scholarly journals Multivalent Lactose–Ferrocene Conjugates Based on Poly(Amido Amine) Dendrimers and Gold Nanoparticles as Electrochemical Probes for Sensing Galectin-3

2020 ◽  
Author(s):  
Manuel C. Martos-Maldonado ◽  
Indalecio Quesada-Soriano ◽  
Luis García-Fuentes ◽  
Antonio Vargas-Berenguel
Keyword(s):  
Gold Nanoparticles ◽  
Surface Modification ◽  
Cardiac Remodeling ◽  
Building Blocks ◽  
Differential Pulse ◽  
Pamam Dendrimers ◽  
Titration Calorimetry ◽  
Vis Spectroscopy ◽  
Galectin 3 ◽  
Pulse Voltammetry

Galectin-3 is considered a cancer biomarker and bioindicator of fibrosis and cardiac remodeling, and, therefore, it is desirable to develop convenient methods for its detection. Herein, an approach based on the development of multivalent electrochemical probes with high galectin-3 sensing abilities is reported. The probes consist of multivalent presentations of lactose–ferrocene conjugates scaffolded on poly(amido amine) (PAMAM) dendrimers and gold nanoparticles. Such multivalent lactose–ferrocene conjugates are synthesized by coupling of azidomethylferrocene-lactose building blocks on alkyne-functionalized PAMAM, for the case of the glycodendrimers, and to disulfide‐functionalized linkers that are then used for the surface modification of citrate-stabilized gold nanoparticles. The binding and sensing abilities towards galectin 3 of both ferrocene-containing lactose dendrimers and gold nanoparticles have been evaluated by means of isothermal titration calorimetry, UV-vis spectroscopy, and differential pulse voltammetry. The highest sensitivity by electrochemical methods to galectin-3 was shown by lactosylferrocenylated gold nanoparticles, which are able to detect the lectin in nanomolar concentrations.

scholarly journals Multivalent Lactose–Ferrocene Conjugates Based on Poly (Amido Amine) Dendrimers and Gold Nanoparticles as Electrochemical Probes for Sensing Galectin-3

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 203 ◽  
Author(s):  
Manuel C. Martos-Maldonado ◽  
Indalecio Quesada-Soriano ◽  
Luis García-Fuentes ◽  
Antonio Vargas-Berenguel
Keyword(s):  
Gold Nanoparticles ◽  
Surface Modification ◽  
Cardiac Remodeling ◽  
Building Blocks ◽  
Differential Pulse ◽  
Pamam Dendrimers ◽  
Titration Calorimetry ◽  
Vis Spectroscopy ◽  
Galectin 3 ◽  
Pulse Voltammetry

Galectin-3 is considered a cancer biomarker and bioindicator of fibrosis and cardiac remodeling and, therefore, it is desirable to develop convenient methods for its detection. Herein, an approach based on the development of multivalent electrochemical probes with high galectin-3 sensing abilities is reported. The probes consist of multivalent presentations of lactose–ferrocene conjugates scaffolded on poly (amido amine) (PAMAM) dendrimers and gold nanoparticles. Such multivalent lactose–ferrocene conjugates are synthesized by coupling of azidomethyl ferrocene–lactose building blocks on alkyne-functionalized PAMAM, for the case of the glycodendrimers, and to disulfide-functionalized linkers that are then used for the surface modification of citrate-stabilized gold nanoparticles. The binding and sensing abilities toward galectin-3 of both ferrocene-containing lactose dendrimers and gold nanoparticles have been evaluated by means of isothermal titration calorimetry, UV–vis spectroscopy, and differential pulse voltammetry. The highest sensitivity by electrochemical methods to galectin-3 was shown by lactosylferrocenylated gold nanoparticles, which are able to detect the lectin in nanomolar concentrations.

Endocytosis and exocytosis processes of gold nanoparticle with erythrocyte ghosts

MRS Advances ◽  
2020 ◽  
Vol 5 (42) ◽  
pp. 2169-2172 ◽  
Author(s):  
Víctor Gómez Flores
Keyword(s):  
Gold Nanoparticles ◽  
Surface Modification ◽  
Sem Analysis ◽  
Erythrocyte Ghosts ◽  
Simple Diffusion ◽  
Membrane Interaction ◽  
Vis Spectroscopy ◽  
Plasmatic Membrane ◽  
Result Show ◽  
Spherical Gold Nanoparticles

AbstractThe interaction of spherical gold nanoparticles (AuNPs) of 20nm elaborated by Turkevich method with the erythrocytes ghosts (7-8 μm) cell membrane was evaluated. The AuNPs-Membrane interaction was determined using confocal microscope, Uv-Vis spectroscopy and SEM analysis. The result show that nanoparticles larger than 20nm are adhered to the erythrocyte ghost membrane due their size and surface modification. Smaller AuNPs enter onto the cell by simple diffusion through the plasmatic membrane voids, these data may favor the best design and application in the treatments applied in biomedicine.

scholarly journals Salivary Cortisol Determination on Smartphone-Based Differential Pulse Voltammetry System

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1422 ◽  
Author(s):  
Jingjing Liu ◽  
Ning Xu ◽  
Hong Men ◽  
Shuang Li ◽  
Yanli Lu ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Differential Pulse Voltammetry ◽  
Salivary Cortisol ◽  
Specific Binding ◽  
Point Of Care ◽  
Covalent Binding ◽  
Differential Pulse ◽  
Current Response ◽  
Non Invasive ◽  
Pulse Voltammetry

