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About this sample
About this sample
Words: 1256 |
Pages: 3|
7 min read
Published: Jun 6, 2019
Words: 1256|Pages: 3|7 min read
Published: Jun 6, 2019
Most of The tumors have markers in blood and serum which can be monitored [65,66]. An electrochemical immunosensor is special device applied for tracking of some diseases, in which a sandwich immunoreaction is commonly applied on an electrode surface (see Figure 6), such as a tracer-antibody, a capture antibody, and the antigen. On the base of the inflammatory response or antigen-antibody reaction, the characteristic marker exists. Dixit et al. proposed electrochemistry-based methods for cancer distinguish [68] with high sensitivity, low cost, automated multiplexed protein immunoassays.
Beitollahi et, al; reported about A novel electrochemical immunosensor based on carbon paste electrode (CPE) generated of ionic liquid (IL) and graphite was manufactured. It showed good efficiency for rapid (each test in 30 s) determination of thyroid stimulating hormone (TSH). Electrode surface was corrected by gold nanoparticles for immobilizing of the thyroid stimulating hormone antibody (anti-TSH) on the CPE. The immunoassay structure was settled with sandwiching the antigen (TSH) between the thyroid stimulating hormone antibody on the CPE surface corrected by gold nanoparticles and the secondary antibody, polyclonal anti-human-TSH which has labeled with horseradish peroxidase (HRP-labeled anti-TSH). They announced, high sensitivity and acceptable stability were yielded with this immunosensor which is promising in the clinical assay of TSH.
Nowadays magnetic beads have been coming as a help. they have been applied for the configuration of biosensing devices to support bioreaction or carriers [63,77] for their wide surface area and their biocompatibility. In, another study catalytic bionanolabel was examined [92] .they has suggested that it used in the detection of B. anthracis Sap antigen. Bimetallic gold-palladium nanoparticles (Au-Pd NPs) were grown in situ on a boron nitride nanosheet (BNNS) which has been corrected by diallyldimethylammonium chloride, and then the Au-Pd NPs@BNNSs conjugated with the mouse anti-B. anthracis Sap antibodies (Ab2). Meanwhile, the use of graphene (GR) nanomaterial has focused on electron transfer which is a remarkable nanomaterial with two-dimensional sheets of sp2-hybridized C atoms in hexagonal configuration [92].
Rawat et, al; has suggested The electrochemical biosensor as a label-free detection of bovine serum albumin (BSA). By developing the electrochemical sensor gold coated polycarbonate membrane of different 30, 50 and 100 nm pore sizes and was observed that 30 nm pore size membrane exhibited better result than 50 and 100 nm pore size membrane. They make polycarbonate membranes coated by gold and thiolated by 16-Mercaptohexadecanoic acid (MHDA) as well as activated by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-Hydroxysuccinimide (NHS) for the binding of the antibody (BSA).
Highly sensitive gold nanoparticle based electrochemical biosensor for detection of Antigen antibody interactions Anita Rawat, K. P. Singh, Pashupat Vasmatkar and Pratibha Baral – Biochemical Communication-2017 additionally, AuNPs with remarkable properties can be not only a electroactive labeling, also Zhao et al. [87] applied them by both gold nanoparticles and enzymatic catalysis which dual signal reinforcing of electrochemical biosensor. The lectin-based biosensor array was used to evaluate the glycan.
As disease remedy examinations related to immunoassay are performed due to the interest in electrochemical biosensors for more vast applications with better performance [88–90]. As an example, the prostate antigen detected by three different generations ferrocene cored polyamidiamine Dendrimers gold electrode as an immunosensor[90].
Recently the number of DNA/RNA biosensor rise up which used to detect human immunodeficiency and oral cancers. Lanthanide polymer-labelled antibodies were studied to modify the analytical figures of merit of homogeneous immunoassays by inductively coupled plasma mass spectrometry (ICP-MS) which is tracking for multiplexed biomarker analysis in human serum samples. Different polymer-based lanthanide group is labelling Specific monoclonal antibodies against four cancer biomarkers (CEA, sErbB2, CA 15.3 and CA 125) and increasing the number of metal labels per binding site. And the size-exclusion chromatography separated them after the immunoreaction of the biomarkers with the specific antibodies, antigen-antibody complexes also tracking by ICP-MS detection.
