Gold Nanoparticles in DNA‐Based Multilayer Films: Synthesis, Size Control, and Influence of the Multilayer Structure on Catalytic Properties

Abstract

A method to prepare DNA‐based multilayered microcapsules as a host matrix for synthesizing ultrasmall gold nanoparticles of 2–4 nm in size is presented. Utilizing the intrinsic affinity of DNA for transition metal ions, ionic gold was first efficiently concentrated inside the DNA‐based multilayers assembled on a CaCO3 sacrificial template. Further reduction of ionic gold inside the multilayers resulted in the formation of high‐density, well‐dispersed 2–4 nm gold nanoparticles distributed evenly and exclusively inside the polyelectrolyte multilayers. Metallized multilayers containing ultrafine gold nanoparticles showed a good performance in catalytic reduction of nitroaromatic compounds and the catalytic activity of gold nanoparticles was enhanced with a decrease of host multilayer thickness. The influence of the multilayer structure and composition on size and catalytic activity of gold nanoparticles is discussed.

DNA motifs hydrogel microparticles as gold nanocatalyst support material

“…The adsorption of 4-nitrophenol onto the Au NP catalyst surface is likely to be the rate-determining step of the reduction reaction, since the induction period is significantly prolonged when the Au NP surface is coated with ligands 45 or surfactants 46 . The access of 4nitrophenol to Au NP catalysts supported on polymers such as our system is hindered by the tightly crosslinked structure and entanglement of the polymer chains [47][48][49] ; however, the porous polymer supports 50,51 The rate constants k at 293 K obtained from the pseudo-first-order plots of the Au NPsupported Y-18, Y-28, and Y-39, were 8.9 × 10 −2 s −1 , 6.3 × 10 −2 s −1 , and 2.2 × 10 −2 s −1 , respectively.…”

Recent Advances in Hybrid Biomimetic Polymer-Based Films: from Assembly to Applications

“…Besides gene delivery and sensing of nucleic acid, PE-DNA film has been reported as a catalytic matrix for the synthesis of metal NPs. Due to the intrinsic affinity of DNA for transition metal ions, ionic gold has been efficiently reduced inside the DNA-based multilayer, e.g., PSSNa/poly(allylamine hydrochloride) (PAH)/DNA [36] or poly(diallyldimethylammonium chloride) (PDADMAC)-DNA [49]. In the latter case, catalytically active AuNPs, sized between 2 and 4 nm, have been uniformly distributed within the PE membrane, which, at the same time, has acted as a scaffold matrix locally immobilizing the NPs and thus preventing their aggregation.…”

“…For each system, the assembly approach has been presented, in particular layer-by-layer, bottom-up, and top-down (grafting "from" and grafting "to", respectively), Langmuir-Blodgett and Langmuir-Schaefer methods, and some of the analytical methods commonly utilized for characterization of such films have been mentioned. The review has further exemplified their distinct properties and the properties-related applications for the development of biosensors [17][18][19][20][21][22][23][24][25][26][27][28][29][30], drug delivery platforms [16,[31][32][33][34][35][36][37][38][39][40][41][42][43], cell culture platforms [44,45], biomimicry [46,47], bioelectronic devices, e.g., [48], catalytic matrices [49][50][51], biomimetic lubricants First, we have described biomimetic hybrids based on polyelectrolytes and diverse biomacromolecules, natural polymers, and nanoparticles, followed by the presentation of solid-supported films based on polymer brushes produced either via bottom-up or top-down approach. Next, polymer-lipid tethered and cushioned composite films have been discussed with respect to their composition and properties.…”

“…For each system, the assembly approach has been presented, in particular layer-by-layer, bottom-up, and top-down (grafting "from" and grafting "to", respectively), Langmuir-Blodgett and Langmuir-Schaefer methods, and some of the analytical methods commonly utilized for characterization of such films have been mentioned. The review has further exemplified their distinct properties and the properties-related applications for the development of biosensors [17][18][19][20][21][22][23][24][25][26][27][28][29][30], drug delivery platforms [16,[31][32][33][34][35][36][37][38][39][40][41][42][43], cell culture platforms [44,45], biomimicry [46,47], bioelectronic Polymers 2020, 12, 1003 3 of 52 devices, e.g., [48], catalytic matrices [49][50][51], biomimetic lubricants [52,53], or anti-biofouling coatings, e.g., [14,54], among others, illustrated with the most interesting chosen examples based on the recent reports. Due to the aforementioned, this work has presented, in a comprehensive manner, multiple approaches to the synthesis, processing, and applications of hybrid biomimetic films based on various polymer species, which, in our opinion, would be interesting for both the specialists in the ...…”