Plasmonic Nanotweezers and Nanosensors for Point‐of‐Care Applications

Abstract

The capabilities of manipulating and analyzing biological cells, bacteria, viruses, deoxyribonucleic acids (DNAs), and proteins at high resolution are significant in understanding biology and enabling early disease diagnosis. The progress in developments and applications of plasmonic nanotweezers and nanosensors is discussed, where the plasmon‐enhanced light‐matter interactions at the nanoscale improve the optical manipulation and analysis of biological objects. Selected examples are presented to illustrate their design and working principles. In the context of plasmofluidics, which merges plasmonics and fluidics, the integration of plasmonic nanotweezers and nanosensors with microfluidic systems for point‐of‐care (POC) applications is envisioned. Perspectives on the challenges and opportunities in further developing and applying the plasmofluidic POC devices are provided.

Heat-Mediated Optical Manipulation

“…Plasmonic tweezers exploit the plasmon-enhanced concentration and enhancement of light at the plasmonic nanostructures to trap nanometer-sized objects with nanoscale accuracy. , However, because surface plasmons are confined within the vicinity of the nanostructures, it is usually difficult to trap objects away from the nanostructures and to achieve 3D dynamic manipulation. One of the approaches to improving the plasmonic trapping efficiency is to couple plasmonic tweezers with microfluidics, which has developed into a field known as plasmofluidics. − Using project light patterns to form virtual electrodes on a photosensitive substrate, optoelectronic tweezers manipulate micro- and nanoscale objects based on dielectrophoresis. ,,, They combine the advantages of optical tweezers and electrode-based dielectrophoresis to achieve arbitrary manipulation of objects in 2D with simple and low-power optics. Photocatalytic motors are fueled by light-driven catalytic chemical reactions. , With the capacity for organic pollutant degradation that could be driven by sunlight, these motors are promising for environmental remediation .…”

SARS-CoV-2 detecting rapid metasurface-based sensor

“…The graphene due to its high conductivity and tuning characteristics can provide higher sensitivity which results in effective detection. Detection suing biosensors may come in handy due to their multipurpose applications including sensing, and encryption [19][20][21]. Graphene biosensors can be used in photovoltaic devices, defense, and medicinal applications [22][23][24].…”

Rational Fabrication of Ag Nanocone Arrays Embedded with Ag NPs and Their Sensing Applications

“…The collective oscillations of the conduction electrons in metallic nanostructures are known as SP resonance (SPR). − The size, shape, and structure of the nanostructures and the dielectric characteristics of the external environment significantly impact the SPR’s position and intensity. − Plasmonic metallic nanostructures can be used to make optical sensors because of their wide range of response factors. Thus, the use of plasmon-enhanced optical sensors for analyte detection in biological diagnosis, homeland security, food safety, and environmental control is expanding. − …”