Spontaneous, Solvent-Free, Polymer-Templated, Solid–Solid Transformation of Thin Metal Films into Nanoparticles

Abstract

Metal nanoparticles have unusual optical, electronic, sensing, recognition, catalytic, and therapeutic properties. They are expected to form the basis of many of the technological and biological innovations of this century. A prerequisite for future applications using nanoparticles as functional entities is control of the shape, size, and homogeneity of these nanoparticles and of their interparticle spacing and arrangement on surfaces, between electrodes, or in devices. Here, we demonstrate that thin films of gold, silver, and copper sputter-deposited onto the surface of an organic polymer poly[[1,1':4',1″-terphenyl]-4,4″-diyl(2-bromo-1-carboxyethylidene)] (PTBC) undergo spontaneous solid-solid transformation into nanoparticles. Furthermore, we show that, by varying the thickness of the films, the volume-to-surface ratio of the polymer substrate, and the amount of plasticizer, it is possible to control the rate of transformation and the morphology of the nanoparticles formed. PTBC containing Au nanoparticles was found to enhance the cell adhesion and proliferation. To the best of our knowledge, our findings constitute the first experimental evidence of spontaneous, room-temperature, solid-solid transformation of metal films sputtered onto the surface of an organic polymeric substrate into nanoparticles (crystals).

In Situ Self-Assembly of Ultrastable Gold Nanoparticles on Polyvinyl Alcohol Nanofibrous Mats for Use as Highly Reusable Catalysts

“…Metal nanoparticles (NPs) have been the subject of increasing interest because of their importance in the field of nanoscience. Gold NPs, in particular, are one of the most widely studied NP systems because of their far-ranging potential applications, such as in catalysis, sensors, optical devices, energy, and biology. − However, colloidal Au NPs have high surface energy, and not only readily aggregate but also are difficult to retrieve and reuse in aqueous or nonaqueous media. Therefore, stabilization is essential to immobilize Au NPs and prevent their aggregation in most applications, particularly in catalysis.…”

Surface Functionalization and Escherichia coli Detection Using Surface-Enhanced Raman Spectroscopy Driven by Functional Organic Polymer/Gold Nanofilm-Based Microfluidic Chip

“…According to Hernández-Cruz et al, the Au film deposited on FOP material is transformed into nanoparticles over time, resulting in more extensive and more spaced nanoparticles daily [23]. Figures 3 and 4 show the simulation results of the 3D model described in Section 2.2 considering 6, 12, 18, and 24 days of post-deposition time.…”

“…From the wave optics module of COMSOL, the electromagnetic waves-frequency domain and the frequency domain were selected as the physical interface and study type, respectively. The size of the 3D model was varied according to the results reported by Hernández-Cruz et al for 5 nm post-deposited Au films [23]. They reported that the Au layer modifies its morphology very slowly (the process takes more than 20 days), and linear relationships of the width and spacing of the Au nanoclusters versus time were assumed [23].…”

“…The size of the 3D model was varied according to the results reported by Hernández-Cruz et al for 5 nm post-deposited Au films [23]. They reported that the Au layer modifies its morphology very slowly (the process takes more than 20 days), and linear relationships of the width and spacing of the Au nanoclusters versus time were assumed [23]. The layer ordering of the 3D model, from top to bottom, was as follows: air (1 µm thick), PMMA membrane (5 µm thick), FOP film (1 µm thick), Au film (5 nm thick), and water (1 µm thick).…”

A Nanosystem of Amphiphilic Oligopeptide-Drug Conjugate Actualizing Both αvβ3 Targeting and Reduction-Triggered Release for Maytansinoid

“…Nanoparticulate-based drug delivery systems (nano-DDS) have experienced tremendous development and are expected to bring radical solutions to the limitations of conventional chemotherapy 4 , because they improve the tumor accumulation and safety of chemodrugs 5 . Nanomedicines 6 - 8 including liposomes 9 , water-soluble polymers 10 , vesicles 11 , dendrimers 12 , polymer nanoparticles or micelles 13 , 14 , inorganic nanoparticles 15 , and some hybrid organic-inorganic nanosystems 16 , have been studied extensively for this purpose. However, the general outcome of antitumor nanomedicines after past few decades seems far from satisfactory, and one of the reasons seems the inferior delivery efficiency 17 .…”