High density and uniform distribution of the gold nanoparticles functionalized single-stranded DNA modified reduced graphene oxide nanocomposites were obtained by non-covalent interaction.The positive gold nanoparticl...High density and uniform distribution of the gold nanoparticles functionalized single-stranded DNA modified reduced graphene oxide nanocomposites were obtained by non-covalent interaction.The positive gold nanoparticles prepared by phase inversion method exhibited good dimensional homogeneity and dispersibility,which could readily combine with single-stranded DNA modified reduced graphene oxide nanocomposites by electrostatic interactions.The modification of single-stranded DNA endowed the reduced graphene oxide with favorable biocompatibility and provided the preferable surface with negative charge for further assembling of gold nanoparticles to obtain gold nanoparticles/single-stranded DNA modified reduced graphene oxide nanocomposites with better conductivity,larger specific surface area,biocompatibility and electrocatalytic characteristics.The as-prepared nanocomposites were applied as substrates for the construction of cholesterol oxidase modified electrode and well realized the direct electron transfer between the enzyme and electrode.The modified gold nanoparticles could further catalyze the products of cholesterol oxidation catalyzed by cholesterol oxidase,which was beneficial to the enzyme-catalyzed reaction.The as-fabricated bioelectrode exhibited excellent electrocatalytic performance for the cholesterol with a linear range of 7.5–280.5μmol·L^(−1),a low detection limit of 2.1μmol·L^(−1),good stability and reproducibility.Moreover,the electrochemical biosensor showed good selectivity and acceptable accuracy for the detection of cholesterol in human serum samples.展开更多
Bienzymatic biosensor for the determination of glucose by flow injection chemiluminescence(CL) de-tection was proposed.Hybrids of gold nanoparticles(GNPs) and chitosan were chosen as the immobi-lization matrix of gluc...Bienzymatic biosensor for the determination of glucose by flow injection chemiluminescence(CL) de-tection was proposed.Hybrids of gold nanoparticles(GNPs) and chitosan were chosen as the immobi-lization matrix of glucose oxidase(GOD) and horseradish peroxidase(HRP) to fabricate the biosensors with silane-pretreated glass microbeads.After the enzyme catalyzing oxidation of glucose in GOD biosensor,the produced H2O2 flowed into HRP biosensor to react with luminol.The doped GNPs in chitosan were found to enhance the classical CL reaction of luminol-H2O2-HRP.The CL enhancement was investigated in detail by CL and UV-visible spectrum.Under the optimized experimental conditions,glucose could be determined in a linear range from 0.01 to 6.0 mmol/L with a detection limit of 5.0 μmol/L at 3σ.The accuracy of the proposed method was examined by detecting the glucose level in four clinical serum samples from hospital.The proposed method provides a new alternative to deter-mine glucose.展开更多
Rapid and accurate detection of glucose is of great significance for diabetic management.Highly sensitive glucose sensors promise to achieve noninvasive detection technology,enabling more convenient and efficient mean...Rapid and accurate detection of glucose is of great significance for diabetic management.Highly sensitive glucose sensors promise to achieve noninvasive detection technology,enabling more convenient and efficient means for large-scale screening and long-term dynamic monitoring of diabetes patients.In this work,we demonstrate a sensitive glucose electrochemical biosensor through the synergetic labelling strategy utilizing PbS colloidal quantum dots(CQDs)and Au nanospheres(AuNSs).The PbS CQDs/AuNSs/glucose oxidase(GOx)mixture could be stably immobilized on the carbon electrode surface via the onestep dip-coating method.The electrochemical biosensor employing PbS CQDs/AuNSs/GOx-modified electrode integrates the functions of specific molecule recognition,signal transduction as well as signal amplification.The sensor is capable of transducing the glucose enzyme-catalyzed reaction into significant current signals,exhibiting a good linear response in the glucose concentration range of 0.1μM-10 mM with the limit of detection being 1.432 nM.展开更多
