Publications by authors named "Dongxue Han"

99 Publications

Effects of methyl cellulose and soybean protein isolate coating on oil content and chemical hazards of Chinese fried dough cakes.

J Food Prot 2021 Mar 26. Epub 2021 Mar 26.

Guangzhou University.

The increase in fat-related diseases and chemical hazards produced during the frying process poses a major threat to human health. Coating has been used as a practical method to reduce the oil content and chemical hazard of fried foods. Methyl cellulose (MC) and soy protein isolate (SPI) were used as coating materials to pretreat Chinese fried dough cake (CFDC) before frying. The results showed that 1.5% MC was the best choice for coating to simultaneously balance a low oil content and low chemical hazard content of CFDC. The CFDC prepared using the 1.5% MC content had the following components: an oil content of 11.3%, an acrylamide value of 73.70 μg/kg, an acid value of 0.15 mg KOH/100 kg, a peroxide value of 8.54 mmol/kg, a p-anisidine value of 6.36, a malondialdehyde content of 0.36 μg/g, a 4-hydroxy-2-(E)-hexenal content of 0.13 μg/g, a 4-hydroxy-2-(E)-nonenal content of 0.51 μg/g, and a glycidyl ester content of 4272 μg/kg. MC and SPI enhanced the oil barrier of the coating film, which effectively reduced the heat transfer coefficients, oil content, oil oxidation and chemical hazard in the CFDC. Our work contributes to the final control of oil content and chemical hazard in fried food by applying an edible coating.
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http://dx.doi.org/10.4315/JFP-21-062DOI Listing
March 2021

FRET Modulated Signaling: A Versatile Strategy to Construct Photoelectrochemical Microsensors for in Vivo Analysis.

Angew Chem Int Ed Engl 2021 Mar 2. Epub 2021 Mar 2.

Guangzhou University, School of Chemistry and Chemical Engineering, CHINA.

Microelectrode-based electrochemical (EC) and photoelectrochemical (PEC) sensors are promising candidates for in vivo analysis of biologically important chemicals. However, limited selectivity in complicated biological systems and poor adaptability to electrochemically non-active species restrained their applications. Herein, we propose the concept of modulating the PEC output by a fluorescence resonance energy transfer (FRET) process. The emission of energy donor was dependent on the concentration of target SO2, which in turn served as the modulator of the photocurrent signal of the photoactive material. The employment of optical modulation circumvented the problem of selectivity, and the as-fabricated PEC microelectrode showed good stability and reproducibility in vivo. It was able to monitor fluctuations of SO2 levels in brains of rat models of cerebral ischemia-reperfusion and febrile seizure. More significantly, such a FRET modulated signaling strategy can be extended to diverse analytes.
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http://dx.doi.org/10.1002/anie.202101468DOI Listing
March 2021

Palladium-modified cuprous(i) oxide with {100} facets for photocatalytic CO reduction.

Nanoscale 2021 Feb 3;13(5):2883-2890. Epub 2021 Feb 3.

School of Civil Engineering c/o Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.

Using metal as a photohole capturer can promote the photoelectron of p-type copper(i) oxide (CuO) substrate for efficient carbon dioxide reduction. However, palladium-decorated CuO (CuO-Pd) is seldom reported due to their mismatching band arrangement. Herein, we have successfully established a matched band alignment between Pd nanoparticles and CuO with exposed {100} facets (100CuO). The high work function of 100CuO originating from T symmetry vibration facilitates the photohole transferring to Pd nanoparticles, which leads to a three-fold increase in the photocatalytic generation of carbon monoxide (100CuO-0.1Pd, 0.13 μmol g h) than that with pristine 100CuO (0.04 μmol g h). Besides, the incorporation of Pd can relieve the photocorrosion of 100CuO, thus promoting its photocatalytic stability. As a contrast, 111CuO (CuO exposed to {111} facets) with low-work function was also synthesized and no charge migration was observed between 111CuO and Pd species, which verified the important role of the crystal surface regulation. All experimental phenomena were certified by the crystal surface analysis and energy band structure construction. Moreover, CO adsorption capacity tests indicated that the incorporation of Pd is beneficial for the capture of CO molecules. We hope that this work to some extent will enrich the subject of photocatalytic CO reduction.
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http://dx.doi.org/10.1039/d0nr07703hDOI Listing
February 2021

Oxidized titanium carbide MXene-enabled photoelectrochemical sensor for quantifying synergistic interaction of ascorbic acid based antioxidants system.

Biosens Bioelectron 2021 Apr 7;177:112978. Epub 2021 Jan 7.

State Key Laboratory of Electroanalytical Chemistry, C/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China; University of Science and Technology of China, Hefei, 230026, China.

Antioxidants can protect organization from damage by scavenging of free radicals. When two kinds of antioxidants are consumed together, the total antioxidant capacity might be enhanced via synergistic interactions. Herein, we develop a simple, direct, and effective strategy to quantify the synergistic interaction between ascorbic acid (AA) and other different antioxidants by photoelectrochemical (PEC) technology. MXene TiC-TiO composites fabricated via hydrogen peroxide oxidation were applied as sensing material for the antioxidants interaction study. Under excitation of 470 nm wavelength, the photogenerated electrons transfer from the conduction band of TiO nanoparticles to the TiC layers, and the holes in TiO can oxidize antioxidants, leading to an enhanced photocurrent as the detection signal. This PEC sensor exhibits a good linear range to AA concentrations from 12.48 to 521.33 μM as well as obvious antioxidants capability synergism. In particular, the photocurrents of AA + gallic acid (GA) and AA + chlorogenic acid (CHA) mixtures at 476.19 μM increase 1.95 and 2.35 times respectively comparing with the sum of photocurrents of AA and GA or CHA. It is found that the synergistic effect is mainly depending on the fact that AA with the low redox potential (0.246 V vs NHE) can reduce other antioxidants radical to promote regeneration, improving the overall antioxidant performance. Moreover, it is proved that the greater redox potential of antioxidants, the more obvious the synergistic effect. In addition, the sensor was used to real sample assay, which provides available information towards food nutrition analysis, health products design and quality inspection.
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http://dx.doi.org/10.1016/j.bios.2021.112978DOI Listing
April 2021

Molecularly imprinted photo-electrochemical sensor for hemoglobin detection based on titanium dioxide nanotube arrays loaded with CdS quantum dots.

