Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay ...Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay of SEB was developed.The probe(Ab2/AuPt@Fe-N-C)was bound to SEB captured by Ab1,where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical signal.Furthermore,the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 nm.Once the target was captured and formed a sandwich-like complex,the color changed from colorless to blue.SEB detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.0002-10.0000 and 0.0005-10.0000 ng/mL,with limits of detection of 0.0667 and 0.1670 pg/mL,respectively.The dual-signal biosensor was successfully used to detect SEB in milk and water samples,which has great potential in toxin detection in food and the environment.展开更多
The electrochemical immunosensor for a-fetoprotein (AFP) was fabricated based on the platform of gold nanoparticles (GNP)/graphene (Gr)-prussian blue (PB). By electrodeposition, GNP were modified on the surfac...The electrochemical immunosensor for a-fetoprotein (AFP) was fabricated based on the platform of gold nanoparticles (GNP)/graphene (Gr)-prussian blue (PB). By electrodeposition, GNP were modified on the surface of the prepared Gr-PB. The anti-AFP-1, l'-ferrocenedicarboxylic acid (FcDA) as label was directly immobilized on the platform of GNP/Gr-PB. And after the immunoreactions, the formed complex inhibited the electron transfer and decreased the catalytic current of FcDA toward the reduction of H2O2. And in the range of 10-3200 pgomL^-1, the decreased current is linear with the concentration of AFP, with a detection limit of 3 pg.mL-1. The developed im- munoassay method showed good precision, high sensitivity, acceptable stability and reproducibility, and could be used for the detection of real samples with consistent results in comparison with those obtained by the enzyme linked immunosorbent assay (ELISA) method.展开更多
A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles(PTh-Au) modified glassy carbon electrode(GCE) as a platform and secondary antibody labeled Au NPs...A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles(PTh-Au) modified glassy carbon electrode(GCE) as a platform and secondary antibody labeled Au NPs(Ab;-Au) as immumoprobe for carcinoembryonic antigen(CEA) detection. The sandwich-type biosensor adopted anodic stripping voltammetry to detect silver stripping signal when the Ab;-Au of the formed immunocomplexes were stained with silver. The optimized detection conditions were investigated. The effect of different electrochemical responses at various concentrations of CEA was checked by anodic stripping voltammetry. This immunosensor showed a low detection limit of 0.055 ng/mL and a wide linear calibration of 0.1-120 ng/mL(R;=0.99856). Moreover, this immunoassay also existed the advantages of good reproducibility, stability and selectivity. Thus, this immunosensing protocol may provide a potential application for effective clinical detection of CEA.展开更多
In this study, a novel layer-by-layer polyaniline/graphene (PANi/Gr) structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition (CVD) method a...In this study, a novel layer-by-layer polyaniline/graphene (PANi/Gr) structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition (CVD) method and transferred onto the PANi-predeposited microelectrode. The properties of PANi/Gr film were thoroughly investigated by high-resolution transmission electron microscopy and Raman techniques. The most attractive feature of this system is a suitable microenvironment, which could provide an amplifi- cation of the conductive signal, thus may contribute to enhancing electron transfer and subsequently improve the sensitivity in electrochemical measurements. With low detection limit (- 43 × 10 -12 g/L), ac-ceptable stability and good reproducibility, the proposed electrochemical immunosensor could be advantageously extended for multiplexed detection of other agents of environmental pollution.展开更多
Interferon-γis a kind of protein with a wide range of biological activities,which can regulate the immune function of the body,and can be used as an important marker to detect and treat bovine tuberculosis diseases.H...Interferon-γis a kind of protein with a wide range of biological activities,which can regulate the immune function of the body,and can be used as an important marker to detect and treat bovine tuberculosis diseases.Here,a picogram-level bovine interferon-γ(BoIFN-γ)electrochemical impedance immunosensor was constructed for the first time using mesoporous silica nanospheres(MS Ns)to immobilize specific monoclonal BoIFN-y antibodies.The MS Ns and BoIFN-γimmuno sensors were characterized using scanning electron microscopy,transmission electron microscope,nitrogen adsorption experiment,X-ray photoelectron spectra,and contact angle measurements.MSNs possess a substantial specific surface area and significant hydrophilicity,and can immobilize many antibody molecules,thereby improving detection sensitivity.The immunosensor has a linear detection range from 0.001 to 10.0 ng/mL with an exceptionally low detection limit of 0.62 pg/mL.Compared to the traditional BoIFN-γanalysis method,BoIFN-γimmunosensor presents superiorities in sensitivity,wide linear range as well as short processing time.More importantly,the BoIFN-γsensor exhibits high selectivity,reliable repeatability as well as stability,providing a promising application prospect for the early diagnosis of Mycobacterium bovis infection.展开更多
It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety...It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety.Taking the advantages of ultrahigh electron-transfer capability,extra-large surface area and easily functionalized ability,the graphene-based nanocomposites have been employed to fabricate electrochemical biosensors including immunosensors and aptasensors for detecting microbial toxins with high sensitivity.The specificity and selectivity of the electrochemical biosensors for targeting toxins can be achieved by combining graphene nanocomposites with antibodies and/or aptamers.The graphene nanocompositebased electrochemical biosensors could become a promising technique in the detection of microbial toxins for public and environmental health protection.展开更多
