A Review on Gold Nanotriangles: Synthesis, Self-Assembly and Their Applications

Abstract

Gold nanoparticles (AuNPs) with interesting optical properties have attracted much attention in recent years. The synthesis and plasmonic properties of AuNPs with a controllable size and shape have been extensively investigated. Among these AuNPs, gold nanotriangles (AuNTs) exhibited unique optical and plasmonic properties due to their special triangular anisotropy. Indeed, AuNTs showed promising applications in optoelectronics, optical sensing, imaging and other fields. However, only few reviews about these applications have been reported. Herein, we comprehensively reviewed the synthesis and self-assembly of AuNTs and their applications in recent years. The preparation protocols of AuNTs are mainly categorized into chemical synthesis, biosynthesis and physical-stimulus-induced synthesis. The comparison between the advantages and disadvantages of various synthetic strategies are discussed. Furthermore, the specific surface modification of AuNTs and their self-assembly into different dimensional nano- or microstructures by various interparticle interactions are introduced. Based on the unique physical properties of AuNTs and their assemblies, the applications towards chemical biology and sensing were developed. Finally, the future development of AuNTs is prospected.

Tau- and α-synuclein-targeted gold nanoparticles: applications, opportunities, and future outlooks in the diagnosis and therapy of neurodegenerative diseases

“…The most common synthesis is the seed-mediated method using CTAB as a stabilizer agent [ 86 ], allowing to modulate the plasmon maximum, absorption, and scattering efficiency of the nanosystem [ 87 , 88 ]. Gold nanoprisms (GNPr) also exhibit a plasmon that can be modulated in the biological window [ 89 ], but their synthesis is more friendly using sodium thiosulfate as a reducing and stabilizing agent [ 90 ]. Also, they scatter the light efficiently due to the greater number of hot spots, making them potential candidates as fluorescent probes in imaging [ 91 ].…”

Biohybrid materials comprising an artificial peroxidase and differently shaped gold nanoparticles

“…Among the various gold nanomaterials available, we selected gold nanorods and triangular gold nanoprisms, as they can be easily produced using several well-developed and scalable methods. 18,[68][69][70] Further, as their surfaces can be manipulated and tuned with a variety of coating shells, 18,35 they are optimal candidates for enzyme immobilization. This choice allows studying nanomaterials with distinct properties, specically the sharp edges of nanoprisms and the smooth surfaces of nanorods.…”

Depletion force optimization for high-purity gold nanotriangles prepared using different growth methods

“…17,18 Gold nanotriangles (AuNTs) have also been synthesized using seed-mediated and seedless growth methods. 13,14,16,17,[19][20][21][22] Recent progress in the high-yield synthesis of AuNTs has made them easier to handle. 13,16,20,22 Because of their anisotropic triangular form, AuNTs exhibit unique LSPR characteristics that cause hotspots at the corners, edges, and faces depending on the LSPR mode, which depends on the resonance against the incident light.…”

“…13,14,16,17,[19][20][21][22] Recent progress in the high-yield synthesis of AuNTs has made them easier to handle. 13,16,20,22 Because of their anisotropic triangular form, AuNTs exhibit unique LSPR characteristics that cause hotspots at the corners, edges, and faces depending on the LSPR mode, which depends on the resonance against the incident light. [23][24][25] The resonant energy of each LSPR mode in AuNTs may be modied by varying the length of the AuNT sides; the LSPR peak wavelength can modulate between 600 and 1300 nm.…”

“…[23][24][25] The resonant energy of each LSPR mode in AuNTs may be modied by varying the length of the AuNT sides; the LSPR peak wavelength can modulate between 600 and 1300 nm. 22 The anisotropic plate also exhibits unique assembled structures with edge-to-edge 13,16,20 and face-to-face 26 assemblies, resulting in a two-dimensional superstructure and a one-dimensional shuttle structure, respectively.…”