Talanta 2021 Mar 28;224:121924. Epub 2020 Nov 28.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering c/o School of Civil Engineering, Guangzhou University, Guangzhou, 510006, China; State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, CAS Center for Excellence in Nanoscience, Changchun Institute of Applied Chemistry, Changchun, 130022, China; University of Chinese Academy of Sciences, Beijing, 100039, China.

A novel molecularly imprinted photo-electrochemical sensor based on CdS/TiO nanocomposites was constructed for precisely detection of hemoglobin under visible light irradiation. CdS quantum dots were decorated on the surface of TiO nanorod arrays to form a heterojunction, which could enhance the charge-transfer efficiency for visible light and further increase the photo-generated current of the sensor. The molecularly imprinted polymer film assembled by dopamine monomer had achieved excellent performance for specifically binding with human hemoglobin. The hemoglobin bound on the sensor could catalyze the oxidation reaction of 4-chloro-1-naphthol by HO, generating insoluble product on the sensor surface and triggering an obviously decrease on photocurrent. The molecularly imprinted photo-electrochemical sensor exhibited excellent sensitivity, selectivity and stability for the detection of human hemoglobin. The sensor had a linear range from 0.01 to 100 ng mL with a detection limit of 0.53 pg/mL (S/N = 3). Furthermore, the sensor was successfully applied on the analysis of human hemoglobin in the urine samples.
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http://dx.doi.org/10.1016/j.talanta.2020.121924DOI Listing
March 2021

Review of the formation and influencing factors of food-derived glycated lipids.

Crit Rev Food Sci Nutr 2020 Dec 29:1-16. Epub 2020 Dec 29.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, China.

Glycated lipids are formed by a Maillard reaction between the aldehyde group of a reducing sugar with the free amino group of an amino-lipid. The formation and accumulation of glycated lipids are closely related to the prognosis of diabetes, vascular disease, and cancer. However, it is not clear whether food-derived glycated lipids pose a direct threat to the human body. In this review, potentially harmful effect, distribution, formation environment and mechanism, and determination and inhibitory methods of glycated lipids are presented. Future research directions for the study of food-derived glycated lipids include: (1) understanding their digestion, absorption, and metabolism in the human body; (2) expanding the available database for associated risk assessment; (3) relating their formation mechanism to food production processes; (4) revealing the formation mechanism of food-derived glycated lipids; (5) developing rapid, reliable, and inexpensive determination methods for the compounds in different foods; and (6) seeking effective inhibitors. This review will contribute to the final control of food-derived glycated lipids.
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http://dx.doi.org/10.1080/10408398.2020.1867052DOI Listing
December 2020

CdS/TiO Nanocomposite-Based Photoelectrochemical Sensor for a Sensitive Determination of Nitrite in Principle of Etching Reaction.

Anal Chem 2021 01 15;93(2):820-827. Epub 2020 Dec 15.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering c/o School of Civil Engineering, Guangzhou University, Guangzhou 510006, P. R. China.

The CdS/TiO nanocomposite (NC) photoelectrochemical (PEC) sensor was constructed based on a new sensing strategy for nitrite assay. The CdS etching process caused by nitrite-in-acid solution was confirmed and applied to nitrite sensing. The CdS etching phenomenon occurring on the sensor led to an obvious reduction in the photocurrent response under visible-light irradiation, which responded to the nitrite concentration. The CdS/TiO NC-based PEC sensor exhibited excellent performance on nitrite detection. The linear range for nitrite determination was from 1-100 and 100-500 μM, and the sensitivity of the PEC sensor was 2.91 and 0.186 μA μM cm, respectively. The detection limit of the sensor was 0.56 μM (S/N = 3). In addition, the PEC sensor was also equipped with advantages such as good selectivity, excellent stability, low background, and recyclability. Satisfying results were obtained for the nitrite assay in real samples by such a PEC sensor. In summary, this work contributed a fresh idea to precisely determinate nitrite through PEC sensing.
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http://dx.doi.org/10.1021/acs.analchem.0c03315DOI Listing
January 2021

The inhibitory effects of sesamol and sesamolin on the glycidyl esters formation during deodorization of vegetables oils.

J Sci Food Agric 2020 Dec 4. Epub 2020 Dec 4.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, China.

Background: Glycidyl esters (GEs) have attracted worldwide attention for their potential harm to human health. The GEs in edible oils mainly form during the deodorization of the oil refining processes. We used sesamol and sesamolin to inhibit the formation of GEs in model corn oil (MCO), model palm oil (MPO) and model rice bran oil (MRO) during a deodorization process.

Results: The results showed that, in the three model oils, the total GE content was in the following order from highest to lowest: MRO (1437.98 μg kg ) > MPO (388.64 μg kg ) > MCO (314.81 μg kg ). The inhibitory effect of the three antioxidants on the formation of GEs in the MCO was in the following order from strongest to weakest: tert-butylhydroquinone (TBHQ) > sesamol > sesamolin.

Conclusion: When the mass percentage of sesamol was 0.05%, its inhibition percentage on GEs was close to the inhibition percentage of 0.02% added TBHQ. The present study provides a foundation for understanding how to inhibit the formation of GEs in oils by adding sesamol during the deodorization process.
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http://dx.doi.org/10.1002/jsfa.10989DOI Listing
December 2020

Electrochemically Controlled ATRP for Cleavage-Based Electrochemical Detection of the Prostate-Specific Antigen at Femtomolar Level Concentrations.

Anal Chem 2020 12 22;92(24):15982-15988. Epub 2020 Nov 22.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.

