Uniform Distance Scaling Behavior of Planet–Satellite Nanostructures Made by Star Polymers

Abstract

Planet-satellite nanostructures from RAFT star polymers and larger (planet) as well as smaller (satellite) gold nanoparticles are analyzed in experiments and computer simulations regarding the influence of arm number of star polymers. A uniform scaling behavior of planet-satellite distances as a function of arm length was found both in the dried state (via transmission electron microscopy) after casting the nanostructures on surfaces and in the colloidally dispersed state (via simulations and small-angle X-ray scattering) when 2-, 3-, and 6-arm star polymers were employed. This indicates that the planet-satellite distances are mainly determined by the arm length of star polymers. The observed discrepancy between TEM and simulated distances can be attributed to the difference of polymer configurations in dried and dispersed state. Our results also show that these distances are controlled by the density of star polymers end groups, and the number of grabbed satellite particles is determined by the magnitude of the corresponding density. These findings demonstrate the feasibility to precisely control the planet-satellite structures at the nanoscale.

Plasmonic Nanoassemblies: Tentacles Beat Satellites for Boosting Broadband NIR Plasmon Coupling Providing a Novel Candidate for SERS and Photothermal Therapy

“…The flexible ester bonds of polyethylene glycol branches of the linker makes it feasible for one polymeric linker to anchor one to three 5 nm NPs. The importance of the polymer flexibility on interparticle distance of the core–satellite nanoassemblies has also been pointed out by Rossner et al Importantly, the polymeric linker featuring a DLS average size of 2.5 ± 1.5 (i.e., 1−4) nm (see Figure S4 in the Supporting Information) creates a scenario of size overlap with some population of the 5 nm NP (i.e., 2−6 nm). The average polymer footprint is ≈5 nm 2 (2.5 nm diameter) with a range of 0.8−12 nm 2 (1−4 nm diameter) projecting onto a 5 nm NP having an average surface area of 80 nm 2 (a range of 12−113 nm 2 due to NP diameter of 2−6 nm).…”

“…In addition to the importance of the interacting nanostructures and the nanoassembly morphology, the interparticle distance, i.e., the nanogap is a critical governing factor . It has been established that sub 1 nm nanogaps allow realization of such properties . Therefore, in a quest to achieve such properties, linker mediated nanoassembly formation has been extensively researched where linker molecules of sub 1 nm sizes have gained importance.…”

“…[15][16][17][18][19] It has been established that sub 1 nm nanogaps allow realization of such properties. [18,20,21] Therefore, in a quest to achieve such properties, linker mediated nanoassembly formation has been Optical theranostic applications demand near-infrared (NIR) localized surface plasmon resonance (LSPR) and maximized electric field at nanosurfaces and nanojunctions, aiding diagnosis via Raman or optoacoustic imaging, and photothermal-based therapies. To this end, multiple permutations and combinations of plasmonic nanostructures and molecular "glues" or linkers are employed to obtain nanoassemblies, such as nanobranches and core-satellite morphologies.…”

Reconfigurable assembly of charged polymer-modified Janus and non-Janus particles: from half-raspberries to colloidal clusters and chains

“…Nevertheless, there are only few examples of reversible selfassembly of non-Janus 12,14,27,[33][34][35][36][37][38][39][40][41][42][43][44] and Janus particles 15,25,34,45 discussed in the literature. The reported colloidal building blocks exhibit either a purely so (organic), 14 purely hard (inorganic), or hybrid (so/hard) character.…”

Planet–Satellite Nanostructures Based on Block Copolymer‐Surfactant Nanoparticles Surface‐Decorated with Gold and Silver: A New Strategy for Interfacial Catalysis

“…Among the different types of conjugates investigated, hybrid nanostructures based on Ag and Au NPs and polymer‐based nanomaterials have received great attention. In these conjugates, the metal NPs can be located into the core, along the whole structure, or at the outer surface of the polymer‐based nanomaterials, in the last case generating planet–satellite nanostructures, in which the polymer‐based nanomaterial comprises the planet and the metal NPs, the satellites …”