Cortisol is commonly used as a significant biomarker of psychological or physical stress. With the accelerated pace of life, non-invasive cortisol detection at the point of care (POC) is in high demand for personal health monitoring. In this paper, an ultrasensitive immunosensor using gold nanoparticles/molybdenum disulfide/gold nanoparticles (AuNPs/MoS2/AuNPs) as transducer was explored for non-invasive salivary cortisol monitoring at POC with the miniaturized differential pulse voltammetry (DPV) system based on a smartphone. Covalent binding of cortisol antibody (CORT-Ab) onto the AuNPs/MoS2/AuNPs transducer was achieved through the self-assembled monolayer of specially designed polyethylene glycol (PEG, SH-PEG-COOH). Non-specific binding was avoided by passivating the surface with ethanolamine. The miniaturized portable DPV system was utilized for human salivary cortisol detection. A series current response of different cortisol concentrations decreased and exhibited a linear range of 0.5–200 nM, the detection limit of 0.11 nM, and high sensitivity of 30 μA M−1 with a regression coefficient of 0.9947. Cortisol was also distinguished successfully from the other substances in saliva. The recovery ratio of spiked human salivary cortisol and the variation of salivary cortisol level during one day indicated the practicability of the immunosensor based on the portable system. The results demonstrated the excellent performance of the smartphone-based immunosensor system and its great potential application for non-invasive human salivary cortisol detection at POC.

Gold Nanoparticle Based Electrochemical Immunosensor for Detection of T3 Hormone

2020 ◽  
Vol 20 (10) ◽  
pp. 6057-6062
Author(s):  
Rahul Saxena ◽  
H. Fouad ◽  
Sudha Srivastava
Keyword(s):  
Gold Nanoparticles ◽  
Cyclic Voltammetry ◽  
Electrode Surface ◽  
Dynamic Range ◽  
Limit Of Detection ◽  
Differential Pulse ◽  
Electrochemical Immunosensor ◽  
Antigen Concentration ◽  
Antigen Present ◽  
Pulse Voltammetry

We report a nanoparticles based electrochemical immunosensor to detect and quantify triiodothyronine (T3) hormone. Immunosensor developed using gold nanoparticles and anti-T3 antibody, was employed for quantification of T3 antigen using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) technique. The electrochemical response of the developed immunosensor correlates well with the amount of antigen present in the sample. With increase in antigen concentration the immunocomplex formation on electrode surface increases and hence redox current decreases. The immunosensor shows a lower limit of detection of 1 pg/mL and dynamic range from 1 to 500 pg/mL. Sensitivity of the immunosensor was found to be 29.81 μA/pg/mL/cm2.

scholarly journals β-Cyclodextrin-Immobilized Ni/Graphene Electrode for Electrochemical Enantiorecognition of Phenylalanine

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 777
Author(s):  
Feiyue Chen ◽  
Zhiqin Fan ◽  
Yangguang Zhu ◽  
Huifang Sun ◽  
Jinhong Yu ◽  
...  
Keyword(s):  
Surface Modification ◽  
Detection Limit ◽  
Vapor Deposition ◽  
Storage Stability ◽  
Chemical Vapor ◽  
Differential Pulse ◽  
Peak Shift ◽  
Single Step ◽  
Pulse Voltammetry ◽  
Electrochemical Recognition

In this work, a Ni/graphene (Ni/G) electrode was designed and fabricated by plasma-enhanced chemical vapor deposition (PECVD) for the ultrasensitive recognition of d- and l-phenylalanine. Through a single-step PECVD process, the Ni/G electrode can achieve better hydrophilicity and larger catalytic surface area, which is beneficial for the electrochemical recognition of bio-objects. After surface modification with β-cyclodextrin, the Ni/G electrode can distinguish d-phenylalanine from l-phenylalanine according to a 0.09 V peak shift in differential pulse voltammetry tests. Moreover, this Ni/G electrode achieved a detection limit as low as 1 nM and a wide linear range from 1 nM to 10 mM toward l-phenylalanine, with great storage stability and working stability.

scholarly journals Electrochemical Methods for Evaluation of Antioxidant Properties of Propolis Extract Incorporated in Chitosan Nanoparticles

2021 ◽  
Vol 57 (4) ◽  
pp. 96-108
Author(s):  
Luminita Fritea ◽  
Paula Melania Pasca ◽  
Laurian Vlase ◽  
Ana-Maria Gheldiu ◽  
Liviu Moldovan ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
High Performance ◽  
Antioxidant Properties ◽  
Chitosan Nanoparticles ◽  
Differential Pulse ◽  
Electrochemical Methods ◽  
Propolis Extract ◽  
Vis Spectroscopy ◽  
Pulse Voltammetry ◽  
Nano Formulation

The main purpose of our study was to demonstrate the antioxidant properties of novel propolis nano-formulation, incorporated in spherical chitosan nanoparticles. The electrochemical methods (cyclic voltammetry and differential pulse voltammetry) were successfully applied to propolis extract and nanopropolis formulation, confirming that the content in phenolic acids and flavonoids is responsible for the antioxidant activity of propolis. The quantitative and qualitative results are also supported by high performance liquid chromatography (HPLC) and ultraviolet-visible (UV-Vis) spectroscopy.

Sign in / Sign up

Export Citation Format

Share Document