Morphological Evolution of Gold Nanoparticles into Nanodendrites Using Catechol-Grafted Polymer Templates

Abstract

Morphology, dimension, size, and surface chemistry of gold nanoparticles are critically important in determining their optical, catalytic, and photothermal properties. Although many techniques have been developed to synthesize various gold nanostructures, complicated and multistep procedures are required to generate three-dimensional, dendritic gold nanostructures. Here, we present a simple method to synthesize highly branched gold nanodendrites through the well-controlled reduction of gold ions complexed with a catechol-grafted polymer. Dextran grafted with catechols guides the morphological evolution as a polymeric ligand to generate dendritic gold structures through the interconnection of the spherical gold nanoparticles. The reduction kinetics, which is critical for morphological changes, is controllable using dimethylacetamide, which can decrease the metal–ligand dissociation and gold ion diffusivity. This study suggests that mussel-inspired polymer chemistry provides a simple one-pot synthetic route to colloidal gold nanodendrites that are potentially applicable to biosensing and catalysis.

Catechol as a Universal Linker for the Synthesis of Hybrid Polyfluorene/Nanoparticle Materials

“…When directly attached to the CPs, which is possible using CTCP in combination with an external catechol-based initiator, the catechol linker retains the conjugation. Small catechol-based molecules and some nonCPs have shown to bind to a variety of commonly used inorganic NPs such as CdS, CdSe, TiO 2 , Fe 3 O 4 , , Au, and ZnO . In addition, we have already prepared a catechol-functionalized poly­(3-alkylthiophene) using a Kumada CTCP (KCTCP) in combination with a catechol external initiator and have proven the formation of a stable coupling to magnetite (Fe 3 O 4 ) NPs .…”

A New Ratiometric Fluorescent Probe for Specific Monitoring of hROS under Physiological Conditions Using Boric Acid-Protected l-DOPA Gold Nanoclusters

“…Catethol could serve as a reducing agent for noble metal nanostructures and exhibited an exceptional binding affinity to various metallic substrates via metal−catechol complexation. 18 L-3,4-Dihydroxyphenylalanine (L-DOPA) is the precursor of dopamine, a biological micromolecule neurotransmitter commonly known for its use in the treatment of Parkinson's disease. 19 The electron-rich groups (−COOH, −NH 2 ) and the catechol group of L-DOPA made it as an admirable candidate for the synthesis of AuNCs with both reducing capacity and coordination ability to Au.…”

“…Catethol could serve as a reducing agent for noble metal nanostructures and exhibited an exceptional binding affinity to various metallic substrates via metal–catechol complexation .…”

Therapeutic nanodendrites: current applications and prospects

“…The high density of defects on the surface may contribute to a signicantly improved surface area to volume ratio when compared to smooth surface nanocrystals. 11,12 These defects can provide multiple binding sites on a single branch of a nanodendrite with numerous interconnected sub-branches, 13 thereby making it possible to achieve excellent features for multivariant applications such as catalysis, 14 drug delivery, 15 and hyperthermia cancer therapy. 16 As an example, nanodendrites have recently been reported to form various assemblies, including monometallic, bimetallic, and in a few cases trimetallic nanodendrites with superior tunable shapedependent properties.…”