A friendly biomimetic process was adopted for the mild preparation of"all-inclusive"organic-inorganic nanospheres,which effectively integrate biorecognition function and signal amplification function.The res...A friendly biomimetic process was adopted for the mild preparation of"all-inclusive"organic-inorganic nanospheres,which effectively integrate biorecognition function and signal amplification function.The resulted Ca3(PO4)2-Ab2-BSA nanospheres were employed as signal labels for enhancing detection of nuclear matrix protein 22(NMP 22).The fabricated electrochemical immunosensor exhibited a linear range(0.08-77.00 U/mL)and an ultralow limit of detection(0.01 U/mL)towards NMP 22,which can be taken as a promising tool for clinical diagnosis of bladder cancer.展开更多
An electrochemical immunosensor for sensitive detection of thyroid stimulating hormone(TSH) has been developed by using an inkjet printed microchip and based on a double signal amplification strategy using magnetic be...An electrochemical immunosensor for sensitive detection of thyroid stimulating hormone(TSH) has been developed by using an inkjet printed microchip and based on a double signal amplification strategy using magnetic beads(MBs), alkaline phosphatase(ALP) and p-aminophenyl phosphate(pAPP) reaction.Differential pulse voltammetry(DPV), cyclic voltammogram(CV) and amperometric i-t curve(i-t) were employed to characterize the immunosensor. High sensitivity and good selectivity were observed. The detection linear range was from 0.01 μIU/mL to 10 μIU/mL, in which the peak currents increased along with the concentration. The detection limit was 0.005 μIU/mL at S/N = 3. The immunosensor was also applied for TSH detection in human serum with recoveries from 98.0% to 101.8% and relative standard deviations from 1.3% to 3.1%, demonstrating potential value in clinical diagnosis.展开更多
基金This work was financially supported by Major Science and Technology Project of Yunnan Province(202302AE090022)Key Research and Development Program of Yunnan(202203AC100010)+4 种基金the National Natural Science Foundation of China(32160597,32160236,32371463)National Key Research and Development Program of China(2022YFC2601604)Cardiovascular Ultrasound Innovation Team of Yunnan Province(202305AS350021)Spring City Plan:the High-level Talent Promotion and Training Project of Kunming(2022SCP001)the second phase of“Double-First Class”Program Construction of Yunnan University.
文摘Sensitive detection of Staphylococcus aureus enterotoxin B(SEB)is of importance for preventing food poisoning from threatening human health.In this work,an electrochemical and colorimetric dual-signal detection assay of SEB was developed.The probe(Ab2/AuPt@Fe-N-C)was bound to SEB captured by Ab1,where the Ab2/AuPt@Fe-N-C triggered methylene blue degradation and resulted in the decrease of electrochemical signal.Furthermore,the probe catalyzed the oxidation of 3,3’,5,5’-tetramethyl biphenyl to generate a colorimetric absorbance at 652 nm.Once the target was captured and formed a sandwich-like complex,the color changed from colorless to blue.SEB detection by colorimetric and electrochemical methods showed a linear relationship in the concentration ranges of 0.0002-10.0000 and 0.0005-10.0000 ng/mL,with limits of detection of 0.0667 and 0.1670 pg/mL,respectively.The dual-signal biosensor was successfully used to detect SEB in milk and water samples,which has great potential in toxin detection in food and the environment.
文摘The electrochemical immunosensor for a-fetoprotein (AFP) was fabricated based on the platform of gold nanoparticles (GNP)/graphene (Gr)-prussian blue (PB). By electrodeposition, GNP were modified on the surface of the prepared Gr-PB. The anti-AFP-1, l'-ferrocenedicarboxylic acid (FcDA) as label was directly immobilized on the platform of GNP/Gr-PB. And after the immunoreactions, the formed complex inhibited the electron transfer and decreased the catalytic current of FcDA toward the reduction of H2O2. And in the range of 10-3200 pgomL^-1, the decreased current is linear with the concentration of AFP, with a detection limit of 3 pg.mL-1. The developed im- munoassay method showed good precision, high sensitivity, acceptable stability and reproducibility, and could be used for the detection of real samples with consistent results in comparison with those obtained by the enzyme linked immunosorbent assay (ELISA) method.
基金financial supports of the National Natural Science Foundation of China(Nos.61471168,61571187)China Postdoctoral Science Foundation(No.2016T90403)+2 种基金Postdoctoral Science Foundation of Jiangsu Province(No.1601021A)the Natural Science Foundation of Hunan Province(No.2017JJ209)Hunan Key Research Project(No.2017SK2174)
文摘A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles(PTh-Au) modified glassy carbon electrode(GCE) as a platform and secondary antibody labeled Au NPs(Ab;-Au) as immumoprobe for carcinoembryonic antigen(CEA) detection. The sandwich-type biosensor adopted anodic stripping voltammetry to detect silver stripping signal when the Ab;-Au of the formed immunocomplexes were stained with silver. The optimized detection conditions were investigated. The effect of different electrochemical responses at various concentrations of CEA was checked by anodic stripping voltammetry. This immunosensor showed a low detection limit of 0.055 ng/mL and a wide linear calibration of 0.1-120 ng/mL(R;=0.99856). Moreover, this immunoassay also existed the advantages of good reproducibility, stability and selectivity. Thus, this immunosensing protocol may provide a potential application for effective clinical detection of CEA.
