Статті в журналах: "Gold/silicon catalysis"

1

Coulthard, I., S. Degen, Y. J. Zhu, and T. K. Sham. "Gold nanoclusters reductively deposited on porous silicon: morphology and electronic structures." Canadian Journal of Chemistry 76, no. 11 (November 1, 1998): 1707–16. http://dx.doi.org/10.1139/v98-146.

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Utilizing porous silicon as a reducing agent and a substrate, gold complex ions [AuCl4]- were reduced from aqueous solution to produce nanoparticles of gold upon the surface of porous silicon. Scanning electron microscopy (SEM) was utilized to study the morphology of the porous silicon layers and the deposits of gold nanoparticles. It is found that preparation conditions have a profound effect on the morphology of the deposits, especially on porous silicon prepared from a p-type wafer. The gold nanoparticles, varying from micrometric aggregates of clusters of the order of 10 nm, to a distribution of nearly spherical clusters of the order of 10 nm, to strings of ~10 nm were observed and compared to bulk gold metal using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS). These techniques confirm and complement the SEM findings. The potential for this reductive deposition technique is noted.Key words: gold nanostructures, reductive deposition, porous silicon, morphology, X-ray spectroscopy.

2

Hashmi, A. Stephen K., Tanuja Dondeti Ramamurthi, Matthew H. Todd, Althea S. K. Tsang, and Katharina Graf. "Gold-Catalysis: Reactions of Organogold Compounds with Electrophiles." Australian Journal of Chemistry 63, no. 12 (2010): 1619. http://dx.doi.org/10.1071/ch10342.

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Different arylgold(i), one alkynylgold(i), and one vinylgold(i) triphenylphosphane complexes were subjected to electrophilic halogenation reagents. With N-chlorosuccinimid, N-bromosuccinimid, and N-iodosuccinimid as well as the Barluenga reagent, selectively halogenated compounds were obtained. Trifluoroacetic acid, as a source of protons, leads to a clean protodeauration. With N-fluorobenzenesulfonimide or Selectfluor, exclusively a homocoupling was observed. For the precursor of the vinylgold(i) complex, a similar oxidative coupling could be induced by gold(iii) chloride. Reactions with silicon or tin electrophiles failed.

3

Süzer, Sefik, and Ömer Dag. "Reductive deposition of Au3+(aq) on oxidized silicon surfaces." Canadian Journal of Chemistry 78, no. 4 (April 1, 2000): 516–19. http://dx.doi.org/10.1139/v00-039.

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X-ray photoelectron spectroscopy (XPS) is used to determine the oxidation state of gold deposited from an aqueous solution of AuCl4- on to various oxidized surfaces of silicon. Although the observed Au4f signal decreased with the thickness of the oxide layer, the oxidation state of Au was determined as 0 for all the samples analyzed. From the angular dependence of the Si2p and Au4f signals it was determined that Au is deposited on top of the oxidized surfaces of metallic silicon. It is postulated that from an aqueous solution of AuCl4-, gold would deposit in its zerovalent form on to any surface due to its large and positive electrochemical reduction potential (ε°red(Au3+ /Au) = +1.50 V) and the substrate plays a role only in providing active deposition sites. To further support the proposal, it is shown that the same process takes place even in inert and hydrophobic polypropylene substrates. Similarly, it is also shown that more gold deposits if the surface of the polypropylene is made less hydrophobic (but probably more active) via the industrially used corona discharge treatment.Key words: XPS, gold, electroless deposition, oxidized silicon surface.

4

Zhang, Peng, Andy Yuan-Chi Chu, Tsun-Kong Sham, Yun Yao, and Shuit-Tong Lee. "Chemical synthesis and structural studies of thiol-capped gold nanoparticles." Canadian Journal of Chemistry 87, no. 1 (January 1, 2009): 335–40. http://dx.doi.org/10.1139/v08-135.

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We report the chemical synthesis and structural studies of thiol-capped Au nanoparticles (NPs) using extended X-ray absorption fine structures (EXAFS) and high-resolution transmission electron microscopy (HRTEM). Synthesis of Au NPs was conducted in one case in a toluene/water two-phase system using alkanethiols with varied hydrocarbon chain length (C6, C12, and C18), resulting in NPs of sizes ranging from 1.6 nm to 5.4 nm. Au L3-edge EXAFS reveals a systematical trend of the local structure of Au in the NPs when the Au/S ratio and chain-length of thiols are varied. In another synthesis, thiol-capped Au NPs were prepared on the surface of silicon nanowires, which act as both substrates and reducing agents. HRTEM reveals that not only spherical particles but also very small quasi-1D nanostructures of Au were formed. The formation and structure of these Au NPs was discussed in terms of ligand and template effect associated with the silicon nanowire substrates.Key words: thiol-capped Au nanoparticles, EXAFS, silicon nanowires, electroless deposition, quasi-1D Au nanostructures.

5

Lewis, James, and David J. Smith. "Structural rearrangements in small gold particles." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 640–41. http://dx.doi.org/10.1017/s0424820100155177.

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A knowledge of the structure of small metal particles is fundamental to understanding their role in heterogeneous catalysis. It is therefore of much topical interest that structural rearrangements have been found to take place as a result of intense electron irradiation within the electron microscope. Initial observations were of gold particles on supports of carbon and silica-covered silicon, but further studies confirmed that qualitatively similar behaviour also took place for particles of Pt, Ru and Rh. Some of the factors which influence the motion have been noted, including the particle size, the nature of the substrate and, obviously, the current density of the electron beam. Considerable debate has been generated by these observations. It has been suggested, for example, that the structural fluctuations should be dampened by an electrically conducting substrate which would prevent the particles from becoming charged. It was also proposed that the “quasimelting” of gold particles was triggered by Auger decay, in effect heating the particles electronically rather than thermally. The energetics of these fluctuations have also been considered.In this paper, we report our initial efforts to quantify some of the experimental factors involved in this quasimelting process. Three sets of samples were prepared: one was a normal holey carbon support film, the second was a holey silicon support film, and the third was a carbon film upon which graphitised carbon had been deposited.

