Plasmonic Gold Nanoisland Film for Bacterial Theranostics

Abstract

Plasmonic nanomaterials have been intensively explored for applications in biomedical detection and therapy for human sustainability. Herein, plasmonic gold nanoisland (NI) film (AuNIF) was fabricated onto a glass substrate by a facile seed-mediated growth approach. The structure of the tortuous gold NIs of the AuNIF was demonstrated by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on the ultraviolet-visible spectrum, the AuNIF revealed plasmonic absorption with maximum intensity at 624 nm. With the change to the surface topography created by the NIs, the capture efficiency of Escherichia coli (E. coli) by the AuNIF was significantly increased compared to that of the glass substrate. The AuNIF was applied as a surface-enhanced Raman scattering (SERS) substrate to enhance the Raman signal of E. coli. Moreover, the plasmonic AuNIF exhibited a superior photothermal effect under irradiation with simulated AM1.5 sunlight. For photothermal therapy, the AuNIF also displayed outstanding efficiency in the photothermal killing of E. coli. Using a combination of SERS detection and photothermal therapy, the AuNIF could be a promising platform for bacterial theranostics.

Plasmonic Photocatalysis: Activating Chemical Bonds through Light and Plasmon

“…A key energy‐loss pathway in photoexcited plasmonic NP is through the dissipation of heat to the surrounding medium—termed as local or plasmonic heating. Such photothermal effects have been utilized in the area of photothermal catalysis, [ 147 ] photothermal ablation of tumor cells, [ 148,149 ] drug delivery, [ 150 ] magnetic recording, [ 151 ] solar‐vapor generation, [ 152–154 ] and even in SARS‐CoV‐2 detection. [ 155,156 ] However, the plasmon‐induced heat dissipation poses a complication while evaluating the photocatalytic activity of plasmonic NPs.…”

“…photothermal ablation of tumor cells, [148,149] drug delivery, [150] magnetic recording, [151] solar-vapor generation, [152][153][154] and even in SARS-CoV-2 detection. [155,156] However, the plasmon-induced heat dissipation poses a complication while evaluating the photocatalytic activity of plasmonic NPs.…”

Development of Gold Nanoparticle-Based SERS Substrates on TiO2-Coating to Reduce the Coffee Ring Effect

“…In literature, a high variety of morphologies of nanoparticles are used for SERS. Nanodots [ 11 ], nanotriangles [ 12 ], nanocubes [ 13 ], nanostars [ 14 ], nanopillars [ 15 ], nanorods [ 16 ], nanopopcorns [ 17 ], nanosponges [ 18 ], nanomushrooms [ 19 ], nano-islands [ 20 ], bioinspired micropatterned Au-Areoles [ 21 ] and spherical nanoparticles [ 8 , 22 , 23 , 24 , 25 ] are often used in this context. A very common synthesis described by Turkovich et al, which is based on the reduction of chloroauric acid with sodium citrate and was modified several times over the years [ 26 , 27 , 28 , 29 ].…”

A Co-Printed Nanoslit Surface Plasmon Resonance Structure in Microfluidic Device for LMP-1 Detection

“…Many types of biosensors (e.g., electrochemical [ 3 , 4 , 5 , 6 ], immunobeads motion [ 7 , 8 , 9 ], mechanical, optical types [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ] etc.) have been developed and show the potential for becoming portable.…”