Talemi et, al; introduced a method by targeting DNA with an inexpensive spectrophotometric detecting. They have immobilized thiol modified ss-DNA onto gold nanoparticles. In this method linear range of the developed biosensor for designation of supplementary target DNA was from 1 to 300 nM with a tracking limit of 0.6 nM.
A novel colorimetric DNA biosensor for genetic assay purpose based on gold nanoparticles self-assembled onto a functionalized glass surface Rasoul Pourtaghavi Talemi,Seyed Mehdi Mousavi- Journal of the Taiwan Institute of Chemical Engineers-2017- doi.org/10.1016/j.jtice.2017.04.027
In 2017, Li et, al; have presented a colorimetric biosensor which amplified for circulating tumor DNA (ctDNA). The biosensor intercommunicates the hybridization chain reaction (HCR) amplification by G-Quadruplex DNAzymes activity through triplex DNA formation. And it is in the presence of ctDNA, HCR occurs. They use triplex DNA forming as the pivot to unify nucleic acid amplification and DNAzymes for producing a high sensitive signal and low background. The colorimetric sensing platform is used in human blood plasma, a kind of complex biological environments, for ctDNA tracking, with a detection limit corresponding to 0.1 PM.
Ultrasensitive colorimetric detection of circulating tumor DNA using hybridization chain reaction and the pivot of triplex DNA Ruimin Li, Li Zou, Yanwei Luo, Manjun Zhang & Liansheng Ling-2017-scientific reportes To have the label-free colorimetric tracking of DNAs/RNAs based on self-assembling target species in the attendance of thiolated probes, a modified non-cross-linking gold-nanoparticles (Au-NPs) aggregation strategy has been improved.
These yields have a high dependency for the surface of Au-NPs and support the surface from salt-induced aggregation. To measuring the assay efficacy, the targeted was a small part of the citrus tristeza virus (CTV) genome, leading to a tracking limit of about 5 × 10−9 mol.L−1 over a linear range from 20 × 10−9 to 10 × 10−7 mol.L−1.
The disulfide reaction approach and complementary self-assembled DNAs/RNAs targets with simple AuNPs as a sensitive indicator supply a powerful and simple visual tracking tool for a wide range of applications.
Disulfide-induced self-assembled targets: A novel strategy for the label free colorimetric detection of DNAs/RNAs via unmodified gold nanoparticle -Ehsan Shokri, Morteza Hosseini, Mehdi D. Davari, Mohammad R. Ganjali, Maikel P. Peppelenbosch & Farhad Rezaee-2017-scientific reportes Kon et, al; Anounnced that they developed electrochemical microfluidic devices constructed Au-Ag bimetallic nanoparticles on single-walled carbon nanotube (SWCNT) electrodes for lower precise, more rapid and non-enzymatic electrochemical tracking of hydrogen peroxide (H2O2). To analysis, diluted antiseptic solutions containing 3 wt% H2O2 were used to estimate the concentration of H2O2 in the pharmaceutical sample. The results ranged from 97% to 107%, with below 5% relative standard deviations.
A cell-based electrochemical biosensor was improved to estimate the antioxidant activity of Asp-Leu-Glu-Glu (DLEE). The antioxidant segregated from dry-cured Chinese Xuanwei ham. A platinized gold electrode (Pt NPs/GE) covered with silver nanowires (Ag NWs) was manufactured to tracking H2O2 using redox signaling by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Xing et, al; announced This is a sensitive and simple system with the property to measure the antioxidant activity of peptides by tracking of H2O2 in the cell membrane.
Caco-2 cell-based electrochemical biosensor for evaluating the antioxidant capacity of Asp-Leu-Glu-Glu isolated from dry-cured Xuanwei ham Lujuan Xing,Qingfeng Ge,Donglei Jiang,Xiaoge Gao,Rui Liu,Songmin Cao,Xinbo Zhuang,Guanghong Zhoua Wangang Zhang-2018- Biosensors and Bioelectronics-doi.org/10.1016/j.bios.2018.01.020
The biosensor is applied to evaluate the antioxidant capacity of cell-free extracts from Lactobacillus plantarum strains segregated from Chinese dry-cured ham. The biosensor on the base of the evaluation of cellular reactive oxygen species (ROS) to indirectly determine changes in intracellular oxidative stress level as influenced by L. plantarum strains. A one-step acidified manganese dioxide (a-MnO2) improved gold electrode (GE) was applied to immobilize RAW 264.7 macrophage cells, which in next step encapsulated in a 3D cell culture system generated of alginate/ graphene oxide (NaAlg/GO).
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