6

Pastre, Aymeric, Odile Cristini, Alexandre Boe, Katarzyna Raulin, Bertrand Grimbert, Fernand Chassagneux, Nathalie Rolland, and Remy Bernard. "Porous Gold Films Fabricated by Wet-Chemistry Processes." Journal of Nanomaterials 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/3536153.

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Porous gold films presented in this paper are formed by combining gold electroless deposition and polystyrene beads templating methods. This original approach allows the formation of conductive films (2 × 106 (Ω·cm)−1) with tailored and interconnected porosity. The porous gold film was deposited up to 1.2 μm on the silicon substrate without delamination. An original zirconia gel matrix containing gold nanoparticles deposited on the substrate acts both as an adhesion layer through the creation of covalent bonds and as a seed layer for the metallic gold film growth. Dip-coating parameters and gold electroless deposition kinetics have been optimized in order to create a three-dimensional network of 20 nm wide pores separated by 20 nm thick continuous gold layers. The resulting porous gold films were characterized by GIXRD, SEM, krypton adsorption-desorption, and 4-point probes method. The process is adaptable to different pore sizes and based on wet-chemistry. Consequently, the porous gold films presented in this paper can be used in a wide range of applications such as sensing, catalysis, optics, or electronics.

7

Liu, Yuelong, Merlin L. Bruening, David E. Bergbreiter, and Richard M. Crooks. "Multilayer Dendrimer–Polyanhydride Composite Films on Glass, Silicon, and Gold Wafers." Angewandte Chemie International Edition in English 36, no. 19 (October 17, 1997): 2114–16. http://dx.doi.org/10.1002/anie.199721141.

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8

Platnich, Casey M., Abhinandan Banerjee, Vinayaraj Ozhukil Kollath, Kunal Karan, and Simon Trudel. "Thiol-ene click microcontact printing of gold nanoparticles onto silicon surfaces." Canadian Journal of Chemistry 96, no. 2 (February 2018): 190–95. http://dx.doi.org/10.1139/cjc-2017-0321.

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We report a novel process to selectively pattern nanomaterials, specifically gold nanoparticles, onto a silicon surface through “click” chemistry, to consistently and efficiently join together small units through a quick and simple reaction. We employed the UV-initiated thiol-ene reaction, which is used in tandem with microcontact printing. Dithiol-capped nanoparticles were used as a printing ink and were grafted onto ene-terminated Si(100) wafers by pressing a nanoparticle-impregnated poly(dimethylsiloxane) stamp, while irradiating with ultraviolet light to activate a radical initiator. The resulting structures were characterized using scanning electron microscopy and atomic force microscopy.

9

Shtepliuk, Ivan, Ivan G. Ivanov, Nikolaos Pliatsikas, Tihomir Iakimov, Samuel Lara-Avila, Kyung Ho Kim, Nabiha Ben Sedrine, Sergey E. Kubatkin, Kostas Sarakinos, and Rositsa Yakimova. "Clustering and Morphology Evolution of Gold on Nanostructured Surfaces of Silicon Carbide: Implications for Catalysis and Sensing." ACS Applied Nano Materials 4, no. 2 (January 14, 2021): 1282–93. http://dx.doi.org/10.1021/acsanm.0c02867.

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10

Cai, Jiandong, Chen Li, Na Kong, Yi Lu, Geyu Lin, Xinyan Wang, Yuan Yao, Ian Manners, and Huibin Qiu. "Tailored multifunctional micellar brushes via crystallization-driven growth from a surface." Science 366, no. 6469 (November 28, 2019): 1095–98. http://dx.doi.org/10.1126/science.aax9075.

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The creation of nanostructures with precise chemistries on material surfaces is of importance in a wide variety of areas such as lithography, superhydrophobicity, and cell adhesion. We describe a platform for surface functionalization that involves the fabrication of cylindrical micellar brushes on a silicon wafer through seeded growth of crystallizable block copolymers at the termini of immobilized, surface-confined crystallite seeds. The density, length, and coronal chemistry of the micellar brushes can be precisely tuned, and post-growth decoration with nanoparticles enables applications in catalysis and antibacterial surface modification. The micellar brushes can also be grown on ultrathin two-dimensional materials such as graphene oxide nanosheets and further assembled into a membrane for the separation of oil-in-water emulsions and gold nanoparticles.

11

Abulikemu, Mutalifu, Eman Husni Da'as, Hanna Haverinen, Dongkyu Cha, Mohammad Azad Malik, and Ghassan Elie Jabbour. "In Situ Synthesis of Self-Assembled Gold Nanoparticles on Glass or Silicon Substrates through Reactive Inkjet Printing." Angewandte Chemie International Edition 53, no. 2 (December 18, 2013): 420–23. http://dx.doi.org/10.1002/anie.201308429.

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12

Nishioka, Kensuke, Susumu Horita, Keisuke Ohdaira, and Hideki Matsumura. "Antireflection subwavelength structure of silicon surface formed by wet process using catalysis of single nano-sized gold particle." Solar Energy Materials and Solar Cells 92, no. 8 (August 2008): 919–22. http://dx.doi.org/10.1016/j.solmat.2008.02.017.

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13

Suárez-Pantiga, Samuel, and José M. González. "Electrophilic activation of unsaturated systems: Applications to selective organic synthesis." Pure and Applied Chemistry 85, no. 4 (March 13, 2013): 721–39. http://dx.doi.org/10.1351/pac-con-12-10-24.

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Selected examples from previous work on iodonium-triggered approaches for the functionalization of unsaturated systems, which summarize innovative transformations, are presented. This section is mostly focused on C–C bond-forming processes from alkynes that are directly bonded to relevant heteroatoms, such as iodine, silicon, or sulfur. Besides, recent advances related to iodonium-promoted C–H functionalization reactions are briefly outlined. A second section shows representative examples of our current research activity on electrophilic reactions aimed at the activation of unsaturated systems, which now are built upon the potential offered by the so-called carbophilic catalysis. More specifically, a new catalytic cyclopentannulation sequence from N-tosylimines and propargyl tosylates and novel C–H functionalization processes from related tosylates are studied. Likewise, representative examples for the intermolecular Au(I)-catalyzed [2 + 2] cycloaddition reaction of sulfonylallenamides with activated alkenes are given, including the first enantioselective reaction of this type, which is also among the first examples of an intermolecular asymmetric gold-catalyzed reaction. The discussion of the reported iodonium and gold chemistry emphasizes a search for new intermolecular processes, although intramolecular reactions are also pursued and developed.

