FOOD CHEMISTRY
·
2021
·
IF 7.514
Shuyun Bi,Di Shao,Yue Yuan,Rui Zhao,Xu Li
A novel surface-enhanced Raman spectroscopy (SERS) method for the determination of nitrofurazone was developed using AuNPs/ γ -Al 2 O 3 nanoparticles protected by β -cyclodextrin ( β -CD) as substrate prepared in our lab. The optimum experimental conditions were obtained from single factor procedure and response surface modeling. A linear relationship ( I SERS = 508.96 c + 31987.87, c : nmol L −1 , R 2 = 0.996) between SERS intensity and the concentration of nitrofurazone in the range of 3.3 – 667.0 nmol L −1 was established, the limit of detection (LOD) was found at nmol L −1 level (0.37 nmol L −1 by 3 S 0 / S ). The selectivity for the method was studied by the influences of foreign substances on the determination. The recoveries and RSD (n = 5) for the six meat samples were 95.1 % – 104.5% and 2.4 % – 4.8% respectively, which suggesting that the new SERS method was successfully to detecting nitrofurazone.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOELECTROCHEMISTRY
·
2019
·
IF 4.474
Lingpu Jia,Yaxin Zhou,Kaipeng Wu,Qingling Feng,Chunming Wang,Ping He
A flexible acetylcholinesterase (AChE) film biosensor, based on a AuNPs-MoS 2 -reduced graphene oxide/polyimide flexible film (rGO/PI) electrode, has been synthesized for paraoxon detection. In this study, the rGO/PI film acts as the flexible substrate and AuNPs are reduced by monolayer MoS 2 under illumination. Transmission electron microscopy revealed that AuNPs are uniformly dispersed on the MoS 2 -rGO/PI electrode surface with a diameter ~10 nm. X-ray photoelectron spectroscopy indicated that a strong binding force exists between reduced AuNPs and monolayer MoS 2 . The AChE modified AuNPs-MoS 2 -rGO/PI flexible film biosensor is used to hydrolyze acetylcholine chloride and obtain a large current response at 0.49 V by differential pulse voltammetry , demonstrating successful immobilization of AChE. In view of the inhibition of paraoxon on the AChE, under optimal conditions, the AChE/AuNPs-MoS 2 -rGO/PI film biosensor shows a linear response over a concentration range 0.005–0.150 μg/mL, a sensitivity of 4.44 uA/μg/ mL, a detection limit of 0.0014 μg/mL, acceptable reproducibility and stability to paraoxon. The flexible film biosensor has also proved used for detection of paraoxon in real samples.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Express
·
2019
·Vol. 9
·期 5
·444-450
·
IF 1.465
Lai Yuxuan,Huang Hao,Xia Zhihuan,Li Song,Deng Yan,Liu Xueying
A sandwich-type electrochemical immunosensor was developed in this study for sensitive detection of carcinoembryonic antigen (CEA) based on rGO/CS/AuNPs as a sensing platform and PTh-Au composites as signal labels. Reduced graphene oxide (rGO), Chitosan (CS) and AuNPs were layer by
layer modified on glass carbon electrode (GCE), which effectively enhanced electron transfer and provided excellent large electrochemical active surface area. Polythionine-Au composites prepared by chemical reduction method greatly amplified electrochemical signal with high conductivity and
large surface area. The prepared immunosensor showed high sensitivity, good stability and selectivity for detection of CEA with a wide range of 0.3 ng/mL to 30 ng/mL (R
2 = 0.9972) and a detection limit as low as 0.1471 pg/mL. Furthermore, this sandwich-type immunosensor might
be as a versatile platform for reliable early cancer diagnostics clinical.
✓ 已验证
产品关联
DOI
高影响因子
Food Analytical Methods
·
2019
·Vol. 12
·期 10
·2161-2171
·
IF 2.413
Lai Xiaoxia,Yan Shang,Ye Nengsheng,Xiang Yuhong
Acetylcholinesterase (AChE) can catalyze the hydrolysis of acetylthiocholine iodide (S-ACh-I) to produce thiocholine, which can crosslink with gold nanoparticles (AuNPs) by Au-S covalent bond and trigger AuNPs aggregation. The catalytic ability of aggregation of AuNPs is less than dispersed AuNPs. In the presence of carbaryl, which can inhibit the catalysis activity of AChE, therefore, the production amounts of thiocholine and aggregation degree were decreased. In the Fehling reaction, low aggregation degree AuNPs was used to catalyze the reduction of Cu 2+ by glucose to form large size Cu 2 O particle. Large Cu 2 O particle has high resonance scattering signal intensities, which is negative correlated with carbaryl concentration. The developed assay was applied to detect the carbaryl in aqueous solutions, and two excellent linear relationships were obtained in the range of 0.03–3.31 nM and 26.50–265.05 nM. The limit of detection (LOD) of carbaryl was down to 17.49 pM. The proposed method was successfully used to determine the concentration of spiked carbaryl in the apple matrix, and satisfactory recovery and repeatability were obtained.