Diabetes,one of the most serious metabolism diseases,has continually plagued human beings so that timely monitored blood glucose level is very necessary.Gold nanoparticles(Au NPs)have been considered as potential subs...Diabetes,one of the most serious metabolism diseases,has continually plagued human beings so that timely monitored blood glucose level is very necessary.Gold nanoparticles(Au NPs)have been considered as potential substitutes for non-enzymatic sensors,due to their unusual physicochemical property and efficient catalytic activity.Herein,we prepared a facial platform for Au NPs to maintain good dispersity and inherent physicochemical property.In this special platform(SH-n GO-PEG-Rh B),nanographene oxide(n GO)was employed as an ideal base,which provided adequate carboxyls for conjugating with poly(ethylene glycol)(PEG),and enough epoxy groups for thiol active site.A functional dye(rhodamine B)with preferable fluorescence properties was also introduced into this platform.Au NPs were then aptly in situ grown on the platform via reduction of HAuCl_(4) under mild conditions,providing Au NPs@SHn GO-PEG-Rh B.The nanocomposite was cast on a glassy carbon electrode(GCE)conveniently,yielding GCE/Au NPs@SH-n GO-PEG-Rh B.Reasonably,as shown by cyclic voltammetry(CV)and ready-state amperometry,GCE/Au NPs@SH-n GO-PEG-Rh B was capable of electrochemical determination of glucose so as to provide an efficient sensor for glucose determination with dye tracer.展开更多
基金support from the National Natural Science Foundation of China(Grant Nos.51773085,52071171)the Liaoning Province Doctor Start-up Fund(Grant No.20170520282)+8 种基金the Doctor Start-up Fund of Liaoning University(Grant No.a280008020)research fund pre-declaration project of Liaoning University(Grant No.LDGY2019001)teaching reform research project of Liaoning University(Grant Nos.JG2018YB20,LNDXJG20183013,JG2020ZSWT022)Liaoning Revitalization Talents Program-Pan Deng Scholars(Grant No.XLYC1802005)Liaoning BaiQianWan Talents Program(Grant No.LNBQW2018B0048)Natural Science Fund of Liaoning Province for Excellent Young Scholars(Grant No.2019-YQ-04)Key Project of Scientific Research of the Education Department of Liaoning Province(Grant No.LZD201902)the Young Scientific and Technological Talents Project of the Department of Education of Liaoning Province(Grant Nos.LQN201903 and LQN202008)the Foundation for Young Scholars of Liaoning University(Grant No.LDQN2019007).
文摘High density and uniform distribution of the gold nanoparticles functionalized single-stranded DNA modified reduced graphene oxide nanocomposites were obtained by non-covalent interaction.The positive gold nanoparticles prepared by phase inversion method exhibited good dimensional homogeneity and dispersibility,which could readily combine with single-stranded DNA modified reduced graphene oxide nanocomposites by electrostatic interactions.The modification of single-stranded DNA endowed the reduced graphene oxide with favorable biocompatibility and provided the preferable surface with negative charge for further assembling of gold nanoparticles to obtain gold nanoparticles/single-stranded DNA modified reduced graphene oxide nanocomposites with better conductivity,larger specific surface area,biocompatibility and electrocatalytic characteristics.The as-prepared nanocomposites were applied as substrates for the construction of cholesterol oxidase modified electrode and well realized the direct electron transfer between the enzyme and electrode.The modified gold nanoparticles could further catalyze the products of cholesterol oxidation catalyzed by cholesterol oxidase,which was beneficial to the enzyme-catalyzed reaction.The as-fabricated bioelectrode exhibited excellent electrocatalytic performance for the cholesterol with a linear range of 7.5–280.5μmol·L^(−1),a low detection limit of 2.1μmol·L^(−1),good stability and reproducibility.Moreover,the electrochemical biosensor showed good selectivity and acceptable accuracy for the detection of cholesterol in human serum samples.