14

González, Jairo, Darío Allegue, Sergio Fernández, Miguel A. Rodríguez, Javier Santamaría, and Alfredo Ballesteros. "Divergent Gold‐Catalyzed Rearrangement of 1‐Alkenyl‐2‐alkynylcyclopropanes: Enyne Transformation Controlled by a Silicon Moiety." Advanced Synthesis & Catalysis 362, no. 18 (August 7, 2020): 3912–18. http://dx.doi.org/10.1002/adsc.202000521.

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15

Stolle, Heike Lisa Kerstin Stephanie, Andrea Csáki, Jan Dellith, and Wolfgang Fritzsche. "Modification of Surface Bond Au Nanospheres by Chemically and Plasmonically Induced Pd Deposition." Nanomaterials 11, no. 1 (January 18, 2021): 245. http://dx.doi.org/10.3390/nano11010245.

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In this work we investigated methods of modifying gold nanospheres bound to a silicon surface by depositing palladium onto the surfaces of single nanoparticles. Bimetallic Au-Pd nanoparticles can thus be gained for use in catalysis or sensor technology. For Pd deposition, two methods were chosen. The first method was the reduction of palladium acetate by ascorbic acid, in which the amounts of palladium acetate and ascorbic acid were varied. In the second method we utilized light-induced metal deposition by making use of the plasmonic effect. Through this method, the surface bond nanoparticles were irradiated with light of wavelengths capable of inducing plasmon resonance. The generation of hot electrons on the particle surface then reduced the palladium acetate in the vicinity of the gold nanoparticle, resulting in palladium-covered gold nanospheres. In our studies we demonstrated the effect of both enhancement methods by monitoring the particle heights over enhancement time by atomic force microscopy (AFM), and investigated the influence of ascorbic acid/Pd acetate concentration as well as the impact of the irradiated wavelengths on the enhancement effect. It could thus be proven that both methods were valid for obtaining a deposition of Pd on the surface of the gold nanoparticles. Deposition of Pd on the gold particles using the light-assisted method could be observed, indicating the impact of the plasmonic effect and hot electron for Pd acetate reduction on the gold particle surface. In the case of the reduction method with ascorbic acid, in addition to Pd deposition on the gold nanoparticle surface, larger pure Pd particles and extended clusters were also generated. The reduction with ascorbic acid however led to a considerably thicker Pd layer of up to 54 nm in comparison to up to 11 nm for the light-induced metal deposition with light resonant to the particle absorption wavelength. Likewise, it could be demonstrated that light of non-resonant wavelengths was not capable of initiating Pd deposition, since a growth of only 1.6 nm (maximum) was observed for the Pd layer.

16

Nyembe, Sanele, Gebhu Ndlovu, Poslet Shumbula, Richard Harris, Nosipho Moloto, and Lucky Sikhwivhilu. "Laser Assisted Catalytic Growth of Silicon Nanowires Using Gold and Nickel Catalysts." Journal of Nanoscience and Nanotechnology 21, no. 10 (October 1, 2021): 5260–65. http://dx.doi.org/10.1166/jnn.2021.19448.

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Laser assisted synthesis of silicon nanowires (SiNWs) was successfully achieved through the use of gold and nickel as catalysts. The diameter of the resulting SiNWs was found to be dependent on that of the catalyst in the case of gold catalyst. The gold catalysed silicon nanowires were unevenly curved and branched owing to the high kinetic energy possessed by gold nanoparticles (AuNPs) at relatively high processing temperature. The use of nickel as catalyst resulted in the formation of several SiNWs on a single nickel catalyst crystallite due to interconnection of the nickel metal crystallites at processing temperature. The morphology of SiNWs catalysed by both nickel and gold was controlled by optimising the laser energy during ablation.

17

Moreau, François, and Geoffrey C. Bond. "Oxidative dehydrogenation of 1-butene catalysed by silica-supported gold and silicon carbide, alone and in admixture." Catalysis Communications 8, no. 9 (September 2007): 1403–5. http://dx.doi.org/10.1016/j.catcom.2006.12.003.

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18

Ikramova, Saltanat B., Zhandos N. Utegulov, Kadyrjan K. Dikhanbayev, Abduzhappar E. Gaipov, Renata R. Nemkayeva, Valery G. Yakunin, Vladimir P. Savinov, and Victor Yu Timoshenko. "Surface-Enhanced Raman Scattering from Dye Molecules in Silicon Nanowire Structures Decorated by Gold Nanoparticles." International Journal of Molecular Sciences 23, no. 5 (February 26, 2022): 2590. http://dx.doi.org/10.3390/ijms23052590.

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Silicon nanowires (SiNWs) prepared by metal-assisted chemical etching of crystalline silicon wafers followed by deposition of plasmonic gold (Au) nanoparticles (NPs) were explored as templates for surface-enhanced Raman scattering (SERS) from probe molecules of Methylene blue and Rhodamine B. The filling factor by pores (porosity) of SiNW arrays was found to control the SERS efficiency, and the maximal enhancement was observed for the samples with porosity of 55%, which corresponded to dense arrays of SiNWs. The obtained results are discussed in terms of the electromagnetic enhancement of SERS related to the localized surface plasmon resonances in Au-NPs on SiNW’s surfaces accompanied with light scattering in the SiNW arrays. The observed SERS effect combined with the high stability of Au-NPs, scalability, and relatively simple preparation method are promising for the application of SiNW:Au-NP hybrid nanostructures as templates in molecular sensorics.

19

Peiris, Chandramalika R., Yan B. Vogel, Anton P. Le Brun, Albert C. Aragonès, Michelle L. Coote, Ismael Díez-Pérez, Simone Ciampi, and Nadim Darwish. "Metal–Single-Molecule–Semiconductor Junctions Formed by a Radical Reaction Bridging Gold and Silicon Electrodes." Journal of the American Chemical Society 141, no. 37 (August 27, 2019): 14788–97. http://dx.doi.org/10.1021/jacs.9b07125.

