Gold Nanoparticle-Based Colorimetric Strategies for Chemical and Biological Sensing Applications

Abstract

Gold nanoparticles are popularly used in biological and chemical sensors and their applications owing to their fascinating chemical, optical, and catalytic properties. Particularly, the use of gold nanoparticles is widespread in colorimetric assays because of their simple, cost-effective fabrication, and ease of use. More importantly, the gold nanoparticle sensor response is a visual change in color, which allows easy interpretation of results. Therefore, many studies of gold nanoparticle-based colorimetric methods have been reported, and some review articles published over the past years. Most reviews focus exclusively on a single gold nanoparticle-based colorimetric technique for one analyte of interest. In this review, we focus on the current developments in different colorimetric assay designs for the sensing of various chemical and biological samples. We summarize and classify the sensing strategies and mechanism analyses of gold nanoparticle-based detection. Additionally, typical examples of recently developed gold nanoparticle-based colorimetric methods and their applications in the detection of various analytes are presented and discussed comprehensively.

A Rapid Blood Test to Monitor the Immune Status Change of Dairy Cows and to Evaluate their Disease Risk during the Periparturient Period

“…The color change is due to the surface plasmon resonance shift in aggregated gold nanoparticles, a phenomenon that has been well studied and established for biosensing and diagnostic test applications [22][23][24][25]. In the presence of both IgG1 and IgG2, as in the case of bovine blood samples, the two proteins will compete to interact with the nanoparticles through the two different binding modes.…”

Gold Nanoparticles and Nanorods in Nuclear Medicine: A Mini Review

“…AuNPs can be synthesized by means of several processes such as chemical, physical, and biological methods [24,[49][50][51]65]. A well-known bottom-up approach is a wet reduction in the presence of a capping agent [55,57,[59][60][61][62]64].…”

“…Consequently, it is positive to develop active targeting systems that can selectively identify specific cells or tissues, attaching specific ligands such as antibodies, aptamers, peptides, and so forth, on nanocarrier surfaces [48,49].Among others, the gold-based nanomaterials have amazing features that make them very suitable and valuable in nanomedicine. In fact, they show remarkable chemical-physical properties, such as an easy modifiable morphology/size/surface, modulable optical absorption and scattering, photothermal and photoacoustic enhancements, and a wide surface/volume ratio that is suitable for interaction with the environment [50][51][52][53]. The gold surface can be functionalized and linked with drugs [54-57] and biomolecules, such as enzymes, antibodies, DNA, and peptides to achieve a specific site [58][59][60][61][62][63][64][65][66], and they are also studied to develop innovative antibacterial systems [67][68][69][70].In the wide field of advanced materials that represent the frontier where gold-based materials and nuclear medicine meet, this review provides an updated scenario of the progress in this young research field, focusing on gold nanoparticles (AuNPs) and nanorods (AuNRs) used in diagnosis and therapy, as schematized in Figure 1.…”

2-LED-µSpectrophotometer for Rapid On-Site Detection of Pathogens Using Noble-Metal Nanoparticle-Based Colorimetric Assays

“…In case of plasmonic nanoparticles, the extinction coefficient and the absorption cross section are several orders of magnitude higher compared with common dyes [2]. Therefore, colorimetric assays using plasmonic particles have an outstanding detection capability [3]. The absorption spectrum of plasmonic nanoparticles is usually in the visible range [4], which enables simple optical detection for the detection of various analytes.…”