Plasmonic Enhancement Strategies for Light-Driven Microbe Inactivation

Abstract

Light can be an effective antimicrobial. UV-C light, in particular, is now commonly used to sterilize inanimate surfaces, water, and even air. Highly energetic light can, however, also lead to unwanted photodamage and be hazardous. Consequently, conventional light-mediated microbe inactivation is not suitable for all applications. Plasmonic nanostructures can enhance electromagnetic fields in the visible range of the electromagnetic spectrum and show unique light-induced responses that can drive strong antimicrobial effects even for wavelengths that without plasmonic enhancement have little to no antimicrobial impact. Plasmonic nanostructures offer thus a potential strategy to expand the antimicrobial effect of light to wavelength and intensity ranges in which light-associated collateral damages are lower. This Perspective examines selected plasmon-enhanced antimicrobial strategies, elucidates the underlying physicochemical mechanisms, and discusses applications.

Synthesis and Photothermal Properties of UV-Plasmonic Group IV Transition Metal Carbide Nanoparticles

“…Plasmonic nanomaterials can efficiently convert absorbed light into heat through a phenomenon commonly known as the photothermal effect. , While there have been reports of plasmonic materials taking advantage of the UV-induced photothermal effect, − a direct efficiency has not been calculated using UV illumination. We believe it offers important insight into the plasmonic nature of such materials and therefore explored it for the group IV TMCs.…”

Plasmonic photoreactors-coated plastic tubing as combined-active-and-passive antimicrobial flow sterilizer

“…9,12 The former typically involves nanostructured hydrophobic compounds to generate anti-fouling properties and trigger bacterial growth inhibition, [13][14][15] whereas the latter comprises a range of different strategies, including antibacterial polymers, proteins and peptides, 16,17 functional polymers or surfactants that lyse the microbes, [18][19][20][21][22] carbon-based materials such as graphene 23 and fullerene 24 for mechanical, photochemical, or photothermal inactivation, or metal-based nanostructures that can release metal cations as bactericides or that trigger photophysical inactivation pathways. 12,[25][26][27][28][29] Silver nanoparticles (NPs) are effective generic antibacterial agents [30][31][32][33][34] and represent the most commonly used metal-based antimicrobial coating. 12,24,27,29,35 Silver NPs were found to sustain not only light-independent antibacterial effects, such as the release of Ag + , 30,33,36 binding to bacterial surfaces, 37 permeation of bacteria cell bodies for inducing intracellular damages, 38 or synergistic enhancement of antibiotics, 39 but also light-dependent effects through plasmonic photodynamic chemotherapy (PDCT), [30][31][32] photothermal, 40 and...…”