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20

Svirshchevskaya, Elena V., Nina V. Sharonova, Rimma A. Poltavtseva, Mariya V. Konovalova, Anton E. Efimov, Anton A. Popov, Svetlana V. Sizova, Daria O. Solovyeva, Ivan V. Bogdanov, and Vladimir A. Oleinikov. "Silicon–Gold Nanoparticles Affect Wharton’s Jelly Phenotype and Secretome during Tri-Lineage Differentiation." International Journal of Molecular Sciences 23, no. 4 (February 15, 2022): 2134. http://dx.doi.org/10.3390/ijms23042134.

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Multiple studies have demonstrated that various nanoparticles (NPs) stimulate osteogenic differentiation of mesenchymal stem cells (MSCs) and inhibit adipogenic ones. The mechanisms of these effects are not determined. The aim of this paper was to estimate Wharton’s Jelly MSCs phenotype and humoral factor production during tri-lineage differentiation per se and in the presence of silicon–gold NPs. Silicon (SiNPs), gold (AuNPs), and 10% Au-doped Si nanoparticles (SiAuNPs) were synthesized by laser ablation, characterized, and studied in MSC cultures before and during differentiation. Humoral factor production (n = 41) was analyzed by Luminex technology. NPs were nontoxic, did not induce ROS production, and stimulated G-CSF, GM-CSF, VEGF, CXCL1 (GRO) production in four day MSC cultures. During MSC differentiation, all NPs stimulated CD13 and CD90 expression in osteogenic cultures. MSC differentiation resulted in a decrease in multiple humoral factor production to day 14 of incubation. NPs did not significantly affect the production in chondrogenic cultures and stimulated it in both osteogenic and adipogenic ones. The major difference in the protein production between osteogenic and adipogenic MSC cultures in the presence of NPs was VEGF level, which was unaffected in osteogenic cells and 4–9 times increased in adipogenic ones. The effects of NPs decreased in a row AuNPs > SiAuNPs > SiNPs. Taken collectively, high expression of CD13 and CD90 by MSCs and critical level of VEGF production can, at least, partially explain the stimulatory effect of NPs on MSC osteogenic differentiation.

21

Ren, Yi, Thomas Linder, and Thomas Baumgartner. "Synthesis and properties of ladder-type 1,4-dihydro-1,4-phosphasilins." Canadian Journal of Chemistry 87, no. 9 (September 2009): 1222–29. http://dx.doi.org/10.1139/v09-108.

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The synthesis and advanced characterization of a series of extended dithieno[2,3-b:3′,2′-e][1,4-dihydro-1,4]phosphasilins is reported, and their suitability as new building blocks for organic electronics is evaluated. Synthesis of basic, as well as benzo-extended dithienophosphasilins, can be achieved using appropriate 2,3-dibromothiophene precursors in a two-step protocol introducing the silicon and phosphorus centers subsequently. Both ladder-type materials show the typical reactivity of trivalent phosphorus species and can quantitatively be converted into the corresponding oxides or gold complexes, the latter exemplified with the basic dithienophosphasilin. Their optoelectronic properties were found to be inferior to those of related dithieno[3,2-b:2′,3′-d]phospholes, indicating a disruption of the π-conjugation in the molecular scaffold. X-ray crystallographic studies revealed that the molecular scaffold is planar in the oxidized benzo-extended material, whereas the basic dithieno materials show some small deviation from planarity. Density functional theory calculations suggest all materials to be planar, with the exception of the benzo-extended trivalent phosphasilin. This structure–property study illustrates that the disruption of the π-conjugation in the molecular scaffold of the extended phosphasilins is exclusively due to the presence of the silicon center and its electronic effects, rather than structural features.

22

Flimelová, Miroslava, Yury V. Ryabchikov, Jan Behrends, and Nadezhda M. Bulgakova. "Environmentally Friendly Improvement of Plasmonic Nanostructure Functionality towards Magnetic Resonance Applications." Nanomaterials 13, no. 4 (February 17, 2023): 764. http://dx.doi.org/10.3390/nano13040764.

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Plasmonic nanostructures have attracted a broad research interest due to their application perspectives in various fields such as biosensing, catalysis, photovoltaics, and biomedicine. Their synthesis by pulsed laser ablation in pure water enables eliminating various side effects originating from chemical contamination. Another advantage of pulsed laser ablation in liquids (PLAL) is the possibility to controllably produce plasmonic nanoparticles (NPs) in combination with other plasmonic or magnetic materials, thus enhancing their functionality. However, the PLAL technique is still challenging in respect of merging metallic and semiconductor specific features in nanosized objects that could significantly broaden application areas of plasmonic nanostructures. In this work, we performed synthesis of hybrid AuSi NPs with novel modalities by ultrashort laser ablation of bulk gold in water containing silicon NPs. The Au/Si atomic ratio in the nanohybrids was finely varied from 0.5 to 3.5 when changing the initial Si NPs concentration in water from 70 µg/mL to 10 µg/mL, respectively, without requiring any complex chemical procedures. It has been found that the laser-fluence-insensitive silicon content depends on the mass of nanohybrids. A high concentration of paramagnetic defects (2.2·× 1018 spin/g) in polycrystalline plasmonic NPs has been achieved. Our findings can open further prospects for plasmonic nanostructures as contrast agents in optical and magnetic resonance imaging techniques, biosensing, and cancer theranostics.

23

Seregin, Ilya V., and Vladimir Gevorgyan. "Gold-Catalyzed 1,2-Migration of Silicon, Tin, and Germanium en Route to C-2 Substituted Fused Pyrrole-Containing Heterocycles." Journal of the American Chemical Society 128, no. 37 (September 2006): 12050–51. http://dx.doi.org/10.1021/ja063278l.

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24

Abulikemu, Mutalifu, Eman Husni Da'as, Hanna Haverinen, Dongkyu Cha, Mohammad Azad Malik, and Ghassan Elie Jabbour. "Inside Back Cover: In Situ Synthesis of Self-Assembled Gold Nanoparticles on Glass or Silicon Substrates through Reactive Inkjet Printing (Angew. Chem. Int. Ed. 2/2014)." Angewandte Chemie International Edition 53, no. 2 (December 18, 2013): 599. http://dx.doi.org/10.1002/anie.201310429.

