Sensitive monitoring of the target products during the biosynthesis process is crucial,and facile analytical approaches are urgently needed.Herein,phosphatidylserine(PS)was chosen as the model target,a colorimetric ap...Sensitive monitoring of the target products during the biosynthesis process is crucial,and facile analytical approaches are urgently needed.Herein,phosphatidylserine(PS)was chosen as the model target,a colorimetric aptasensor was developed for the rapid quantitation in biosynthesis samples.A chimeric aptamer was constructed with two homogeneous original PS aptamers.Specific recognition between the chimeric aptamer and PS results in the desorption of aptamer from the surface of the AuNPs nanozyme,and the peroxidase-like enzymatic activity of the AuNPs nanozyme was weakened in a relationship with the different concentrations.The developed aptasensor performed well when applied for analyzing PS in biosynthesis samples.The aptasensor offers good sensitivity and selectivity,under optimal conditions,achieving monitoring and quantitation of PS in the range of 2.5-80.0μmol/L,with a limit of detection at 536.2 nmol/L.Moreover,the aptasensor provides good accuracy,with comparison rates of 98.17%-106.40%,when compared with the HPLC-ELSD.This study provides a good reference for monitoring other biosynthesized products and promoting the development of aptamers and aptasensors in real-world applications.展开更多
Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a n...Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a necessity.We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu^(2+)by exploiting the electroanalytical technique of square wave voltammetry.We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam,which is then electrochemically seeded with gold nanoparticles(Au NPs).The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O.As a result,the heavy metals Pb2+(0.020 mg.L^(-1)detection limit;2.0–16.0 mg.L^(-1)detection range)and Cu^(2+)(0.013 mg.L^(-1)detection limit;0.4–12.8 mg.L^(-1)detection range)can be detected simultaneously with high precision.Furthermore,other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode’s performance,and the recovery rate of groundwater samples varied between 96.3%±2.1%and 109.4%±0.6%.The compactness,flexible shape,low power consumption,and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater,thereby demonstrating the potential to revolutionize the field of environmental monitoring.展开更多
Inosine monophosphate(IMP),as a critical umami substance,is one of the most important indicators for evaluating the quality of meat products.Here,a sensitive electrochemiluminescence(ECL)biosensor based on graphdiyne(...Inosine monophosphate(IMP),as a critical umami substance,is one of the most important indicators for evaluating the quality of meat products.Here,a sensitive electrochemiluminescence(ECL)biosensor based on graphdiyne(GDY)/AuNPs/luminol nanocomposites was constructed to detect IMP.The GDY/AuNPs/luminol nanocomposites were synthesized by using simple one-pot method.GDY utilized its 2D framework to disperse and fix gold nanoparticles,which inhibited the agglomeration of gold nanoparticles and greatly improved its stability and catalytic properties.Importantly,GDY/AuNPs/luminol nanocomposites showed excellent catalytic ability and superior ECL activity towards luminol-H_(2)O_(2) systems due to the synergistic effect of GDY and AuNPs.Under optimal conditions,the prepared biosensor exhibited a wide linear range from 0.01 g/L to 20 g/L,a satisfactory limit detection of 0.0013 g/L,as well as an excellent specificity.Moreover,we carried out the precise analysis of IMP in actual meat samples with acceptable results compared to the liquid chromatography.We believe that this work could offer an efficient ECL platform for accurate and reliable report of IMP levels,which is significant for maintaining food quality and safety.展开更多
Gold nanoparticles-dimethylsiloxane(AuNPs-PDMS) membrane is a novel composite material in biochemical technology an d micro-electro-mechanical system(MEMS) research.It is widely used in biomed ici ne,biochemical detec...Gold nanoparticles-dimethylsiloxane(AuNPs-PDMS) membrane is a novel composite material in biochemical technology an d micro-electro-mechanical system(MEMS) research.It is widely used in biomed ici ne,biochemical detection and en vironmental protection due to its biocompatibility,elasticity and electric char acteristics.In this paper,the characteristics of the composite membrane were d escribed,and four methods for fabricating AuNPs-PDMS composite membranes were reviewed in detail.Besides,the advantages and disadvantages of the four method s were summarized,and the present problems and future researches were proposed.展开更多
DNA methylation plays a significant role in various biological events, and its precise determination is vital for the prognosis and treatment of cancer. Here, we proposed an ultrasensitive electrochemical biosensor fo...DNA methylation plays a significant role in various biological events, and its precise determination is vital for the prognosis and treatment of cancer. Here, we proposed an ultrasensitive electrochemical biosensor for the quantitative analysis of multiple methylation-locus in DNA sequence via DNA anchoring the gold nanoparticles (DNA-AuNPs) and bienzyme dual signal amplifications. After the target DNA captured by the DNA-AuNPs of the biosensor, the methyl-CpG binding protein MeCP2 could specifically conjugate to the methylation-loci in the double-stranded DNA. Successively, the glucose oxidase (GOD) and horseradish (HRP) co-labeled antibody captured the His tagged MeCP2, which leads to a cascade enzymatic catalysis of the substrates to yield a detectable electrochemical signal. Both the two strategies, including the high content of DNA-AuNPs and the associated catalysis of bienzyme, dramatically enhanced the sensitivity of the biosensor. The response current elevated with the increasing numbers of methylation-locus, thus the multiple methylated DNA was identified by detecting the corresponding current signals. This method could detect the methylated target as low as 0.1 fM, and showed a wide linear range from 10 - 15 M to 10 - 7 M. Besides, the long-term stability and repeatability of the biosensor were also validated. The prepared electrochemical immunosensor exhibits ultrasensitivity through the bienzyme labeling process, which can be applied for the detection of DNA methylation with low concentration.展开更多
基金supported by the National Natural Science Foundation of China(31922072)the Natural Science Foundation of Shandong Province(ZR2020JQ15)the Taishan Scholar Project of Shandong Province(tsqn201812020)。
文摘Sensitive monitoring of the target products during the biosynthesis process is crucial,and facile analytical approaches are urgently needed.Herein,phosphatidylserine(PS)was chosen as the model target,a colorimetric aptasensor was developed for the rapid quantitation in biosynthesis samples.A chimeric aptamer was constructed with two homogeneous original PS aptamers.Specific recognition between the chimeric aptamer and PS results in the desorption of aptamer from the surface of the AuNPs nanozyme,and the peroxidase-like enzymatic activity of the AuNPs nanozyme was weakened in a relationship with the different concentrations.The developed aptasensor performed well when applied for analyzing PS in biosynthesis samples.The aptasensor offers good sensitivity and selectivity,under optimal conditions,achieving monitoring and quantitation of PS in the range of 2.5-80.0μmol/L,with a limit of detection at 536.2 nmol/L.Moreover,the aptasensor provides good accuracy,with comparison rates of 98.17%-106.40%,when compared with the HPLC-ELSD.This study provides a good reference for monitoring other biosynthesized products and promoting the development of aptamers and aptasensors in real-world applications.