As a single-chain glycoprotein with endopeptidase activity, the prostate-specific antigen (PSA) is valuable as an informative serum marker in diagnosing, staging, and prognosis of prostate cancer. In this report, an electrochemical biosensor based on the target-induced cleavage of a specific peptide substrate (PSA peptide) is designed for the highly selective detection of PSA at the femtomolar level, using electrochemically controlled atom transfer radical polymerization (eATRP) as a method for signal amplification. The PSA peptides, without free carboxyl sites, are attached to the gold surface via the -terminal cysteine residue. The target-induced cleavage of PSA peptides results in the generation of carboxyl sites, to which the alkyl halide initiator α-bromophenylacetic acid (BPAA) is linked via the Zr(IV) linkers. Subsequently, the potentiostatic eATRP of ferrocenylmethyl methacrylate (FcMMA, as the monomer) leads to the surface-initiated grafting of high-density ferrocenyl polymers. As a result, a large amount of Fc redox tags can be recruited for signal amplification, through which the limit of detection (LOD) for PSA can be down to 3.2 fM. As the recognition element, the PSA peptide is easy to synthesize, chemically and thermally stable, and low-cost. Without the necessity of enzyme or nanoparticle labels, the eATRP-based amplification method is easy to operate and low-cost. Results also show that the cleavage-based electrochemical PSA biosensor is highly selective and applicable to PSA detection in complex biological samples. In view of these merits, the integration of the eATRP-based amplification method into cleavage-based recognition is believed to hold great promise for the electrochemical detection of PSA in clinical applications.
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http://dx.doi.org/10.1021/acs.analchem.0c03467DOI Listing
December 2020

Carbon Nitride Quantum Dots Enhancing the Anodic Electrochemiluminescence of Ruthenium(II) Tris(2,2'-bipyridyl) via Inhibiting the Oxygen Evolution Reaction.

Anal Chem 2020 12 10;92(23):15352-15360. Epub 2020 Nov 10.

Engineering Laboratory for Modern Analytical Techniques, C/o State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.

Although electrochemiluminescence (ECL) has been developed significantly in the past few decades, ECL efficiency in aqueous solutions remains quite low. Determination of the energy losses and development of new ECL-enhancing strategies are still of great value. In this work, we discovered a detrimental nonradiation relaxation pathway by a concurrent oxygen evolution reaction (OER) process in a well-known ruthenium(II) tris(2,2'-bipyridyl) (Ru(bpy)) aqueous ECL system due to similar surface-sensitive characteristics, and for the first time, a chemical strategy was developed by which carbon nitride quantum dots (CNQDs) could inhibit the surface OER process, alleviate the energy losses by nonradiation relaxation, and enhance the anodic ECL of Ru(bpy). In the Ru(bpy)/CNQD system, CNQDs could enhance the anodic ECL of Ru(bpy) in a nitrogen stream (10-fold) and ambient air (161-fold). The luminous and nitrogen-rich CNQDs were also confirmed not to serve as ECL luminophores, anodic coreactants, or donor/acceptors in ECL. The coreactant-free Ru(bpy)/CNQD system possesses several advantages over the common coreactant ECL system, such as low dosage (100 μg/mL CNQDs), favorable regeneration capacity, etc. As an example, ECL on-off detection of dopamine utilizing the Ru(bpy)/CNQD system was also developed to show prospects in ECL sensing. Besides, CNQDs were introduced into the classical Ru(bpy)/CO coreactant ECL system, leading to suppressed OER and improved ECL signal. Overall, the proposed new ECL-enhancing strategy is promising for applicable ECL sensing, could be extended to other ECL luminophores with high oxidation potential, and enables an in-depth understanding of the ECL process and mechanism.
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http://dx.doi.org/10.1021/acs.analchem.0c02568DOI Listing
December 2020

Sequentially amplified circularly polarized ultraviolet luminescence for enantioselective photopolymerization.

Nat Commun 2020 Nov 9;11(1):5659. Epub 2020 Nov 9.

CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST), No. 11 ZhongGuanCun BeiYiTiao, Beijing, 100190, P.R. China.

Chiral optical materials based on circularly polarized luminescence (CPL) have emerged rapidly due to their feasible applications in diverse fields of research. However, limited to the small luminescence dissymmetry factor (g), real application examples have rarely been reported. Here, we present a complex system, which show intense circularly polarized ultraviolet luminescence (CPUVL) with large g value, enabling a chiral UV light triggered enantioselective polymerization. By integrating sensitized triplet-triplet annihilation upconversion and CPL, both visible-to-UV upconversion emission and upconverted circularly polarized ultraviolet luminescence (UC-CPUVL) were obtained in the systems, built of chiral annihilator R(S)-4,12-biphenyl[2,2]paracyclophane (R-/S-TP), and a thermally activated delayed fluorescence (TADF) sensitizer. After dispersing this upconversion system into room-temperature nematic liquid crystal, induced chiral nematic liquid crystal could significantly amplify the g value (0.19) of UC-CPUVL. Further, the UC-CPUVL emission has been used to trigger the enantioselective photopolymerization of diacetylene. This work paves the way for the further development of functional application of CPL active materials.
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http://dx.doi.org/10.1038/s41467-020-19479-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652877PMC
November 2020

A three-electrode integrated electrochemical platform based on nanoporous gold for the simultaneous determination of hydroquinone and catechol with high selectivity.

Analyst 2021 Jan;146(1):232-243

School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, P. R. China.

In this study, a novel three-electrode integrated electrochemical platform (TEIEP) has been designed and fabricated for the simultaneous detection of hydroquinone (HQ) and catechol (CC), in which nanoporous gold (NPG) served as the working electrode, and Pt particles and nanoporous Ag/AgCl served as the courter electrode and the reference electrode, respectively. Due to the remarkable catalytic activity of NPG, the TEIEP exhibits high selectivity and sensitivity towards HQ and CC determination with a distinct separation between the peaks for their coexistence. The oxidation peak current densities of HQ and CC were linear over the range of 0.2-100 μM with the detection limits of 0.083 μM (S/N = 3) for HQ and 0.119 μM (S/N = 3) for CC. Moreover, TEIEP has a satisfactory reproducibility and anti-interference ability, and can be used in real water sample analysis. This work undoubtedly provides a remarkable choice for catalytic materials and an integrated structure, and further a promising application prospect for developing novel sensors for on-site environmental monitoring.
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http://dx.doi.org/10.1039/d0an01746aDOI Listing
January 2021

Potential in paleoclimate reconstruction of modern pollen assemblages from natural and human-induced vegetation along the Heilongjiang River basin, NE China.