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25

Islam, Mohammad, Zineb Matouk, Nadir Ouldhamadouche, Jean-Jacques Pireaux, and Amine Achour. "Plasma Treatment of Polystyrene Films—Effect on Wettability and Surface Interactions with Au Nanoparticles." Plasma 6, no. 2 (May 29, 2023): 322–33. http://dx.doi.org/10.3390/plasma6020022.

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Polystyrene (PS)/Gold (Au) is used for a wide range of applications, including composite nanofibers, catalysis, organic memory devices, and biosensing. In this work, PS films were deposited on silicon substrates via a spin coating technique followed by treatment with argon (Ar) plasma admixed with ammonia (NH3), oxygen (O2), or tetrafluoroethane (C2H2F4). X-Ray photoelectron spectroscopy (XPS) analysis revealed modified surface chemistry for Ar/O2, Ar/NH3, or Ar/C2H2F4 plasma treatment through the incorporation of oxygen, nitrogen, or fluorine groups, respectively. Size-controlled magnetron sputter deposition of Au nanoparticles (NP) onto these plasma-treated PS films was investigated via XPS and AFM techniques. The interaction of the Au NPs, as probed from the XPS and AFM measurements, is discussed by referring to changes in surface chemistry and morphology of the PS after plasma treatment. The results demonstrate the effect of surface chemistry on the interaction of Au NPs with polymer support having different surface functionalities. The XPS results show that significant oxygen surface incorporation resulted from oxygen-containing species in the plasma itself. The surface concentration of O increased from 0.4% for the pristine PS to 4.5 at%, 35.4 at%, and 45.6 at% for the Ar/C2H4F4, Ar/NH3, and Ar/O2, respectively. The water contact angle (WCA) values were noticed to decrease from 98° for the untreated PS to 95°, 37°, and 15° for Ar/C2H2F4, Ar/NH3, and Ar/O2 plasma-modified PS samples, respectively. AFM results demonstrate that surface treatment was also accompanied by surface morphology change. Small Au islands are well dispersed and cover the surface, thus forming a homogeneous, isotropic structure. The reported results are important for exploiting Au NPs use in catalysis and sensing applications.

26

Nanev, Christo N., Emmanuel Saridakis, Lata Govada, and Naomi E. Chayen. "Protein Crystals Nucleated and Grown by Means of Porous Materials Display Improved X-ray Diffraction Quality." International Journal of Molecular Sciences 23, no. 18 (September 14, 2022): 10676. http://dx.doi.org/10.3390/ijms231810676.

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Well-diffracting protein crystals are indispensable for X-ray diffraction analysis, which is still the most powerful method for structure-function studies of biomolecules. A promising approach to growing such crystals is the use of porous nucleation-inducing materials. However, while protein crystal nucleation in pores has been thoroughly considered, little attention has been paid to the subsequent growth of crystals. Although the nucleation stage is decisive, it is the subsequent growth of crystals outside the pore that determines their diffraction quality. The molecular-scale mechanism of growth of protein crystals in and outside pores is theoretically considered. Due to the low degree of metastability, the crystals that emerge from the pores grow slowly, which is a prerequisite for better diffraction. This expectation has been corroborated by experiments carried out with several types of porous material, such as bioglass (“Naomi’s Nucleant”), buckypaper, porous gold and porous silicon. Protein crystals grown with the aid of bioglass and buckypaper yield significantly better diffraction quality compared with crystals grown conventionally. In all cases, visually superior crystals are usually obtained. Our theoretical conclusion is that heterogeneous nucleation of a crystal outside the pore is an exceptional case. Rather, the protein crystals nucleating inside the pores continue growing outside them.

27

Lo Faro, Maria Josè, Ileana Ielo, Dario Morganti, Antonio Alessio Leonardi, Sabrina Conoci, Barbara Fazio, Giovanna De Luca, and Alessia Irrera. "Alkoxysilane-Mediated Decoration of Si Nanowires Vertical Arrays with Au Nanoparticles as Improved SERS-Active Platforms." International Journal of Molecular Sciences 24, no. 23 (November 24, 2023): 16685. http://dx.doi.org/10.3390/ijms242316685.

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The search for improved transducers to fabricate better-performing (bio)sensors is a challenging but rewarding endeavor aiming to better diagnose and treat diseases. In this paper, we report on the decoration of a dense vertical array of ultrathin silicon nanowires (Si NWs), produced by metal-assisted chemical etching, with 20 nm gold nanoparticles (Au NPs) for surface-enhanced Raman scattering (SERS) applications. To optimize the production of a uniform 3D SERS active platform, we tested different Si NW surface functionalizations with various alkoxysilanes before Au decoration. Scanning electron microscopy investigations confirm that Au NPs decorate both bare and (3-glycidiloxypropyl)trimethoxysilane (GPTMS)-modified Si NWs with a high surface coverage uniformity. The SERS response of the decorated NWs was probed using a model dye system (methylene blue; MB) at 633 and 785 nm excitation wavelengths. The GPTMS-modified NWs present the highest enhancements of 2.9 and 2.6 for the 450 cm−1 and 1625 cm−1 peaks under 785 nm excitation and of 10.8 and 5.3 for the 450 cm−1 and 1625 cm−1 peaks under 633 nm excitation. These results demonstrate the perspective role of Si NWs decorated with Au NPs as a low-cost 3D SERS platform.

28

Baratto, C., G. Sberveglieri, E. Comini, G. Faglia, G. Benussi, V. La Ferrara, L. Quercia, et al. "Gold-catalysed porous silicon for NOx sensing." Sensors and Actuators B: Chemical 68, no. 1-3 (August 2000): 74–80. http://dx.doi.org/10.1016/s0925-4005(00)00464-0.

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29

Zhu, Renkang, and Zhifeng Ding. "Enhancing image quality of scanning electrochemical microscopy by improved probe fabrication and displacement." Canadian Journal of Chemistry 83, no. 10 (October 1, 2005): 1779–91. http://dx.doi.org/10.1139/v05-189.