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2019
·
IF 5.399
Yang-Yang Wu,Pengcheng Huang,Fang-Ying Wu
We devise a novel colorimetric aptasensor for multiplex antibiotics based on an ss-DNA fragment coordinately controlling gold nanoparticles (AuNPs) aggregation. The multifunctional aptamer (Apt) was elaborately designed to be adsorbed on AuNPs surfaces acting as a binding element for antibiotics and a molecular switch. Chloramphenicol (CAP) and tetracycline (TET) were selected as the model antibiotics. When one kind of antibiotics was added, the specifically recognized fragment of Apt can bind to it and dissociated, and the non-specific one coordinately controls AuNPs aggregation under high-salt conditions. Hence, different color changes of AuNPs solution can be used as the signal readout. The aptasensor exhibited remarkable selectivity and sensitivity for separate detection of TET and CAP, and the detection limits are estimated to be 32.9 and 7.0 nM, respectively. The analysis with the absorption spectroscopy and the smartphone are applied to detect antibiotics in real samples with consistent results and desirable recoveries.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2014
·
IF 6.451
Xiaoying Jing,Xianqing Cao,Li Wang,Tian Lan,Yiyan Li,Guoming Xie
A sensitive and selective electrochemical method was developed for the detection of DNA methylation , determination of DNA methyltransferase (MTase) activity and screening of MTase inhibitor. Methylene blue (MB) was employed as electrochemical indicator and DNA-modified gold nanoparticles (AuNPs) were used as signal amplification unit because the DNA strands in this composite have strong adsorption ability for MB. First, the thiolated single-stranded DNA S1 was self-assembled on gold electrode, hybridization between the lower portion of DNA S1 and its complementary DNA S2 formed an identical double-stranded tetranucleotide target sequence for both DNA adenine methylation (Dam) MTase and methylation-resistant endonuclease Mbo I, then the upper portion of DNA S1 was hybridized with its complementary DNA S3 modified on AuNPs to bring the DNA S3-AuNPs amplification units onto the electrode. The DNA S1/S2/S3-AuNPs bioconjugate has lots of DNA strands, and they can adsorb abundant MB. Mbo I endounuclease could not cleave the identical target sequence after it was methylated by Dam MTase. On the contrary, the sequence without methylation could be cleaved, which would decrease the amount of adsorbed MB. The presence of redox-active MB was detected electrochemically by differential pulse voltammetry (DPV). Thus, the activity of Dam MTase and methylation status were sensitively converted to the DNA S3-AuNPs amplified DPV signals. The DPV signal demonstrated a linear relationship with logarithm of Dam concentration ranging from 0.075 to 30 U/mL, achieving a detection limit of 0.02 U/mL ( S / N =3). Also, screening of Dam MTase inhibitor 5-fluorouracil was successfully investigated using this fabricated sensor.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2015
·
IF 4.513
Xiaozhe Xu,Juan Qiao,Nan Li,Li Qi,Shufeng Zhang
A new fluorescent probe based on ensemble of gold nanoclusters (AuNCs) and polymer protected gold nanoparticles (AuNPs) for turn-on sensing of l -cysteine was designed and prepared. The AuNCs were protected by bovine serum albumin and had strong fluorescence. The polymer protected AuNPs were synthesized by a facile in situ strategy at room temperature and could quench the fluorescence of AuNCs due to the Förster resonance energy transfer. Interestingly, it has been observed that the quenched fluorescence of AuNCs was recovered by l -cysteine, which could induce the aggregation of polymer protected AuNPs by sulfur group. Then the prepared fluorescent probe was successfully used for determination of l -Cys in human urines, which would have an evolving aspect and promote the subsequent exploration.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2024
·
IF 4.1
Jiaping Yang,Junpeng Deng,Yansheng Liu,Zhenle Qin,Jin Zhou,Xiaobo Jia,Guofu Wang,Yuqiang Weng,Feng Ling,Bin Zhou
Developing an efficient and sensitive method for detecting the coronavirus disease (COVID-19) is crucial. In this study, a phase-dependent SPR biosensor has been developed to detect the SARS-CoV-2 S protein with high sensitivity. The phase shifts of the SPR spectral interferogram are extracted using the windowed Fourier transform (WFT) method. The summation of the phase shifts of the prominent frequency, which make up the SPR spectral interferogram, is used as a numerical index to reflect the “negative” or “positive” results. The SARS-CoV-2 S protein antibody is modified onto an Au film, which serves as a sensing surface when detecting the SARS-CoV-2 S protein. The SARS-CoV-2 S protein antibody functionalized Au nanoparticles are used to form a (anti-S@AuNPs)-(SARS-CoV-2 S protein)-(Au film) sandwich structure, which reduces the SPR detection limitation to 1 ag/mL. An external laser is then used to induce the localized surface plasmon resonance (LSPR) between the AuNPs and the Au film in the sandwich structure, enhancing the detecting sensitivity by 357 %. This study provides a label-free method for detecting the SARS-CoV-2 S protein with low concentrations, indicating its potential in detecting the SARS-CoV-2 virus and viral disease diagnosis.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·
IF 2.7
