ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2015
·Vol. 408
·期 4
·1015-1022
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IF 3.436
Wang Shasha,Chen Zhaopeng,Choo Jaebum,Chen Lingxin
A naked-eye sensitive ELISA-like assay was developed based on gold-enhanced peroxidase-like activity of gold nanoparticles (AuNPs). Using human IgG (H-IgG) as an analytical model, goat anti-human IgG antibody (anti-IgG) adsorbed on microtiter plate and AuNPs-labeled anti-IgG acted as capture antibody and detection antibody, respectively. Because the surfaces of AuNPs were blocked by protein molecules, the peroxidase-like activity of AuNPs was almost inhibited, evaluated by the catalytic oxidation of peroxidase enzyme substrate 3,3′,5,5′-tetramethylbenzidine (TMB), which could produce a bright blue color in the presence of H 2 O 2 . Fortunately, the catalytic ability of AuNPs was dramatically increased by the deposition of gold due to the formation of a new gold shell on immunogold. Under optimal reaction conditions, the colorimetric immunoassay presented a good linear relationship in the range of 0.7–100 ng/mL and the limit of detection (LOD) of 0.3 ng/mL calculated by 3σ/S for UV-vis detection, and obtained LOD of 5 ng/mL for naked-eye detection. The obtained results were competitive with conventional sandwich ELISA with the LOD of 1.6 ng/mL. Furthermore, this developed colorimetric immunoassay was successfully applied to diluted human serum and fetal bovine serum samples, and predicted a broad prospect for the use of peroxidase-like activity involving nanomaterials in bioassay and diagnostics.
A naked-eye ELISA-like immunoassay for determination of human IgG is described based on gold enhanced peroxidase like activity of gold nanoparticles and it is a colorimetric typical sandwich-type immunoassay format with high sensitivity
研究领域:
分析化学
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生物医学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
·
IF 4.758
Ling Zou,Yulan Tian,Xi Zhang,Jiaru Fang,Ning Hu,Ping Wang
This work describes an immunosensor for the determination of okadaic acid (OA) using a Love-wave sensor with the immunogold staining method. In this assay, OA-BSA was captured by the anti-BSA antibody (BSA-MAb) bond with staphylococcal protein A (SPA) on the sensor surface via Fc regions. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were employed to monitor the fabrication steps of immunosensor using the redox probe of K 3 Fe(CN) 6 . An indirect competitive immunoassay format was employed to detect OA after the immunosensor was prepared and gold nanoparticles (AuNPs) were introduced to amplify the phase signal. The results demonstrated that developed immunosensor was able to specifically respond to OA ranging from 10 to 150 ng/mL, providing limit of detection of 5.5 ng/mL. When applied to determine OA concentration in real sample, the results agreed well with those obtained by the commercial ELISA assay. The developed immunosensor is therefore suitable and has great application potential in detection of OA in shellfish.
研究领域:
分析化学
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食品安全
·
生物传感器
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产品关联
DOI
高影响因子
Biosensors-Basel
·
2024
·Vol. 15
·期 1
·10
·
IF 4.9
Yutong Wu,Yang Liu,Jinchen Ma,Shanxi Zhu,Xiaojun Zhao,Huawei Mou,Xuanqi Ke,Zhisheng Wu,Yifei Wang,Sheng Lin,Wuzhen Qi
Microbial contamination is an important factor threatening the safety of Chinese medicine preparations, and microfluidic detection methods have demonstrated excellent advantages in the application of rapid bacterial detection. In our study, a novel optical biosensor was developed for the rapid and sensitive detection of Salmonella in traditional Chinese medicine on a microfluidic chip. Immune gold@platinum nanocatalysts (Au@PtNCs) were utilized for specific bacterial labeling, while magnetic nano-beads (MNBs) with a novel high-gradient magnetic field were employed for the specific capture of bacteria. The immune MNBs, immune Au@PtNCs, and bacterial samples were introduced into a novel passive microfluidic micromixer for full mixing, resulting in the formation of a double-antibody sandwich structure due to antigen–antibody immune reactions. Subsequently, the mixture flowed into the reaction cell, where the MNBs- Salmonella -Au@PtNCs complex was captured by the magnetic field. After washing, hydrogen peroxide-tetramethylbenzidine substrate (H 2 O 2 -TMB) was added, reacting with the Au@PtNCs peroxidase to produce a blue reaction product. This entire process was automated using a portable device, and Salmonella concentration was analyzed via a phone application. This simple biosensor has good specificity with a detection range of 9 × 10 1 –9 × 10 5 CFU/mL and can detect Salmonella concentrations as low as 90 CFU/mL within 74 min. The average recoveries of the spiked samples ranged from 76.8% to 109.5%
