Polymerase chain reaction (PCR) is a useful technique for in vitro amplification of a DNA fragment. In this paper, a PCR procedure using Au nanoparticle (AuNP) -bound primers was systemically studied. The 5′-SH- (CH2...Polymerase chain reaction (PCR) is a useful technique for in vitro amplification of a DNA fragment. In this paper, a PCR procedure using Au nanoparticle (AuNP) -bound primers was systemically studied. The 5′-SH- (CH2)6-modified primers were covalently attached to the AuNP surface via Au-S bonds, and plasmid pBluescript SK was used as a template. The effects of the concentration of AuNP-bound primers, annealing temperature and PCR cy-cles were evaluated, respectively. The results indicate that PCR can proceed successfully under optimized condition, with either forward or reverse primers bound to the AuNP surface or with both the two primers bound to the AuNP surface. Development of PCR procedure based on AuNPs not only makes the isolation of PCR products very convenient, but also provides novel methods to prepare AuNP-bound ssDNA and nanostructured material.展开更多
A novel multilayer film based on Au nanoparticles(AuNPs) and polyaniline/carboxylated multiwall carbon nanotubes-chitosan nanocomposite(PANI/MWCNTs/CS) was exploited to fabricate a highly sensitive immunosensor for de...A novel multilayer film based on Au nanoparticles(AuNPs) and polyaniline/carboxylated multiwall carbon nanotubes-chitosan nanocomposite(PANI/MWCNTs/CS) was exploited to fabricate a highly sensitive immunosensor for detecting chlorpyrifos. PANI-coated MWCNTs were prepared by in situ chemical polymerization and carboxylated MWCNTs played an important role in obtaining the thin and uniform coating of PANI resulting in the improved immunosensor response. Au NPs were used as a linker to immobilize chlorpyrifos antibody. The performance of the immunosensor was characterized by means of cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM), respectively. All variables involved in the preparation process and analytical performance of the immunosensor were optimized.Under optimal conditions(antibody concentration: 5 μg/mL, working buffer pH: 6.5, incubation time: 40 min,incubation temperature: 25℃), the immunosensor exhibited a wide linear range from 0.1 to 40× 10^(-6)mg/mL and from 40 × 10^(-6)mg/mL to 500 × 10^(-6)mg/mL, and with a detection limit of 0.06 × 10^(-6)mg/mL, which provided a valuable tool for the chlorpyrifos detection in real samples.展开更多
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
Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme.Despite tremendous endeavor has been devoted to using gold nanoparticles(AuNPs)...Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme.Despite tremendous endeavor has been devoted to using gold nanoparticles(AuNPs)as conjugation matrix due to its fascinating physico-chemical properties,maintaining enzymatic activity while circumventing cumbersome modification remains a formidable challenge.Herein,the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent.As the proof of concept,glucose oxidase(GOx)was chosen as model enzyme.The one-pot conjugation process can be facilely completed at−20°C under aqueous solution.Moreover,with the loading of GOx on AuNP at freezing,the enzyme exhibited superior catalytic activity and stability upon thermal and pH perturbation.The mechanism of boosted activity was then discussed in detail.It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity.More importantly,this methodology was universal and can also be applied to other enzyme which contains natural cysteine,such as horseradish peroxidase(HRP)and papain.This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing,microdevice and even drug delivery.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.20443005)the Nanotechnology Special Projects of Shanghai(Grant No.0352nm123)the Major Project Foundation of Shanghai Education Administration(Grant No.04DA01).
文摘Polymerase chain reaction (PCR) is a useful technique for in vitro amplification of a DNA fragment. In this paper, a PCR procedure using Au nanoparticle (AuNP) -bound primers was systemically studied. The 5′-SH- (CH2)6-modified primers were covalently attached to the AuNP surface via Au-S bonds, and plasmid pBluescript SK was used as a template. The effects of the concentration of AuNP-bound primers, annealing temperature and PCR cy-cles were evaluated, respectively. The results indicate that PCR can proceed successfully under optimized condition, with either forward or reverse primers bound to the AuNP surface or with both the two primers bound to the AuNP surface. Development of PCR procedure based on AuNPs not only makes the isolation of PCR products very convenient, but also provides novel methods to prepare AuNP-bound ssDNA and nanostructured material.
基金supported by the National Natural Science Foundation of China (No. 30972055, 31101286)Agricultural Science and Technology Achievements Transformation Fund Projects of the Ministry of Science and Technology of China (No. 2011GB2C60020)Shandong Provincial Natural Science Foundation, China (No. Q2008D03)
文摘A novel multilayer film based on Au nanoparticles(AuNPs) and polyaniline/carboxylated multiwall carbon nanotubes-chitosan nanocomposite(PANI/MWCNTs/CS) was exploited to fabricate a highly sensitive immunosensor for detecting chlorpyrifos. PANI-coated MWCNTs were prepared by in situ chemical polymerization and carboxylated MWCNTs played an important role in obtaining the thin and uniform coating of PANI resulting in the improved immunosensor response. Au NPs were used as a linker to immobilize chlorpyrifos antibody. The performance of the immunosensor was characterized by means of cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM), respectively. All variables involved in the preparation process and analytical performance of the immunosensor were optimized.Under optimal conditions(antibody concentration: 5 μg/mL, working buffer pH: 6.5, incubation time: 40 min,incubation temperature: 25℃), the immunosensor exhibited a wide linear range from 0.1 to 40× 10^(-6)mg/mL and from 40 × 10^(-6)mg/mL to 500 × 10^(-6)mg/mL, and with a detection limit of 0.06 × 10^(-6)mg/mL, which provided a valuable tool for the chlorpyrifos detection in real samples.
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the National Natural Science Foundation of China(Nos.32001782 and 22222402)the Natural Science Foundation of Hunan Province(No.2021JJ40564)+2 种基金Changsha Municipal Natural Science Foundation(No.kq2007021)the Opening Foundation of State Key Laboratory of Chemo/Biosensing and Chemometrics,Hunan University(No.2019013)Open Project of State Key Laboratory of Supramolecular Structure and Materials(No.sklssm2023016).
文摘Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme.Despite tremendous endeavor has been devoted to using gold nanoparticles(AuNPs)as conjugation matrix due to its fascinating physico-chemical properties,maintaining enzymatic activity while circumventing cumbersome modification remains a formidable challenge.Herein,the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent.As the proof of concept,glucose oxidase(GOx)was chosen as model enzyme.The one-pot conjugation process can be facilely completed at−20°C under aqueous solution.Moreover,with the loading of GOx on AuNP at freezing,the enzyme exhibited superior catalytic activity and stability upon thermal and pH perturbation.The mechanism of boosted activity was then discussed in detail.It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity.More importantly,this methodology was universal and can also be applied to other enzyme which contains natural cysteine,such as horseradish peroxidase(HRP)and papain.This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing,microdevice and even drug delivery.