Xiaojing Cui,Yaping Zhang,Hanmeng Zhang,Huaixia Yang,Yanju Liu,Fuchun Si
The sensitive detection of down-regulator of transcription 1 (DR1) plays an important role in the early diagnosis and treatment of Hashimoto's thyroiditis (HT). Herein, we report a novel electrochemical sensor based on the nanocomposite of tungsten oxide–gold nanoparticles (WO3@AuNPs) and hyperbranched polymer–2-bromo-isobutyryl bromide (HBP@BIBB) initiated atom transfer radical polymerization (ATRP) for the ultrasensitive assay of DR1. Monolayer WO3 nanosheets, which have high conductivity, were first compounded with AuNPs to obtain the WO3@AuNP nanocomposite. WO3@AuNPs can not only increase the conductivity of the electrode but also provide more active sites for biological molecules, thereby effectively amplifying the output signal. By introducing macroinitiator HBP@BIBB into the ATRP reaction, more electroactive molecules were introduced into the sensor, further amplifying the output signal and making the sensor ultra-sensitive. The optimized sensor demonstrated a wide linear range of 1 × 10−4 –1 × 102 ng mL−1 with a low detection limit of 2.91 fg mL−1. Moreover, the electrochemical biosensor has high selectivity, good stability, and strong anti-interference ability, and is suitable for the determination of DR1 in complex biological matrices. In conclusion, this electrochemical biosensor shows great potential in biomarker detection.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Xudong Li,Hongyan Zhang,Chu Chen,Haiyang Zhang,Chen Yang,Xiujuan Ma
A high-sensitivity NH 3 sensor based on gold nanoparticles or silver nanoparticles (AuNPs or AgNPs) modified ZnO (Au/ZnO or Ag/ZnO) was synthesized using hydrothermal method and the sensing mechanism was explained by density functional theory (DFT). Experimental results indicate that AuNPs or AgNPs modification can effectively improve the sensing characteristics of the ZnO-based NH 3 sensor, which is due to more hydroxyl groups, oxygen vacancies and oxygen free radicals on the surface of Au/ZnO or Ag/ZnO. The responses of AuZn2 and AgZn2 sensors to 1000 ppm NH 3 at room temperature are 7321.07 and 9329.79, which are 22.48 and 28.65 times higher than that of the ZnO sensor respectively. The low detection limits of the AuZn2 and AgZn2 sensors is 0.495 ppm and 0.405 ppm. The fast response/recovery times to 15 ppm NH 3 is 0.9 s / 0.9 s or 1.5 s / 0.9 s. DFT calculation results show that AuNPs or AgNPs on the ZnO surface make D-band center of ZnO moves to a higher energy level, which increases the chemical activity of AuZn2 or AgZn2, thereby improving the adsorption energy to NH 3 molecule. This work provides a new idea for high-performance NH 3 sensors fabrication and broadens the application field of ZnO materials.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Ting Zhang,Danni Ma,Fuman Cai
The accurate detection of glucose is critical for clinical diagnostics and metabolic monitoring. This study focused on the successful synthesis and incorporation of the glucose dehydrogenase (GDH) gene sequence from Burkholderia cepacia into a plasmid, followed by codon optimization and modification of cysteine motifs for increased expression in E. coli . The engineered E. coli strain demonstrated efficient heterologous expression of stable GDH. Remarkably, the recombinant strain not only enabled cost-effective GDH production but also exhibited excellent glucose catalytic activity, with a detection range of 1 μM to 10 mM and a minimum detectable concentration of 1 μM. This functionality makes it suitable for applications of AuNPs/SPE/glucose biosensors, offering high sensitivity for glucose detection—a novel achievement not previously reported. These findings have the potential to advance the clinical utilization of AuNPs/tetracysteine/GDH-modified biosensors and may promote the development of GDH-based electrochemical biosensors.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2025
·Vol. 55
·期 6
·1557-1569
·
IF 3
Zhang Xueni,Su Yuanzhang,Ao Debin,Hong Yan,Zou Min,Xie Jie,Zhou Qi,Wang Yuecong,He Wei,Chen Yuanming
A well-performing electrochemical immunosensor was prepared for detecting the tumor biomarker of carcinoembryonic antigen (CEA) by modifying a glassy carbon electrode (GCE) with a nanocomposite comprising gold nanoparticles (AuNPs), coiled carbon nanotubes (CCNTs), and chitosan (Chi) along with bovine serum proteins and CEA antibody. Various electrochemical methods such as cyclic voltammetry (CV) and square wave voltammetry (WV) were utilized for characterization. The substantial surface area and strong conductivity of AuNPs and CCNTs, and easy film-forming nature of Chi, enhanced the effective surface area and conductivity of the CEA-immunosensors to nearly twice that of the GCE before modification. Under the best experimental conditions, the CEA immunosensor showed good reproducibility with a selective linear detection range of 1 pg mL −1 –400 ng mL −1 and a detection limit as low as 1 pg mL −1 . The decrease in current exhibited a strong linear relationship with the logarithmic values of CEA concentration, boasting a correlation coefficient of 0.99379. The developed CEA immunosensor had good performance and the potential for practical application to real samples with good selectivity and immunity to other antigens in the presence of serum. Graphical abstract
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）