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Scanning electrochemical microscopy (SECM) is a powerful tool for its wide applications in determining charge transfer kinetics, imaging chemical reactions and topography, as well as fabricating microstructures at various interfaces and (or) surfaces. Imaging applications, in particular, rely on the natures of SECM probes and the scanning systems to move them in the vicinity of interfaces. While progress has been made in new approaches to tip fabrication, there are few reports on the improvement of the tip positioning system to enhance SECM image quality. We have recently built an advanced SECM setup using a closed-loop scanning system and improved probe fabrication and characterization procedures. Here we will describe this development, as well as the application of these techniques to greatly improve the quality of SECM images. Video micrograph, cyclic voltammograms, and SECM approach curves (current vs. tipsubstrate distance) were chosen to characterize probe quality and to determine the ratio of electrode diameter to glass sheath diameter. The SECM setup has a resolution and repeatability of 20 nm in three dimensions (x, y, and z) and can locate and relocate areas of interest precisely after a coarse image. Interdigitated electrode arrays of platinum and gold were first imaged. Image resolution revealed by sharpness of Pt band edges was enhanced by using a 2 µm diameter electrode. Pt or Au band height was found to be around 80200 nm by fitting the approach curves to the theoretical ones. Imaging conditions such as delay time for a large step size between two succeeding data points were optimized. To test its thermal and temporal stability, the system was then used to image letters, which were printed on a transparency with font bold Courier New and font size 2. Minor drifts were found during the image process up to the experimental length of 8 h and 45 min. Letter thickness was found to be 1.01.2 µm. A silicon substrate with an array of square pits spaced apart on 10 µm centers was finally imaged. Good quality images were obtained at various tipsubstrate distances even though the squares were just as small, if not smaller, than the tip. The samples were also imaged by AFM for comparison.Key words: scanning electrochemical microscopy, atomic force microscopy, microelectrode fabrication, closed-loop imaging, probe approach curve.

30

Müller, Martin, Jan Kočka, Hassan G. El Gohary, Jiri Stuchlik, Ha Stuchlikova, Karel Hruška, Bohuslav Rezek, Martin Ledinsky, and Antonin Fejfar. "Preparation and testing of silicon nanowires." Canadian Journal of Physics 92, no. 7/8 (July 2014): 819–21. http://dx.doi.org/10.1139/cjp-2013-0584.

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Here we present two ways of preparing lateral (in plane) silicon nanowires with the help of gold nanoislands catalysed plasma enhanced chemical vapour deposition. The role of the applied potential and eventual consecutive hydrogen plasma treatment is tested together with the thickness of the thin Au layer used for self-organised preparation of Au nanoislands.

31

Yao, Yuan, Fanghua Li, and Shuit-Tong Lee. "Oriented silicon nanowires on silicon substrates from oxide-assisted growth and gold catalysts." Chemical Physics Letters 406, no. 4-6 (May 2005): 381–85. http://dx.doi.org/10.1016/j.cplett.2005.03.027.

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32

Mohammed, Yasir Hussein, Samsudi Bin Sakrani, and Md Supar Rohani. "Tunable morphological evolution of in situ gold catalysts mediated silicon nanoneedles." Materials Science in Semiconductor Processing 50 (August 2016): 36–42. http://dx.doi.org/10.1016/j.mssp.2016.04.014.

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33

Ko, Tsung-Shine, Tien-Chang Lu, Chia-Pu Chu, Hao-Chung Kuo, and Shing-Chung Wang. "Thermally Evaporated In2O3 Nanoloquats with Tunable Broad-Band Emissions." Journal of Nanoscience and Nanotechnology 8, no. 9 (September 1, 2008): 4395–98. http://dx.doi.org/10.1166/jnn.2008.288.

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We describe synthesis of In2O3 nanoloquats grown by thermal evaporation under different oxygen flow rates and temperatures. Gold nanoparticles were used the catalysts and were dispersed on the silicon wafer to assist growth of In2O3 nanoloquats. The nanostructures of In2O3 nanoloquats were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The photoluminescence study reveals that In2O3 nanoloquats could emit different broad-band luminescence peaks in the range of 410∼620 nm by tuning different oxygen flow rates and temperatures. The wide tuning range in the emission peaks of In2O3 nanoloquats has potential in applications of white light illumination.

34

Wen, C. Y., M. C. Reuter, J. Bruley, J. Tersoff, S. Kodambaka, E. A. Stach, and F. M. Ross. "Formation of Compositionally Abrupt Axial Heterojunctions in Silicon-Germanium Nanowires." Science 326, no. 5957 (November 26, 2009): 1247–50. http://dx.doi.org/10.1126/science.1178606.

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We have formed compositionally abrupt interfaces in silicon-germanium (Si-Ge) and Si-SiGe heterostructure nanowires by using solid aluminum-gold alloy catalyst particles rather than the conventional liquid semiconductor–metal eutectic droplets. We demonstrated single interfaces that are defect-free and close to atomically abrupt, as well as quantum dots (i.e., Ge layers tens of atomic planes thick) embedded within Si wires. Real-time imaging of growth kinetics reveals that a low solubility of Si and Ge in the solid particle accounts for the interfacial abruptness. Solid catalysts that can form functional group IV nanowire-based structures may yield an extended range of electronic applications.

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Suzuki, Hiroshi, Hiroshi Araki, Masahiro Tosa, and Tetsuji Noda. "Formation of Silicon Nanowires by CVD Using Gold Catalysts at Low Temperatures." MATERIALS TRANSACTIONS 48, no. 8 (2007): 2202–6. http://dx.doi.org/10.2320/matertrans.mra2007059.

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36

Parlevliet, David, and Philip Jennings. "Thin film silicon nanowire photovoltaic devices produced with gold and tin catalysts." Journal of Nanoparticle Research 13, no. 10 (July 7, 2011): 4431–36. http://dx.doi.org/10.1007/s11051-011-0478-9.