Sci Total Environ 2020 Nov 22;745:141121. Epub 2020 Jul 22.

Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China. Electronic address:

The relationships among modern pollen, vegetation, climate and human activities can help improving the reliability of reconstruction of past vegetation, regional climate and human activities based on fossil pollen records. We used a dataset of 114 surface soil pollen samples from natural vegetation (wetlands, forests and grasslands) and human-induced vegetation (farmlands and residences) along the Heilongjiang River basin in northeast China to explore the relationships among modern pollen, vegetation, climate and human activities. The results indicated that surface pollen assemblages differentiated modern vegetation well in natural and human-induced vegetation types. The wetlands were mainly composed of Cyperaceae, along with Artemisia, weeds Poaceae (<35 μm) and Sanguisorba. The forests were predominated by Pinus and Betula. Artemisia, weeds Poaceae (<35 μm) and Chenopodiaceae were the most important pollen taxa in grasslands. The farmlands were characterized by Artemisia, Aster, Chenopodiaceae, cereal Poaceae (>35 μm) and Taraxacum. The pollen assemblages of residences were composed of weeds Poaceae (<35 μm), Chenopodiaceae and Salix. Ordination analyses based on main pollen taxa and climatic variables were used to determine the relationships between pollen and climate, suggesting the surface pollen assemblages were primarily influenced by the mean annual temperature (Tann) in northeast China. The statistical performance of transfer function between pollen and Tann were well indicating the modern pollen assemblages could be reliably used in paleoclimate reconstruction in our study area. Furthermore, human-induced vegetation had high frequencies of human-companion pollen taxa, such as Chenopodiaceae, Aster, Taraxacum and cereal Poaceae (>35 μm). Pollen concentrations of human-induced vegetation were lower than natural vegetation types, which could be used as an indicator of human influence intensity.
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http://dx.doi.org/10.1016/j.scitotenv.2020.141121DOI Listing
November 2020

Electrochemically controlled grafting of polymers for ultrasensitive electrochemical assay of trypsin activity.

Biosens Bioelectron 2020 Oct 4;165:112358. Epub 2020 Jun 4.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, 510006, PR China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, PR China; Collaborative Innovation Center of Tumor Marker Detection Technology, Equipment and Diagnosis-Therapy Integration in Universities of Shandong, Shandong Province Key Laboratory of Detection Technology for Tumor Makers, School of Chemistry and Chemical Engineering, Linyi University, Linyi, 276005, PR China. Electronic address:

As one of the most important proteolytic enzymes, trypsin is useful as a reliable and specific biomarker for the diagnosis of pancreatitis and other pathological conditions. In this paper, a novel signal-on electrochemical biosensor based on the use of electrochemically controlled grafting of polymers as an amplification strategy is described for the ultrasensitive assay of trypsin activity. The carboxyl-group-free peptide, serving as the substrate for the recognition of trypsin, is first immobilized via its N-terminus. The tryptic cleavage of peptide substrate can generate a free carboxyl group at the C-terminus of the truncated peptide, to which through the carboxylate-Zr(IV)-carboxylate linkage the carboxyl-group-containing initiator for atom transfer radical polymerization (ATRP) can be conjugated. The subsequent surface-initiated grafting of polymers (SI-GOP) based on electrochemically controlled ATRP (eATRP), with ferrocenylmethyl methacrylate (FcMMA) as the monomer, can bring a large amount of Fc tags to electrode surface, resulting in the generation of a very high detection signal. The eATRP-based SI-GOP is easy to operate and low-cost as an amplification strategy. Under optimal conditions, the detection limit for trypsin activity can be down to 0.016 mU mL (~2.68 pM or ~0.064 ng mL). As the current signal increases with trypsin activity, this trypsin biosensor is less susceptible to false positives due to the signal-on mode. Moreover, it is highly selective and applicable to inhibitor screening and the assay of trypsin activity in the presence of complex biological matrices. Taking together, this electrochemical trypsin biosensor may hold great potential in diagnostic applications.
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http://dx.doi.org/10.1016/j.bios.2020.112358DOI Listing
October 2020

A cost-effective fluorescence biosensor for cocaine based on a "mix-and-detect" strategy.

Analyst 2020 Jul 27;145(13):4664-4670. Epub 2020 May 27.

College of Pharmacy, Guangdong Medical University, Dongguan 523000, P. R. China.

The efficient detection of illicit drugs such as cocaine continues to be important for the fight against drug trafficking. Herein, we report a one-step method for rapid and specific cocaine detection. The method is based on our finding that small-molecule Thioflavin T (ThT) can act as a fluorescence indicator, which can be bonded with the anti-cocaine aptamer (MNS-4.1) to generate an enhanced fluorescence signal. More interestingly, upon cocaine binding, the intercalated ThT can be replaced, causing a drastic fluorescence reduction. We further optimized the sequence of MNS-4.1 and a new anti-cocaine aptamer (coc.ap2-GC) was obtained. This aptamer showed a higher affinity to both ligands, which increased the ThT binding fluorescence intensity and showed the highest quenching efficiency. Based on the fluorescence change induced by competitive binding, cocaine detection could be accomplished by a "mix-and-detect" strategy within seconds. Such a label-free method exhibits high sensitivity to cocaine with a low detection limit of 250 nM. Moreover, the practical sample analysis (2.5% human urine and saliva) also exhibits good precision and high sensitivity.
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http://dx.doi.org/10.1039/d0an00675kDOI Listing
July 2020

Construction of Bimetallic Selenides Encapsulated in Nitrogen/Sulfur Co-Doped Hollow Carbon Nanospheres for High-Performance Sodium/Potassium-Ion Half/Full Batteries.

Small 2020 May 20;16(19):e1907670. Epub 2020 Apr 20.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering c/o School of Civil Engineering, Guangzhou University, Guangzhou, Guangdong, 510006, China.