基金Supported by the Natural Science Foundation of Shandong Province (Grant No. Q2007B03)the Doctoral Fund of Qingdao University of Science and Technology (Grant No. 0022141)the National Natural Science Foundation of China (Grant No. 20775038)
文摘Bienzymatic biosensor for the determination of glucose by flow injection chemiluminescence(CL) de-tection was proposed.Hybrids of gold nanoparticles(GNPs) and chitosan were chosen as the immobi-lization matrix of glucose oxidase(GOD) and horseradish peroxidase(HRP) to fabricate the biosensors with silane-pretreated glass microbeads.After the enzyme catalyzing oxidation of glucose in GOD biosensor,the produced H2O2 flowed into HRP biosensor to react with luminol.The doped GNPs in chitosan were found to enhance the classical CL reaction of luminol-H2O2-HRP.The CL enhancement was investigated in detail by CL and UV-visible spectrum.Under the optimized experimental conditions,glucose could be determined in a linear range from 0.01 to 6.0 mmol/L with a detection limit of 5.0 μmol/L at 3σ.The accuracy of the proposed method was examined by detecting the glucose level in four clinical serum samples from hospital.The proposed method provides a new alternative to deter-mine glucose.
基金supported by the National Natural Science Foundation of China(Nos.61922032 and 62205118).
文摘Rapid and accurate detection of glucose is of great significance for diabetic management.Highly sensitive glucose sensors promise to achieve noninvasive detection technology,enabling more convenient and efficient means for large-scale screening and long-term dynamic monitoring of diabetes patients.In this work,we demonstrate a sensitive glucose electrochemical biosensor through the synergetic labelling strategy utilizing PbS colloidal quantum dots(CQDs)and Au nanospheres(AuNSs).The PbS CQDs/AuNSs/glucose oxidase(GOx)mixture could be stably immobilized on the carbon electrode surface via the onestep dip-coating method.The electrochemical biosensor employing PbS CQDs/AuNSs/GOx-modified electrode integrates the functions of specific molecule recognition,signal transduction as well as signal amplification.The sensor is capable of transducing the glucose enzyme-catalyzed reaction into significant current signals,exhibiting a good linear response in the glucose concentration range of 0.1μM-10 mM with the limit of detection being 1.432 nM.
基金the financial support from National Science Fund for Distinguished Young Scholars(No.51825304)National Natural Science Foundation of China(No.52103094)+2 种基金Science and Technology Commission of Shanghai Municipality(Nos.20ZR1452200 and 22S31902900)Program for Outstanding Medical Academic Leader(No.2019LJ27)Shanghai Medical Key Specialty(No.ZK2019B12)。
文摘Diabetes,one of the most serious metabolism diseases,has continually plagued human beings so that timely monitored blood glucose level is very necessary.Gold nanoparticles(Au NPs)have been considered as potential substitutes for non-enzymatic sensors,due to their unusual physicochemical property and efficient catalytic activity.Herein,we prepared a facial platform for Au NPs to maintain good dispersity and inherent physicochemical property.In this special platform(SH-n GO-PEG-Rh B),nanographene oxide(n GO)was employed as an ideal base,which provided adequate carboxyls for conjugating with poly(ethylene glycol)(PEG),and enough epoxy groups for thiol active site.A functional dye(rhodamine B)with preferable fluorescence properties was also introduced into this platform.Au NPs were then aptly in situ grown on the platform via reduction of HAuCl_(4) under mild conditions,providing Au NPs@SHn GO-PEG-Rh B.The nanocomposite was cast on a glassy carbon electrode(GCE)conveniently,yielding GCE/Au NPs@SH-n GO-PEG-Rh B.Reasonably,as shown by cyclic voltammetry(CV)and ready-state amperometry,GCE/Au NPs@SH-n GO-PEG-Rh B was capable of electrochemical determination of glucose so as to provide an efficient sensor for glucose determination with dye tracer.