基金financially supported mainly by the Vietnam National Foundation for Science and Technology Development(No.103.99-2012.15)supported by VAST(VAST03.06/14-15 and VAST.DLT.04/14-15)
文摘In this study, a novel layer-by-layer polyaniline/graphene (PANi/Gr) structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition (CVD) method and transferred onto the PANi-predeposited microelectrode. The properties of PANi/Gr film were thoroughly investigated by high-resolution transmission electron microscopy and Raman techniques. The most attractive feature of this system is a suitable microenvironment, which could provide an amplifi- cation of the conductive signal, thus may contribute to enhancing electron transfer and subsequently improve the sensitivity in electrochemical measurements. With low detection limit (- 43 × 10 -12 g/L), ac-ceptable stability and good reproducibility, the proposed electrochemical immunosensor could be advantageously extended for multiplexed detection of other agents of environmental pollution.
基金funded by by National Key Research and Development Program of China(2021YFD1800403)National Natural Science Foundation of China(21475116,21575125 and 81302016)+4 种基金Natural Science Foundation of Jiangsu Province(BK20221370,BK20221281)Key University Natural Science Foundation of Jiangsu Province(20KJA150004)the Project for Science and Technology of Yangzhou(YZ2022074,YZ2020076)Crosscooperation project of Subei Peoples’Hospital of Jiangsu Province(SBJC220009)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_3203)
文摘Interferon-γis a kind of protein with a wide range of biological activities,which can regulate the immune function of the body,and can be used as an important marker to detect and treat bovine tuberculosis diseases.Here,a picogram-level bovine interferon-γ(BoIFN-γ)electrochemical impedance immunosensor was constructed for the first time using mesoporous silica nanospheres(MS Ns)to immobilize specific monoclonal BoIFN-y antibodies.The MS Ns and BoIFN-γimmuno sensors were characterized using scanning electron microscopy,transmission electron microscope,nitrogen adsorption experiment,X-ray photoelectron spectra,and contact angle measurements.MSNs possess a substantial specific surface area and significant hydrophilicity,and can immobilize many antibody molecules,thereby improving detection sensitivity.The immunosensor has a linear detection range from 0.001 to 10.0 ng/mL with an exceptionally low detection limit of 0.62 pg/mL.Compared to the traditional BoIFN-γanalysis method,BoIFN-γimmunosensor presents superiorities in sensitivity,wide linear range as well as short processing time.More importantly,the BoIFN-γsensor exhibits high selectivity,reliable repeatability as well as stability,providing a promising application prospect for the early diagnosis of Mycobacterium bovis infection.
文摘It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety.Taking the advantages of ultrahigh electron-transfer capability,extra-large surface area and easily functionalized ability,the graphene-based nanocomposites have been employed to fabricate electrochemical biosensors including immunosensors and aptasensors for detecting microbial toxins with high sensitivity.The specificity and selectivity of the electrochemical biosensors for targeting toxins can be achieved by combining graphene nanocomposites with antibodies and/or aptamers.The graphene nanocompositebased electrochemical biosensors could become a promising technique in the detection of microbial toxins for public and environmental health protection.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2017MB017)support from the One-Thousand-Talents Scheme in Sichuan Province。
文摘A friendly biomimetic process was adopted for the mild preparation of"all-inclusive"organic-inorganic nanospheres,which effectively integrate biorecognition function and signal amplification function.The resulted Ca3(PO4)2-Ab2-BSA nanospheres were employed as signal labels for enhancing detection of nuclear matrix protein 22(NMP 22).The fabricated electrochemical immunosensor exhibited a linear range(0.08-77.00 U/mL)and an ultralow limit of detection(0.01 U/mL)towards NMP 22,which can be taken as a promising tool for clinical diagnosis of bladder cancer.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.21775028,21375022)Scienceand Technology Commission of Shanghai Municipality(Nos.16391903900,17JC1401900,17JC1400200)
文摘An electrochemical immunosensor for sensitive detection of thyroid stimulating hormone(TSH) has been developed by using an inkjet printed microchip and based on a double signal amplification strategy using magnetic beads(MBs), alkaline phosphatase(ALP) and p-aminophenyl phosphate(pAPP) reaction.Differential pulse voltammetry(DPV), cyclic voltammogram(CV) and amperometric i-t curve(i-t) were employed to characterize the immunosensor. High sensitivity and good selectivity were observed. The detection linear range was from 0.01 μIU/mL to 10 μIU/mL, in which the peak currents increased along with the concentration. The detection limit was 0.005 μIU/mL at S/N = 3. The immunosensor was also applied for TSH detection in human serum with recoveries from 98.0% to 101.8% and relative standard deviations from 1.3% to 3.1%, demonstrating potential value in clinical diagnosis.