A simple and sensitive platinum nanoparticles/poly（hydroxymethylated-3,4-ethylenedioxylthiophene） nanocomposite （PtNPs/PEDOT-MeOH） modified glassy carbon electrode （GCE） was successfully developed for the electr...A simple and sensitive platinum nanoparticles/poly（hydroxymethylated-3,4-ethylenedioxylthiophene） nanocomposite （PtNPs/PEDOT-MeOH） modified glassy carbon electrode （GCE） was successfully developed for the electrochemical determination of quercetin. Scanning electron microscopy and energy dispersive X-ray spectroscopy results indicated that the PtNPs were inserted into the PEDOT- MeOH layer. Compared with the bare GCE and poly（3,4-ethylenedioxythiophene） （PEDOT） electrodes, the PtNPs/PEDOT-MeOH/GCE modified electrode exhibited a higher electrocatalytic ability toward the oxidation of quercetin due to the synergic effects of the electrocatalytic activity and strong adsorption ability of PtNPs together with the good water solubility and high conductivity of PEDOT-MeOH. The electrochemical sensor can be applied to the quantification of quercetin with a linear range covering 0.04-91μmol L-1 and a low detection limit of 5.2 nmol L-1. Furthermore, the modified electrode also exhibited good reoroducibilitv and long-term stability, as well as high selectivity.展开更多
Au nanoparticles(AuNPs)were prepared by reducing HAuCl4 with NaBH4,and then adsorbed uniformly on the surface of carboxylated nanocrystalline cellulose(CNCC).The obtained AuNPs/CNCC particles were doped into a conduct...Au nanoparticles(AuNPs)were prepared by reducing HAuCl4 with NaBH4,and then adsorbed uniformly on the surface of carboxylated nanocrystalline cellulose(CNCC).The obtained AuNPs/CNCC particles were doped into a conductive polymer of poly(3,4-ethylenedioxythiophene)(PEDOT)to yield a highly conductive nanocomposite,which was deposited onto a glassy carbon electrode(GCE)by an electrochemical method.The PEDOT/AuNPs/CNCC nanocomposite showed low electrochemical impedance and good electrocatalytic activity toward ascorbic acid.Based on this novel nanocomposite material,an amperometric sensor was developed for the detection of ascorbic acid with a detection limit as low as 0.29μM.When operated at-0.15 V,the sensor detected ascorbic acid in the range of 0.88μM to 15000μM.展开更多
A rapid and sensitive method for analyzing trace b-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron resonance mass spectrometry(FT...A rapid and sensitive method for analyzing trace b-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron resonance mass spectrometry(FTICR-MS),was developed.Novel nanosilver-functionalized magnetic nanoparticles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace b-blockers from biological samples.After extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS.The method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,respectively.The accuracy of the method was also desirable,with recoveries ranging from 80.9%to 91.0%following the detection of analytes in human blood samples.All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace b-blockers in complex biological samples.展开更多
Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammo...Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammonia solution and subsequent coating with 3,4-dihydroxylaldehyde. Magnetic Fe304 nanoparticles modified with 3,4-dihydroxylaldehyde bonded lipase efficiently（47 mg/g）. The resulting magnetic-lipase is active（0.68 μmol·min^-1·mg^-1） and enantioselective（e.e, of the product 〉98%） in the hydrolysis of racemic 1-phenylethyl acetate. Furthermore, as a heterogeneous catalyst, the magnetic-lipase can be magnetically recycled, and a retained activity of 48% was obtained even after 6 cycles.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51263010 and 51272096)Jiangxi Provincial Department of Education(No.GJJ11590)+1 种基金Natural Science Foundation of Jiangxi Province(No.2010GZH0041)Graduate Student Innovation Foundation of Jiangxi Province(No.YC2012-S123)
文摘A simple and sensitive platinum nanoparticles/poly（hydroxymethylated-3,4-ethylenedioxylthiophene） nanocomposite （PtNPs/PEDOT-MeOH） modified glassy carbon electrode （GCE） was successfully developed for the electrochemical determination of quercetin. Scanning electron microscopy and energy dispersive X-ray spectroscopy results indicated that the PtNPs were inserted into the PEDOT- MeOH layer. Compared with the bare GCE and poly（3,4-ethylenedioxythiophene） （PEDOT） electrodes, the PtNPs/PEDOT-MeOH/GCE modified electrode exhibited a higher electrocatalytic ability toward the oxidation of quercetin due to the synergic effects of the electrocatalytic activity and strong adsorption ability of PtNPs together with the good water solubility and high conductivity of PEDOT-MeOH. The electrochemical sensor can be applied to the quantification of quercetin with a linear range covering 0.04-91μmol L-1 and a low detection limit of 5.2 nmol L-1. Furthermore, the modified electrode also exhibited good reoroducibilitv and long-term stability, as well as high selectivity.
基金supported by the National Natural Science Foundation of China(21422504 and 21275087)the Natural Science Foundation of Shandong Province of China(JQ201406).
文摘Au nanoparticles(AuNPs)were prepared by reducing HAuCl4 with NaBH4,and then adsorbed uniformly on the surface of carboxylated nanocrystalline cellulose(CNCC).The obtained AuNPs/CNCC particles were doped into a conductive polymer of poly(3,4-ethylenedioxythiophene)(PEDOT)to yield a highly conductive nanocomposite,which was deposited onto a glassy carbon electrode(GCE)by an electrochemical method.The PEDOT/AuNPs/CNCC nanocomposite showed low electrochemical impedance and good electrocatalytic activity toward ascorbic acid.Based on this novel nanocomposite material,an amperometric sensor was developed for the detection of ascorbic acid with a detection limit as low as 0.29μM.When operated at-0.15 V,the sensor detected ascorbic acid in the range of 0.88μM to 15000μM.
基金supported by the National Natural Science Foundation of China(Grant Nos.:21976168,22127810,and 22004113)Key Research and Development Program of Guangdong Province(Grant No.:2020B1111350002)+1 种基金Guangdong Basic and Applied Basic Research Foundation(Grant No.:2019A1515110420)GDAS0 Project of Science and Technology Development(Grant No.:2021GDASYL-20210103034).
文摘A rapid and sensitive method for analyzing trace b-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron resonance mass spectrometry(FTICR-MS),was developed.Novel nanosilver-functionalized magnetic nanoparticles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace b-blockers from biological samples.After extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS.The method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,respectively.The accuracy of the method was also desirable,with recoveries ranging from 80.9%to 91.0%following the detection of analytes in human blood samples.All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace b-blockers in complex biological samples.
基金Supported by the National Natural Science Foundation of China（No.21203017）, the Open Fund of State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences（No.N-11-3）, the Program for Liaoning Excellent Talents in University, China and the Fundamental Research Funds for the Central Universities, China（No.DC201502020304）.
文摘Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammonia solution and subsequent coating with 3,4-dihydroxylaldehyde. Magnetic Fe304 nanoparticles modified with 3,4-dihydroxylaldehyde bonded lipase efficiently（47 mg/g）. The resulting magnetic-lipase is active（0.68 μmol·min^-1·mg^-1） and enantioselective（e.e, of the product 〉98%） in the hydrolysis of racemic 1-phenylethyl acetate. Furthermore, as a heterogeneous catalyst, the magnetic-lipase can be magnetically recycled, and a retained activity of 48% was obtained even after 6 cycles.