Metallic selenides have been widely investigated as promising electrode materials for metal-ion batteries based on their relatively high theoretical capacity. However, rapid capacity decay and structural collapse resulting from the larger-sized Na /K greatly hamper their application. Herein, a bimetallic selenide (MoSe /CoSe ) encapsulated in nitrogen, sulfur-codoped hollow carbon nanospheres interconnected reduced graphene oxide nanosheets (rGO@MCSe) are successfully designed as advanced anode materials for Na/K-ion batteries. As expected, the significant pseudocapacitive charge storage behavior substantially contributes to superior rate capability. Specifically, it achieves a high reversible specific capacity of 311 mAh g at 10 A g in NIBs and 310 mAh g at 5 A g in KIBs. A combination of ex situ X-ray diffraction, Raman spectroscopy, and transmission electron microscopy tests reveals the phase transition of rGO@MCSe in NIBs/KIBs. Unexpectedly, they show quite different Na /K insertion/extraction reaction mechanisms for both cells, maybe due to more sluggish K diffusion kinetics than that of Na . More significantly, it shows excellent energy storage properties in Na/K-ion full cells when coupled with Na V (PO ) O F and PTCDA@450 °C cathodes. This work offers an advanced electrode construction guidance for the development of high-performance energy storage devices.
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http://dx.doi.org/10.1002/smll.201907670DOI Listing
May 2020

Amplified Electrochemical Biosensing of Thrombin Activity by RAFT Polymerization.

Anal Chem 2020 02 29;92(4):3470-3476. Epub 2020 Jan 29.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering , Guangzhou University , Guangzhou 510006 , P. R. China.

As a serine protease, thrombin is a pivotal component in coagulation cascade and has been frequently screened as an informative biomarker for the diagnosis of coagulation disorder-related diseases. Herein, a "signal-on" electrochemical biosensor is described for the highly sensitive and selective detection of thrombin activity, by exploiting a thrombin-specific substrate peptide (Tb peptide) as the recognition element and reversible addition-fragmentation chain transfer (RAFT) polymerization for signal amplification. Specifically, the carboxyl-group-free Tb peptides are self-assembled onto gold electrode surface via the N-terminal cysteine residue and are used for the specific recognition of thrombin molecules. After the proteolytic cleavage of the Tb peptides, the carboxyl-group-containing RAFT agents (4-cyano-4-(phenylcarbonothioylthio)pentanoic acid, CPAD) are tethered to the free carboxyl termini of the truncated peptide fragments via the carboxylate-zirconium-carboxylate chemistry. The subsequent RAFT polymerization leads to the grafting of a polymer chain from each proteolytically cleaved site, enabling the recruitment of a large number of electroactive ferrocene (Fc) tags to the electrode surface when ferrocenylmethyl methacrylate (FcMMA) is used as the monomer. Under optimal conditions, the detection limit of the described thrombin biosensor is as low as 2.7 μU mL (∼0.062 pM), with a linear response over the range of 10-250 μU mL ( = 0.997). Results also indicate that the biosensor is highly selective and applicable to the detection of thrombin activity in complex serum samples and the screening of thrombin inhibitors. The described biosensor is low-cost and relatively easy in preparation and thus shows great promise for the highly sensitive and selective detection of thrombin activity.
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http://dx.doi.org/10.1021/acs.analchem.9b05647DOI Listing
February 2020

Stability of the permafrost peatlands carbon pool under climate change and wildfires during the last 150 years in the northern Great Khingan Mountains, China.

Sci Total Environ 2020 Apr 7;712:136476. Epub 2020 Jan 7.

Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Shengbei Street 4888, 130102 Changchun, China. Electronic address:

Peatlands store one-third of the total global soil carbon (C.) despite covering only 3-4% of the global land surface. Most peatlands are distributed in mid-high latitude regions and are even in permafrost regions, are sensitive to climate change and are disturbed by wildfire. Although several studies have focused on the impact of historical climate change and regional human activities on the C. accumulation process in these peatlands, the impact of these factors on the stability of the C. pool remains poorly understood. Here, based on the Pb age-depth model, we investigated the historical variations of C. stability during the last 150 years for five typical peatlands in the northern Great Khingan Mountains (Northeast China), an area located in a permafrost region that is sensitive to climate change and to wildfires, which have clearly increased due to regional human activities. The results showed that low C. accumulation rates (CARs) and weakly C. stability in studied peatlands before 1900. While, the increasing anthropogenic wildfire frequency and the residual products (e.g. pyrogenic carbon) increased the CARs and C. stability in peatlands from 1900 to 1980. The mean July temperature is the most important climate factor for peatlands C. stability. After 1980, due to the low wildfire frequencies influenced by human policies, increasing temperatures and decreasing precipitation not only increased the CARs but also markedly increased the C. stability of the peatlands C. pool in the northern Great Khingan Mountains, especially after 2000.
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http://dx.doi.org/10.1016/j.scitotenv.2019.136476DOI Listing
April 2020

Controlled/"living" radical polymerization-based signal amplification strategies for biosensing.

J Mater Chem B 2020 04;8(16):3327-3340

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.

Controlled/"living" radical polymerization (CLRP) techniques, such as atom transfer radical polymerization (ATRP), reversible addition-fragmentation chain transfer (RAFT) polymerization, and their variants, have now emerged as a novel class of signal amplification strategies and they have attracted growing attention in biosensing of clinically relevant biomolecules. Through the CLRP-mediated de novo formation of polymer chains, a large amount of signaling probes (e.g., ferrocene) or functional groups (e.g., -NH2, -CHO, and -COOH) that are available for the subsequent introduction of signaling probes can be recruited in the sensing interfaces, outputting a high signal even in the presence of a low abundance of target analytes, thereby greatly improving the detection sensitivity. Compared with conventional strategies based on the use of either catalytic labels (e.g., natural enzymes, biomimetic catalysts, and electrocatalysts) or complex nanomaterials (e.g., surface-functionalized metal nanoparticles), CLRP-based signal amplification strategies have advantages of being low-cost, highly efficient, and relatively easy in operation. By virtue of these merits, CLRP-based signal amplification strategies show great promise for clinical applications and biomedical research studies. In this review, the advantages and disadvantages of various signal amplification strategies have been summarized. Following a brief introduction of the mechanisms of various CLRP techniques, a comprehensive overview of the applications of CLRP-based signal amplification strategies in biosensing of clinically relevant biomolecules such as nucleic acids, enzymes, and antigens is presented. Also discussed herein are the advantages and disadvantages of CLRP-based signal amplification strategies, which are believed to be instructive for their broad application in biosensing.
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http://dx.doi.org/10.1039/c9tb02419kDOI Listing
April 2020

Highly selective conversion of CO to CH on graphene modified chlorophyll Cu through multi-electron process for artificial photosynthesis.

