly, the monomer 3,4-ethylenedioxythiophene was self-assembled on AuNPs, and then electropolymerization was performed on a stainless steel wire by cyclic voltammetry. The obtained [email protected] coating was rough and showed cauliflower-like micro-structure with thickness of ∼40μm. It displayed high thermal stability (up to 330°C) and mechanical stability and could be used for at least 160 times of solid phase microextraction (SPME) without decrease of extraction performance. The coating exhibited high extraction capacity for some environmental pollutants (e.g. naphthalene, 2-methylnaphthalene, acenaphthene, fluorene and phenathrene) due to the hydrophobic interaction between the analytes and PEDOT and the additional physicochemical affinity between polycyclic aromatic hydrocarbons and AuNPs. Through coupling with GC detection, good linearity (correlation coefficients higher than 0.9894), wide linear range (0.01-100μgL), low limits of detection (2.5-25ngL) were achieved for these analytes. The reproducibility (defined as RSD) was 1.1-4.0% and 5.8-9.9% for single fiber (n=5) and fiber-to-fiber (n=5), respectively. The SPME-GC method was successfully applied for the determination of three real samples, and the recoveries for standards added were 89.9-106% for lake water, 95.7-112% for rain water and 93.2-109% for soil saturated water, respectively.
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http://dx.doi.org/10.1016/j.chroma.2016.10.041DOI Listing
November 2016

A Novel CuxO [email protected] Composite Derived from Core-Shell Metal-Organic Frameworks for Highly Selective Electrochemical Sensing of Hydrogen Peroxide.

ACS Appl Mater Interfaces 2016 Aug 28;8(31):20407-14. Epub 2016 Jul 28.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, Hubei Province, P. R. China.

A novel core-shell heterostructure of CuxO [email protected] imidazolate framework (CuxO [email protected]) was successfully prepared through facile pyrolysis of a nanocrystalline copper-based metal-organic framework [nHKUST-1, i.e., Cu3(BTC)2 (BTC = 1,3,5-benzene-tricarboxylate)]@ZIF-8, based on the different thermal stability of the two metal-organic frameworks (MOFs). The small CuxO NPs derived from nHKUST-1 were uniformly dispersed inside the host material and provided active sites, while ZIF-8 kept the original structure as the molecular sieving shell. Owing to the proper pore shape and pore size of ZIF-8, H2O2 could diffuse through the shell, but bigger molecules could not pass. Thus, the composite material exhibited high selectivity when it was used to construct a H2O2 sensor. In addition, the sensor showed an extended linear detection range (from 1.5 to 21442 μM), low detection limit (0.15 μM), and high sensitivity, due to the good electrocatalysis of CuxO NPs and the synergistic effect of the core-shell structure.
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http://dx.doi.org/10.1021/acsami.6b06436DOI Listing
August 2016
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