Noble Metal Nanoparticles-Based Colorimetric Biosensor for Visual Quantification: A Mini Review

Abstract

Nobel metal can be used to form a category of nanoparticles, termed noble metal nanoparticles (NMNPs), which are inert (resistant to oxidation/corrosion) and have unique physical and optical properties. NMNPs, particularly gold and silver nanoparticles (AuNPs and AgNPs), are highly accurate and sensitive visual biosensors for the analytical detection of a wide range of inorganic and organic compounds. The interaction between noble metal nanoparticles (NMNPs) and inorganic/organic molecules produces colorimetric shifts that enable the accurate and sensitive detection of toxins, heavy metal ions, nucleic acids, lipids, proteins, antibodies, and other molecules. Hydrogen bonding, electrostatic interactions, and steric effects of inorganic/organic molecules with NMNPs surface can react or displacing capping agents, inducing crosslinking and non-crosslinking, broadening, or shifting local surface plasmon resonance absorption. NMNPs-based biosensors have been widely applied to a series of simple, rapid, and low-cost diagnostic products using colorimetric readout or simple visual assessment. In this mini review, we introduce the concepts and properties of NMNPs with chemical reduction synthesis, tunable optical property, and surface modification technique that benefit the development of NMNPs-based colorimetric biosensors, especially for the visual quantification. The “aggregation strategy” based detection principle of NMNPs colorimetric biosensors with the mechanism of crosslinking and non-crosslinking have been discussed, particularly, the critical coagulation concentration-based salt titration methodology have been exhibited by derived equations to explain non-crosslinking strategy be applied to NMNPs based visual quantification. Among the broad categories of NMNPs based biosensor detection analyses, we typically focused on four types of molecules (melamine, single/double strand DNA, mercury ions, and proteins) with discussion from the standpoint of the interaction between NMNPs surface with molecules, and DNA engineered NMNPs-based biosensor applications. Taken together, NMNPs-based colorimetric biosensors have the potential to serve as a simple yet reliable technique to enable visual quantification.

Nanomaterial-mediated paper-based biosensors for colorimetric pathogen detection

“…These features consist of high surface-to-volume ratio which enables suitable surface modification with bioactive compounds, excellent capacity for reaction catalysis, electrical conductance, good biocompatibility, particularly high characteristic extinction coefficient in visible light, as well as visual color transition from the shift of surface plasma absorption by varying size, shape, interparticle distance through the aggregation, and dielectric environment [ 13 , 26 ]. The deployment of noble metal nanoparticles in colorimetric biosensors can significantly amplify signal intensity and thus enhance the sensitivity for target biological molecules such as pathogenic bacteria and viruses, DNA, toxins, proteins, and others [ 26 , 39 ]. Among noble metal nanoparticles, gold and silver nanoparticles are particularly interesting due to their simplicity in producing a color response with high sensitivity [ 39 ].…”

“…The deployment of noble metal nanoparticles in colorimetric biosensors can significantly amplify signal intensity and thus enhance the sensitivity for target biological molecules such as pathogenic bacteria and viruses, DNA, toxins, proteins, and others [ 26 , 39 ]. Among noble metal nanoparticles, gold and silver nanoparticles are particularly interesting due to their simplicity in producing a color response with high sensitivity [ 39 ]. Gold nanoparticles (AuNPs) are extensively used in colorimetric biomedical assays since they are easy to synthesize, are chemically and physically stable, have good biocompatibility, have unique optoelectronic behavior, and are easily modified with bioactive and organic compounds [ 13 , 40 ].…”

Hollow Gold-Silver Nanoshells Coated with Ultrathin SiO2 Shells for Plasmon-Enhanced Photocatalytic Applications

“…Regardless of the pinhole formation typically observed during the aforementioned process, the GS-NSs retained a diameter of 50-60 nm after the galvanic replacement reaction. The change observed in the morphology of the noble nanoparticles has an effect on their tunable optical properties, which leads to advantages in various kinds of optical applications, including enhanced photocatalysis in a specific region of light, and photothermal treatments and colorimetric sensors [24][25][26]. Figure 2 illustrates the extinction spectra of silver nanoparticles and GS-NSs prepared using three different amounts of K-Au solution.…”

Development of label-free gold nanoparticle based rapid colorimetric assay for clinical/point-of-care screening of cervical cancer

“…This technique involves an analyte triggered aggregation (such as electrostatic or hydrogen bonding interaction) of Au NPs. 23,[27][28][29][30] They are cost-effective and require minimal time for sample processing, hence more suitable for point-of-care applications. Sina et al developed a colorimetric technique for detection of methylscape biomarker using cancer genomes.…”