基金supported by the National Key Research and Development Project of China(2019YFC1804802)。
文摘Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a necessity.We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu^(2+)by exploiting the electroanalytical technique of square wave voltammetry.We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam,which is then electrochemically seeded with gold nanoparticles(Au NPs).The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O.As a result,the heavy metals Pb2+(0.020 mg.L^(-1)detection limit;2.0–16.0 mg.L^(-1)detection range)and Cu^(2+)(0.013 mg.L^(-1)detection limit;0.4–12.8 mg.L^(-1)detection range)can be detected simultaneously with high precision.Furthermore,other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode’s performance,and the recovery rate of groundwater samples varied between 96.3%±2.1%and 109.4%±0.6%.The compactness,flexible shape,low power consumption,and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater,thereby demonstrating the potential to revolutionize the field of environmental monitoring.
基金supported by The National Natural Science Foundation of China(31972198,31622042)The National Key R&D Program of China(2016YFD0400803,2016YFD0401501).
文摘Inosine monophosphate(IMP),as a critical umami substance,is one of the most important indicators for evaluating the quality of meat products.Here,a sensitive electrochemiluminescence(ECL)biosensor based on graphdiyne(GDY)/AuNPs/luminol nanocomposites was constructed to detect IMP.The GDY/AuNPs/luminol nanocomposites were synthesized by using simple one-pot method.GDY utilized its 2D framework to disperse and fix gold nanoparticles,which inhibited the agglomeration of gold nanoparticles and greatly improved its stability and catalytic properties.Importantly,GDY/AuNPs/luminol nanocomposites showed excellent catalytic ability and superior ECL activity towards luminol-H_(2)O_(2) systems due to the synergistic effect of GDY and AuNPs.Under optimal conditions,the prepared biosensor exhibited a wide linear range from 0.01 g/L to 20 g/L,a satisfactory limit detection of 0.0013 g/L,as well as an excellent specificity.Moreover,we carried out the precise analysis of IMP in actual meat samples with acceptable results compared to the liquid chromatography.We believe that this work could offer an efficient ECL platform for accurate and reliable report of IMP levels,which is significant for maintaining food quality and safety.
基金National Natural Science Foundation of China (No.51105267, No.91123036)China Postdoctoral Science Foundation(No.2011M500542, No.2012T50248)+1 种基金National Research Foundation for the Doctoral Program of Higher Education of China (No.20111402120007)Shanxi Provincial Foundation for Returned Scholars (No.2011x10)
文摘Gold nanoparticles-dimethylsiloxane(AuNPs-PDMS) membrane is a novel composite material in biochemical technology an d micro-electro-mechanical system(MEMS) research.It is widely used in biomed ici ne,biochemical detection and en vironmental protection due to its biocompatibility,elasticity and electric char acteristics.In this paper,the characteristics of the composite membrane were d escribed,and four methods for fabricating AuNPs-PDMS composite membranes were reviewed in detail.Besides,the advantages and disadvantages of the four method s were summarized,and the present problems and future researches were proposed.
文摘DNA methylation plays a significant role in various biological events, and its precise determination is vital for the prognosis and treatment of cancer. Here, we proposed an ultrasensitive electrochemical biosensor for the quantitative analysis of multiple methylation-locus in DNA sequence via DNA anchoring the gold nanoparticles (DNA-AuNPs) and bienzyme dual signal amplifications. After the target DNA captured by the DNA-AuNPs of the biosensor, the methyl-CpG binding protein MeCP2 could specifically conjugate to the methylation-loci in the double-stranded DNA. Successively, the glucose oxidase (GOD) and horseradish (HRP) co-labeled antibody captured the His tagged MeCP2, which leads to a cascade enzymatic catalysis of the substrates to yield a detectable electrochemical signal. Both the two strategies, including the high content of DNA-AuNPs and the associated catalysis of bienzyme, dramatically enhanced the sensitivity of the biosensor. The response current elevated with the increasing numbers of methylation-locus, thus the multiple methylated DNA was identified by detecting the corresponding current signals. This method could detect the methylated target as low as 0.1 fM, and showed a wide linear range from 10 - 15 M to 10 - 7 M. Besides, the long-term stability and repeatability of the biosensor were also validated. The prepared electrochemical immunosensor exhibits ultrasensitivity through the bienzyme labeling process, which can be applied for the detection of DNA methylation with low concentration.