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37

Matsumoto, Ayumu, Hikoyoshi Son, Makiho Eguchi, Keishi Iwamoto, Yuki Shimada, Kyohei Furukawa, and Shinji Yae. "General corrosion during metal-assisted etching of n-type silicon using different metal catalysts of silver, gold, and platinum." RSC Advances 10, no. 1 (2020): 253–59. http://dx.doi.org/10.1039/c9ra08728a.

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38

Naef, Noah U., and Stefan Seeger. "Silicone Nanofilament Support Layers in an Open-Channel System for the Fast Reduction of Para-Nitrophenol." Nanomaterials 11, no. 7 (June 24, 2021): 1663. http://dx.doi.org/10.3390/nano11071663.

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Chemical vapor phase deposition was used to create hydrophobic nanostructured surfaces on glass slides. Subsequently, hydrophilic channels were created by sputtering a metal catalyst on the channels while masking the outside. The surface tension gradient between the hydrophilic surface in the channels and the outside hydrophobicity formed the open-channel system. The reduction of para-nitrophenol (PNP) was studied on these devices. When compared to nanostructure-free reference systems, the created nanostructures, namely, silicone nanofilaments (SNFs) and nano-bagels, had superior catalytic performance (73% and 66% conversion to 55% at 0.5 µL/s flow rate using 20 nm platinum) and wall integrity; therefore, they could be readily used multiple times. The created nanostructures were stable under the reaction conditions, as observed with scanning electron microscopy. Transition electron microscopy studies of platinum-modified SNFs revealed that the catalyst is present as nanoparticles ranging up to 13 nm in size. By changing the target in the sputter coating unit, molybdenum, gold, nickel and copper were evaluated for their catalytic efficiency. The relative order was platinum < gold = molybdenum < nickel < copper. The decomposition of sodium borohydride (NaBH4) by platinum as a concurrent reaction to the para-nitrophenol reduction terminates the reaction before completion, despite a large excess of reducing agent. Gold had the same catalytic rate as molybdenum, while nickel was two times and copper about four times faster than gold. In all cases, there was a clear improvement in catalysis of silicone nanofilaments compared to a flat reference system.

39

Yang, Yaoyao, Jiali Zhang, Fangwei Zhang, and Shouwu Guo. "Preparation of AuNPs/GQDs/SiO2 Composite and Its Catalytic Performance in Oxidation of Veratryl Alcohol." Journal of Nanomaterials 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/4130569.

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Composites of gold nanoparticles and graphene quantum dots (AuNPs/GQDs) exhibit excellent dispersibility in aqueous solutions. Thus, it is difficult to separate them from wet reaction systems when they are used as catalysts. To resolve this issue, in this study, an AuNPs/GQDs composite was immobilized on silicon dioxide through the hydrothermal method, which involved the formation of an amide bond between the surface GQDs of the AuNPs/GQDs composite and the amino group of the silane. The as-synthesized AuNPs/GQDs/SiO2 composite was found to be suitable for use as a heterogeneous catalyst for the oxidation of veratryl alcohol in water and exhibited catalytic activity comparable to that of bare AuNPs/GQDs as well as better recyclability.

40

Shanshan, WANG, YIN Shujing, LIANG Haifeng, and HAN Jun. "Research on controllable preparation and optical properties of gold catalysed silicon nanowi res." Journal of Applied Optics 40, no. 5 (2019): 738–45. http://dx.doi.org/10.5768/jao201940.0501004.

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41

Ernst, Owen C., Felix Lange, David Uebel, Thomas Teubner, and Torsten Boeck. "Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth." Beilstein Journal of Nanotechnology 11 (September 9, 2020): 1371–80. http://dx.doi.org/10.3762/bjnano.11.121.

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The dewetting process is crucial for several applications in nanotechnology. Even though not all dewetting phenomena are fully understood yet, especially regarding metallic fluids, it is clear that the formation of nanometre-sized particles, droplets, and clusters as well as their movement are strongly linked to their wetting behaviour. For this reason, the thermodynamic stability of thin metal layers (0.1–100 nm) with respect to their free energy is examined here. The decisive factor for the theoretical considerations is the interfacial energy. In order to achieve a better understanding of the interfacial interactions, three different models for estimating the interfacial energy are presented here: (i) fully theoretical, (ii) empirical, and (iii) semi-empirical models. The formation of nanometre-sized gold particles on silicon and silicon oxide substrates is investigated in detail. In addition, the strengths and weaknesses of the three models are elucidated, the different substrates used are compared, and the possibility to further process the obtained particles as nanocatalysts is verified. The importance of a persistent thin communication wetting layer between the particles and its effects on particle size and number is also clarified here. In particular, the intrinsic reduction of the Laplace pressure of the system due to material re-evaporation and Ostwald ripening describes the theoretically predicted and experimentally obtained results. Thus, dewetting phenomena of thin metal layers can be used to manufacture nanostructured devices. From this point of view, the application of gold droplets as catalysts to grow germanium nanowires on different substrates is described.

42

Forrer, Nicolas, Arianna Nigro, Gerard Gadea, and Ilaria Zardo. "Influence of Different Carrier Gases, Temperature, and Partial Pressure on Growth Dynamics of Ge and Si Nanowires." Nanomaterials 13, no. 21 (October 30, 2023): 2879. http://dx.doi.org/10.3390/nano13212879.

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The broad and fascinating properties of nanowires and their synthesis have attracted great attention as building blocks for functional devices at the nanoscale. Silicon and germanium are highly interesting materials due to their compatibility with standard CMOS technology. Their combination provides optimal templates for quantum applications, for which nanowires need to be of high quality, with carefully designed dimensions, crystal phase, and orientation. In this work, we present a detailed study on the growth kinetics of silicon (length 0.1–1 μm, diameter 10–60 nm) and germanium (length 0.06–1 μm, diameter 10–500 nm) nanowires grown by chemical vapor deposition applying the vapour–liquid–solid growth method catalysed by gold. The effects of temperature, partial pressure of the precursor gas, and different carrier gases are analysed via scanning electron microscopy. Argon as carrier gas enhances the growth rate at higher temperatures (120 nm/min for Ar and 48 nm/min H2), while hydrogen enhances it at lower temperatures (35 nm/min for H2 and 22 nm/min for Ar) due to lower heat capacity. Both materials exhibit two growth regimes as a function of the temperature. The tapering rate is about ten times lower for silicon nanowires than for germanium ones. Finally, we identify the optimal conditions for nucleation in the nanowire growth process.

