A novel colorimetric biosensor for rapid detection of dengue virus upon acid-induced aggregation of colloidal gold

Abstract

The dengue virus, once transmitted to people through a mosquito bite, causes an infectious disease called dengue fever. The dengue fever can develop into two fatal syndromes, namely dengue shock...

A simple and rapid colorimetric detection of Staphylococcus aureus relied on the distance-dependent optical properties of silver nanoparticles

“…In fact, the absorbance of the DNA probe could be facilitated by using low pH. 12,18 The usage of the low pH technique has three characteristics. Firstly, it reduces the repulsion between DNA and noble metal nanoparticles, leading to faster absorption kinetics.…”

“…After that, the AgNPs were conjugated with the as-prepared thiolated DNA by the pH-assisted method, as depicted in the previous research, with minor conversions. 12,18 In a typical experiment, 1 μL of DNA probe was thoroughly mixed with 1 mL of AgNPs, followed by adding 53 μL of citrate buffer (100 mM, pH 3). The solution was incubated at ambient temperature for 5 minutes before adding 56.6 μL of the same buffer.…”

“…Nanostructures in biosensors are now extremely promising due to the significantly increasing biosensor performance. 10–12 Silver nanoparticles, as reported, have exceptional surface-enhanced Raman scattering (SERS) characteristics and localized surface plasmon resonance (LSPR) light scattering, high molar extinction coefficient, and the ability to functionalize with a variety of biomolecules that can provide fast, accurate, and one-step detection of pathogens. 13,33 Colorimetric assays utilizing silver nanostructures involve functionalizing the nanoparticles with bio-receptors specific to the complementary sequence in the target.…”