Nanoscale 2019 Dec 26;11(47):22980-22988. Epub 2019 Nov 26.

Centre for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P.R. China. and State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China.

Artificial photosynthesis is a promising strategy for converting carbon dioxide into hydrocarbon fuels through solar energy as it is clean, economical and environmentally friendly. Herein, we developed a selective and stable photocatalyst for CO photocatalytic reduction into CH through a multi-electron transfer pathway without the external sacrificial regents. The core component of this composite catalyst was extracted from a silkworm excrement and modified to make chlorophyll Cu (Chl-Cu), which contained a porphyrin structure as an antenna for light absorption and a Cu cation as an active centre. We found that C hydrocarbons such as CH, CH, and CH tended to generate on chlorophyll-a/graphene. After substituting Mg with Cu cations in the centre of the porphyrin and modifying with graphene, only CH was detected in the 18 hours reaction. This photocatalyst presented an outstanding activity and selectivity for the photocatalytic CO reduction (CORR) with a CH yield rate at 68.23 μmol m h under visible light irradiation and an apparent quantum efficiency of 1.26% at 420 nm. In this system, the porphyrin rings were excited to produce electron-hole pairs by light. The photo-induced holes oxidized water to produce oxygen while graphene worked as an adsorption centre and electron acceptor for the CO reduction.
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http://dx.doi.org/10.1039/c9nr07824jDOI Listing
December 2019

N-Doped Graphene Oxide Decorated with PtCo Nanoparticles for Immobilization of Double-Stranded Deoxyribonucleic Acid and Investigation of Clenbuterol-Induced DNA Damage.

ACS Omega 2019 Oct 26;4(15):16524-16530. Epub 2019 Sep 26.

Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P.R. China.

We demonstrate here a facile hydrothermal-assisted formation of PtCo alloy nanoparticles (NPs) and their simultaneous anchoring on the graphitic surface of N-doped graphene oxide (NGO). Doping induced nanopores in the carbon surface to facilitate the uniform and homogeneous anchoring of alloy nanoparticles. It was revealed that the formation of PtCo NPs on an NGO interface plodded excellent tendency toward double-stranded deoxyribonucleic acid (dsDNA). The dsDNA immobilization was enabled by the presence of several oxidation states of Pt and Co. The same property was further used to monitor the direct detection of dsDNA damage induced by clenbuterol via screen-printed carbon electrodes. Cyclic voltammetric and electrochemical impedance spectroscopic characterization traced well the dsDNA attachment on the modified electrode surface. Differential pulsed voltammetry was further used as a tool to monitor the characteristic guanine peak before and after incubating with clenbuterol used as a damage probe for the dsDNA. The findings can further be appurtenant in exploring dsDNA immobilization protocols and developing analytical methods for determination of various dsDNA damaging agents.
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http://dx.doi.org/10.1021/acsomega.9b02184DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6788047PMC
October 2019

Ultrasensitive peptide-based electrochemical detection of protein kinase activity amplified by RAFT polymerization.

Talanta 2020 Jan 30;206:120173. Epub 2019 Jul 30.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, 510006, PR China; School of Civil Engineering, Guangzhou University, Guangzhou, 510006, PR China.

Since the oversecretion of protein kinases is indicative of multiple human diseases, the screening of their activities is quite important to clinical diagnosis and targeted therapy. In this work, an ultrasensitive peptide-based electrochemical biosensor was presented for the detection of protein kinase activity by using the reversible addition-fragmentation chain transfer (RAFT) polymerization technique as a signal amplification strategy. First, the substrate peptides were tethered to a gold electrode surface via the thiol terminals. After the phosphorylation of substrate peptides by protein kinases, the carboxyl group-containing dithiobenzoates were labeled to the phosphorylated sites via the robust phosphate-Zr-carboxylate linkages. Finally, the RAFT polymerization was initiated using ferrocenylmethyl methacrylates (FcMMAs) and dithiobenzoates as the monomers and the RAFT agents, respectively. The grafting of ferrocenyl polymer chains efficiently recruits a great number of electro-active Fc probes to each phosphorylated site, leading to a drastic amplification of the electrochemical signal. With PKA (protein kinase A) as the target, the detection limit of the peptide-based biosensor can be as low as 1.05 mU mL. Moreover, it can selectively differentiate the target from other interferents and is applicable for the screening of potential inhibitors as well as the detection of protein kinase activity in complex cell lysates. Therefore, the peptide-based biosensor shows great promise as a universal tool for protein kinase activity detection and inhibitor screening.
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http://dx.doi.org/10.1016/j.talanta.2019.120173DOI Listing
January 2020

Compactly Coupled Nitrogen-Doped Carbon Nanosheets/Molybdenum Phosphide Nanocrystal Hollow Nanospheres as Polysulfide Reservoirs for High-Performance Lithium-Sulfur Chemistry.

Small 2019 Oct 5;15(40):e1902491. Epub 2019 Aug 5.

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Changchun, 130022, Jilin, China.