研究领域:
微生物学
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药物分析
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生物传感技术
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2010
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IF 2.6
Chunyuan Song,Zhuyuan Wang,Jing Yang,Ruohu Zhang,Yiping Cui
A detailed method for preparation of 2-mercaptobenzothiazole (MBT)-labeled immuno-Au aggregates as a novel Raman probe for SERS-based immunoassay has been proposed in this paper. The formation kinetics of gold aggregates induced by MBT and the impact of the amount of labeled reporter on the aggregation, as well as the fabrication of MBT-labeled immuno-Au aggregates were characterized comprehensively by UV–vis spectrophotometer . Meanwhile, a chain-like morphology of aggregates was monitored by TEM images. Experimental results show that this Raman tag can act as an efficient label and an enhanced Raman signal of SERS-based immunoassay can be obtained successfully with this novel probe. This work shows the method for the preparation of immune probe for SERS-based immunoassay using MBT as reporter and provides a reference for the preparation of immune probe with other Raman markers for multi-channel SERS-based immunoassay.
研究领域:
分析化学
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纳米技术
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生物传感器
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免疫分析
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2024
·
IF 8.5
Fan Jiang,Nana Jin,Lei Wang,Siyuan Wang,Yanbin Li,Jianhan Lin
Salmonella screening is essential to avoid food poisoning . A simple, fast and sensitive colorimetric biosensor was elaborately developed for Salmonella detection on a microfluidic chip through limiting air chambers for precise air control, switching rotary valves for accurate fluid selection, a convergence-and-divergence passive micromixer and an extrusion-and-suction active micromixer for efficient fluid mixing, and immune gold@platinum palladium nanocatalysts for effective signal amplification. The mixture of bacteria, immune magnetic nanobeads and nanocatalysts was first rapidly mixed to form nanobead-bacteria-nanocatalyst conjugates and magnetically separated for enrichment. After washing with water, the conjugates were used to catalyze colorless substrate and blue product was finally analyzed using ImageJ for quantifying bacterial concentration. The finger-actuated microfluidic chip enabled designated control of designated fluids in designated places towards designated directions by simple press-release operations on designated air chambers without any external power. Under optimal conditions, this sensor could detect Salmonella at 45 CFU/mL in 25 min.
研究领域:
生物传感器
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微流控技术
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纳米技术
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食品安全
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分析化学
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DOI
PubMed
高影响因子
ACS Nano
·
2024
·
IF 15.8
Qian Cheng,Xiaolei Shi,Yuzhe Chen,Qilin Li,Jiawei Wang,Heli Li,Lin Wang,Zheng Wang
Abnormal tumor microenvironment (TME) imposes barriers to nanomedicine penetration into tumors and evolves tumor-supportive nature to provide tumor cell protection, seriously weakening the action of antitumor nanomedicines and posing significant challenges to their development. Here, we engineer a TME-activatable size-switchable core–satellite nanosystem (Mn-TI-Ag@HA) capable of increasing the effective dose of therapeutic agents in deep-seated tumors while reversing tumor-supportive microenvironment for augmenting immuno/metal-ion therapy. When activated by TME, the nanosystem disintegrates, allowing ultrasmall-sized Ag nanoparticles to become unbound and penetrate deep into solid tumors. Simultaneously, the nanosystem produces O2 and releases TGF-β inhibitors in situ to drive macrophage M2-to-M1 polarization, increasing intratumoral H2O2 concentration, and ultimately augmenting metal-ion therapy by accelerating hypertoxic Ag+ production. The nanosystem can overcome multiple obstacles that aid in tumor resistance to nanomedicine, demonstrating effective tumor penetration, TME regulation, and tumor inhibition effects. It can provoke long-term immunological memory effects against tumor rechallenge when combined with immune checkpoint inhibitor anti-PD-1. This work provides a paradigm for designing efficient antitumor nanomedicines.
研究领域:
纳米技术
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癌症生物学
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免疫疗法
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药物递送系统
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肿瘤微环境
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产品关联
DOI
PubMed
高影响因子
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