An easy way to detect dengue virus using nanoparticle-antibody conjugates

Abstract

The aim of the present research is to propose a new method based on localized surface plasmon resonance (LSPR) for fast dengue virus detection. A pool with four dengue serotypes (DENV-1, -2, -3, -4) was detected through antigen-antibody binding using gold nanoparticles (AuNPs) as signaling antibody carriers. Such result was confirmed through surface plasmon resonance (SPR), transmission electron microcopy (TEM), and dynamic light scattering (DLS) techniques. The limit of detection was calculated for TCID 10 demonstrating a linear correlation between viral concentration and number of cells with an r value of > 0.993. The assay presented good sensibility and reproducibility of results and the negative controls were not mistakenly detected. This design requires no pretreatment or high trained person. In the future, it can be used in commercial antibody detection kits.

A Methodology for Porcine Circovirus 2 (PCV-2) Quantification Based on Gold Nanoparticles

“…Based on this graph analysis, it was possible observing an absorbance peak intensity decrease and wavelength shift in samples with higher PCV-2 concentrations. Similar results were observed by Basso et al [18] and Wang and Irudayaraj [31], and they can be explained by the difficult interaction between light photons and electrons in the conduction band (free electrons), resulting in a decrease in the absorbance peak and wavelength shift [32]. The calibration curve of the five PCV-2 concentrations (10 5 , 10 6 , 10 7 , 10 8 , and 10 9 DNA copies/mL virus) showed an R 2 value of 0.99 ( Figure 4B).…”

“…EDX analysis showed a new sulfur peak (S) relative to the thiol group ( Figure 5D). Similar results were found by Basso et al [18], who observed SAMs formation in a hybrid nanoparticle composed of iron and gold. Microscopy image 5E showed the AuNPs/SAMs/antibody complex and the bead diameter increased to 30 nm, which indicated antibody presence.…”

“…This drop in behavior at the absorbance peak in solutions with higher antibody concentrations, as shown in the graph, was also reported in studies by Basso et al [18] and Wang and Irudayaraj [31]. This response happens because the more modified the AuNPs surface, the harder it is for the laser light of the equipment to interact with its surface.…”

“…The synthesis of gold nanoparticles was based on Basso et al [18]. An Erlenmeyer glass placed on a magnetic stirrer had 10 mL of HAuCl 4 solution (1 mM) added, which was stirred at 100 • C to the Materials 2020, 13, 1087 4 of 13 boiling point.…”

Reduced Graphene Oxide Decorated with AuNPs as a New Aptamer-Based Biosensor for the Detection of Androgen Receptor from Prostate Cells

“…These metallic nanoparticles include palladium [33], antimony [34], silver [35], and gold [36], due to their enhanced characteristics [37]. In this way, the gold nanoparticles (AuNPs) are a powerful candidate to be conjugated with graphene, because it is a noble product with unique characteristics of biocompatibility, low toxicity, electrical features, and catalytic and surface-enhanced Raman properties; moreover, the AuNPs can be easily modified with biological samples (for example, nucleic acids (DNA or RNA), proteins, enzymes, and antibodies) making them a robust platform to be used for immunoassays, thermotherapy, hormones, pesticides, proteins, and virus and bacteria detection [38][39][40].…”