Lithium-sulfur (Li-S) batteries have been disclosed as one of the most promising energy storage systems. However, the low utilization of sulfur, the detrimental shuttling behavior of polysulfides, and the sluggish kinetics in electrochemical processes, severely impede their application. Herein, 3D hierarchical nitrogen-doped carbon nanosheets/molybdenum phosphide nanocrystal hollow nanospheres (MoP@C/N HCSs) are introduced to Li-S batteries via decorating commercial separators to inhibit polysulfides diffusion. It acts not only as a polysulfides immobilizer to provide strong physical trapping and chemical anchoring toward polysulfides, but also as an electrocatalyst to accelerate the kinetics of the polysulfides redox reaction, and to lower the Li S nucleation/dissolution interfacial energy barrier and self-discharge capacity loss in working Li-S batteries, simultaneously. As a result, the Li-S batteries with MoP@C/N HCS-modified separators show superior rate capability (920 mAh g at 2 C) and stable cycling life with only 0.04% capacity decay per cycle over 500 cycles at 1 C with nearly 100% Coulombic efficiency. Furthermore, the Li-S battery can achieve a high area capacity of 5.1 mAh cm with satisfied capacity retention when the cathode loading reaches 5.5 mg cm . This work offers a brand new guidance for rational separator design into the energy chemistry of high-stable Li-S batteries.
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http://dx.doi.org/10.1002/smll.201902491DOI Listing
October 2019

Inhibition Mechanism of Catechin, Resveratrol, Butylated Hydroxylanisole, and Tert-Butylhydroquinone on Carboxymethyl 1,2-Dipalmitoyl-sn-Glycero-3-Phosphatidylethanolamine Formation.

J Food Sci 2019 Aug 17;84(8):2042-2049. Epub 2019 Jul 17.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou Univ., Guangzhou, 510006, China.

It is important to inhibit the food-derived, potentially hazardous chemical glycated lipids by natural products. A model system was established and the products are identified to study the inhibitory mechanism of four types of catechin, resveratrol (RES), and the synthetic antioxidants butylated hydroxylanisole (BHA) and tert-butylhydroquinone (TBHQ) on the formation of carboxymethyl 1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine (CM-DPPE) by determining hydroxyl radical (OH·), Amadori-1,2-dipalmitoyl-sn-glycero-3-phosphatidylethanolamine (Amadori-DPPE) and glyoxal (GO). The results show that the inhibitory rates of catechin and RES on the content of CM-DPPE in the model system are higher than those of BHA and TBHQ. There are at least two inhibitory mechanisms of antioxidants on CM-DPPE. (1) Antioxidants scavenge OH·, which blocks the process of Amadori-DPPE oxidation to form CM-DPPE. (2) Antioxidants trap GO, which blocks the reaction between GO and DPPE to form CM-DPPE. This research will reveal the inhibitory mechanisms of natural antioxidants on glycated lipids from the aspect of scavenging OH· and trapping GO. PRACTICAL APPLICATION: Food manufacturers should pay attention on the production of glycated lipids in food processing. This study will provide the theoretical basis for the use of natural products to inhibit the formation of food-derived glycated lipids. Natural products, such as catechin and resveratrol, can substitute chemical synthesis antioxidants, such as butylated hydroxylanisole and tert-butylhydroquinone, in food processing, which inhibit the formation of glycated lipids.
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http://dx.doi.org/10.1111/1750-3841.14668DOI Listing
August 2019

Lipids Promote Glycated Phospholipid Formation by Inducing Hydroxyl Radicals in a Maillard Reaction Model System.

J Agric Food Chem 2019 Jul 8;67(28):7961-7967. Epub 2019 Jul 8.

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering , Guangzhou University , Guangzhou 510006 , China.

Food-derived glycated phospholipids is potentially hazardous to human health. However, there are few studies on the effects of lipids on the formation of glycated phospholipids. In this work, two model systems were established: (1) a model system including 1,2-dipalmitoyl--glycero-3-phosphoethanolamine (PE), glucose, and Fenton reagent and (2) a model system including PE, glucose, and five kind of vegetable oils. The contents of carboxymethyl-PE, carboxyethyl-PE, Amadori-PE, hydroxyl radical (OH•), glyoxal, and methylglyoxal were determined with high-performance liquid chromatography mass spectrometry. The results of the first model system showed that OH• oxidized glucose to produce glyoxal and methylglyoxal, which then reacted with PE to form carboxymethyl-PE and carboxyethyl-PE. OH• also oxidized Amadori-PE to form carboxymethyl-PE. The results of the second model system showed that vegetable oils with higher number of moles of carbon-carbon unsaturated double bond in vegetable oil per kilogram could produce more OH•, which promote the formation of carboxymethyl-PE and carboxyethyl-PE by oxidizing glucose and oil. We elucidated the effects of oils on the formation of glycated phospholipids in terms of OH• and intermediates. This work will contribute to better understanding the formation mechanism of glycated phospholipids with oil.
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http://dx.doi.org/10.1021/acs.jafc.9b02771DOI Listing
July 2019

MoS/ZnO-Heterostructures-Based Label-Free, Visible-Light-Excited Photoelectrochemical Sensor for Sensitive and Selective Determination of Synthetic Antioxidant Propyl Gallate.

Anal Chem 2019 08 27;91(16):10657-10662. Epub 2019 Jun 27.

State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , China.

Propyl gallate (PG) as one of the important synthetic antioxidants is widely used in the prevention of oxidative deterioration of oils during processing and storage. Determination of PG has received extensive concern because of its possible toxic effects on human health. Herein, we report a photoelectrochemical (PEC) sensor based on ZnO nanorods and MoS flakes with a vertically constructed p-n heterojunction. In this system, the n-type ZnO and p-type MoS heterostructures exhibited much better optoelectronic behaviors than their individual materials. Under an open circuit potential (zero potential) and visible light excitation (470 nm), the PEC sensor exhibited extraordinary response for PG determination, as well as excellent anti-inference properties and good reproducibility. The PEC sensor showed a wide linear range from 1.25 × 10 to 1.47 × 10 mol L with a detection limit as low as 1.2 × 10 mol L. MoS/ZnO heterostructure with proper band level between MoS and ZnO could make the photogenerated electrons and holes separated more easily, which eventually results in great improvement of sensitivity. On the other hand, formation of a five membered chelating ring structure of Zn(II) with adjacent oxygen atoms of PG played significant roles for selective detection of PG. Moreover, the PEC sensor was successfully used for PG analysis in different samples of edible oils. It demonstrated the ability and reliability of the MoS/ZnO-based PEC sensor for PG detection in real samples, which is beneficial for food quality monitoring and reducing the risk of overuse of PG in foods.
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http://dx.doi.org/10.1021/acs.analchem.9b01889DOI Listing
August 2019

History metal (Pb, Zn, and Cu) deposition and Pb isotope variability in multiple peatland sites in the northern Great Hinggan Mountains, Northeast China.

Environ Sci Pollut Res Int 2019 Jul 27;26(21):21784-21796. Epub 2019 May 27.

Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Shengbei Street 4888, Changchun, 130102, China.

Placer gold mining is important anthropogenic sources of dust and metals that can strongly influence the environmental quality of the surrounding ecosystem. However, scarce studies have focused on evaluating the influence of placer gold mining on historical metal deposition in the surrounding ecosystem in the northern Great Hinggan Mountains, which is located at northeast of China. To address this research gap, four peatland cores with different distances to a gold placer in the northern Great Hinggan Mountains were selected in this study. Based on the Pb depth-age model, historical variations in the Pb isotope and deposition fluxes of Pb, Cu, and Zn were reconstructed. The results show that metal deposition in the northern Great Hinggan Mountains was mainly influenced by the placer gold mining around the 1900s when the gold placer started to produce gold, and placer gold mining more seriously influenced the western sites that were closer to the placer gold mining. With increasing global metal productions after 1930, the proportion of the metals from placer gold mining sources gradually decreased, and part of Pb were transported via the atmosphere from other regions (e.g., Europe, East Asia). With the implementation of environmentally friendly policies and the decreasing anthropogenic production of Pb, Cu, and Zn around the world, deposition fluxes of these metals in the northern Great Hinggan Mountain began to decrease after 2000.
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http://dx.doi.org/10.1007/s11356-019-04432-7DOI Listing
July 2019

Catechin inhibits glycated phosphatidylethanolamine formation by trapping dicarbonyl compounds and forming quinone.

Food Funct 2019 May;10(5):2491-2503

Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China.

It is important to inhibit food-derived potentially hazardous glycated lipids with natural products. A model reaction inhibition system was established, and products were identified with high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) to study the inhibitory effects of four types of catechins on the formation of glycated 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) products. The results show that the percentage inhibition of epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC) and epigallocatechin gallate (EGCG) on the formation of carboxymethyl 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (CM-DPPE) are 38.84%, 33.31%, 20.71% and 22.66%, respectively. The percentage inhibition of EC, ECG, EGC and EGCG on the formation of carboxyethyl 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (CE-DPPE) is 42.04%, 41.99%, 31.70% and 36.24%, respectively. In addition, catechin can capture glyoxal (GO) and methylglyoxal (MGO) to produce multiple products. O-Benzoquinone, the oxidation products of catechin, also captures DPPE to produce quinone-DPPE adducts. Therefore, there are two inhibitory mechanisms of tea-derived catechin for glycated DPPE: (1) catechin inhibits the formation of CM-DPPE and CE-DPPE by trapping reactive GO and MGO; and (2) catechin is oxidized to o-benzoquinone. O-Benzoquinone reacts with DPPE through nucleophilic substitution, which competes with the reaction between glucose and DPPE. This study will provide a theoretical basis for the use of natural products to inhibit the formation of food-derived glycated lipids.
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http://dx.doi.org/10.1039/c9fo00155gDOI Listing
May 2019

A nanocomposite prepared from magnetite nanoparticles, polyaniline and carboxy-modified graphene oxide for non-enzymatic sensing of glucose.

Mikrochim Acta 2019 04 2;186(5):267. Epub 2019 Apr 2.

Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad Lahore Campus, Lahore, 55150, Pakistan.

The authors report on the synthesis of carboxy functionalized graphene oxide (fGO) decorated with magnetite (FeO) nanoparticles. The resulting nanomaterial was used to prepare a composite with polyaniline (PANI) which was characterized by UV-vis, Fourier transform-infrared and Raman spectroscopies. Its surface morphologies were characterized by atomic force and scanning electron microscopies. A screen-printed carbon electrode was then modified with the nanocomposite to obtain an enzyme-free glucose sensor. The large surface of fGO and FeO along with the enhanced charge transfer capability of PANI warrant a pronounced electrochemical response (typically measured at 0.18 V versus Ag/AgCl) which is suppressed in the presence of glucose. This reduction of current by glucose was used to design a sensitive method for quantification of glucose. The response of the modified SPCE is linear in the 0.05 μM - 5 mM glucose concentration range, and the lower detection limit is 0.01 μM. Graphical abstract Schematic illustration of in-situ anchoring of Iron oxide on functionalized graphene oxide and synthesis of its polymeric nanocomposite for non-enzymatic detection of Glucose. The nanocomposite modified screen printed interface enabled monitoring of glucose at lower potential with higher precision. GO (graphene oxide), fGO (functionalized graphene oxide), PANI (polyaniline).
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http://dx.doi.org/10.1007/s00604-019-3364-2DOI Listing
April 2019

Chiral Nanostructured Composite Films via Solvent-Tuned Self-Assembly and Their Enantioselective Performances.

Langmuir 2019 03 18;35(9):3337-3345. Epub 2019 Feb 18.

Chiral nanostructures exhibited distinctive functions and attractive applications in complex biological systems, which demonstrated the subject of many outstanding research studies. In this work, various hierarchical composite film nanostructures were designed via supramolecular self-assembly using chiral amphiphilic glutamate derivatives and achiral porphyrin derivatives and their macroscopic enantioselective recognition properties were investigated. We have found that intermolecular hydrogen-bonding interactions between water (donor and acceptor) and N, N-dimethylformamide (DMF) as well as chloroform (CHCl) (acceptor only) and DMF could subtly alter the molecular packing and significantly affected the supramolecular self-assembled nanostructures and triggered circular dichroism (CD) signal reversal. Present research work exemplified a feasible method to fabricate chiral flower-like and brick-like nanostructure films in different mixed solvents and large-scale chiral transfer from the molecular level to complex structures, which also provided a facile approach to identify certain l-/d-amino acids by means of contact angle detection using present obtained self-assembled composted films.
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http://dx.doi.org/10.1021/acs.langmuir.9b00014DOI Listing
March 2019