43

Włodarczyk, Jakub, Julia Krajewska, Łukasz Szeleszczuk, Patrycja Szałwińska, Agata Gurba, Szymon Lipiec, Przemysław Taciak, Remigiusz Szczepaniak, Izabela Mlynarczuk-Bialy, and Jakub Fichna. "A New Gold(III) Complex, TGS 703, Shows Potent Anti-Inflammatory Activity in Colitis via the Enzymatic and Non-Enzymatic Antioxidant System—An In Vitro, In Silico, and In Vivo Study." International Journal of Molecular Sciences 24, no. 8 (April 10, 2023): 7025. http://dx.doi.org/10.3390/ijms24087025.

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Inflammatory bowel diseases (IBD) and their main representatives, Crohn’s disease and ulcerative colitis, are worldwide health-care problems with constantly increasing frequency and still not fully understood pathogenesis. IBD treatment involves drugs such as corticosteroids, derivatives of 5-aminosalicylic acid, thiopurines, and others, with the goal to achieve and maintain remission of the disease. Nowadays, as our knowledge about IBD is continually growing, more specific and effective therapies at the molecular level are wanted. In our study, we tested novel gold complexes and their potential effect on inflammation and IBD in vitro, in silico, and in vivo. A series of new gold(III) complexes (TGS 404, 512, 701, 702, and 703) were designed and screened in the in vitro inflammation studies. In silico modeling was used to study the gold complexes’ structure vs. their activity and stability. Dextran sulphate sodium (DSS)-induced mouse model of colitis was employed to characterize the anti-inflammatory activity in vivo. Lipopolysaccharide (LPS)-stimulated RAW264.7 cell experiments proved the anti-inflammatory potential of all tested complexes. Selected on the bases of in vitro and in silico analyses, TGS 703 significantly alleviated inflammation in the DSS-induced mouse model of colitis, which was confirmed by a statistically significant decrease in the macro- and microscopic score of inflammation. The mechanism of action of TGS 703 was linked to the enzymatic and non-enzymatic antioxidant systems. TGS 703 and other gold(III) complexes present anti-inflammatory potential and may be applied therapeutically in the treatment of IBD.

44

TAKASAKA, Yuichi, Ryo FUJII, Naoki YAMADA, Naoki FUKUMURO, Susumu SAKAMOTO, Ayumu MATSUMOTO, and Shinji YAE. "Effects of Room Temperature Aging on Adhesion of Electroless Plating Film on Silicon Using Gold Nanoparticle Catalysts." Journal of The Surface Finishing Society of Japan 70, no. 3 (March 1, 2019): 174–76. http://dx.doi.org/10.4139/sfj.70.174.

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45

Ng, I. K., K. Y. Kok, S. S. Zainal Abidin, N. U. Saidin, T. F. Choo, B. T. Goh, S. K. Chong, and S. Abdul Rahman. "Gold catalysed growth of silicon nanowires and core–shell heterostructures via solid–liquid–solid process and galvanic displacement." Materials Research Innovations 15, sup2 (August 2011): s55—s58. http://dx.doi.org/10.1179/143307511x13031890747732.

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46

Bajec, David, Matic Grom, Damjan Lašič Jurković, Andrii Kostyniuk, Matej Huš, Miha Grilc, Blaž Likozar, and Andrej Pohar. "A Review of Methane Activation Reactions by Halogenation: Catalysis, Mechanism, Kinetics, Modeling, and Reactors." Processes 8, no. 4 (April 9, 2020): 443. http://dx.doi.org/10.3390/pr8040443.

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Methane is the central component of natural gas, which is globally one of the most abundant feedstocks. Due to its strong C–H bond, methane activation is difficult, and its conversion into value-added chemicals and fuels has therefore been the pot of gold in the industry and academia for many years. Industrially, halogenation of methane is one of the most promising methane conversion routes, which is why this paper presents a comprehensive review of the literature on methane activation by halogenation. Homogeneous gas phase reactions and their pertinent reaction mechanisms and kinetics are presented as well as microkinetic models for methane reaction with chlorine, bromine, and iodine. The catalysts for non-oxidative and oxidative catalytic halogenation were reviewed for their activity and selectivity as well as their catalytic action. The highly reactive products of methane halogenation reactions are often converted to other chemicals in the same process, and these multi-step processes were reviewed in a separate section. Recent advances in the available computational power have made the use of the ab initio calculations (such as density functional theory) routine, allowing for in silico calculations of energy profiles, which include all stable intermediates and the transition states linking them. The available literature on this subject is presented. Lastly, green processes and the production of fuels as well as some unconventional methods for methane activation using ultrasound, plasma, superacids, and light are also reviewed.

47

Laskay, Ü. A., C. Garino, Y. O. Tsybin, L. Salassa, and A. Casini. "Gold finger formation studied by high-resolution mass spectrometry and in silico methods." Chemical Communications 51, no. 9 (2015): 1612–15. http://dx.doi.org/10.1039/c4cc07490d.

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48

Tseng, Shao-Chin, Hsuen-Li Chen, Chen-Chieh Yu, Yu-Sheng Lai, and Haw-Woei Liu. "Using intruded gold nanoclusters as highly active catalysts to fabricate silicon nanostalactite structures exhibiting excellent light trapping and field emission properties." Energy & Environmental Science 4, no. 12 (2011): 5020. http://dx.doi.org/10.1039/c1ee01401c.

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49

Shahriar, Sadi, Kavya Somayajula, Conner Winkeljohn, Jeremy K. Mason, and Erkin Seker. "The Influence of the Mechanical Compliance of a Substrate on the Morphology of Nanoporous Gold Thin Films." Nanomaterials 14, no. 9 (April 25, 2024): 758. http://dx.doi.org/10.3390/nano14090758.

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Nanoporous gold (np-Au) has found its use in applications ranging from catalysis to biosensing, where pore morphology plays a critical role in performance. While the morphology evolution of bulk np-Au has been widely studied, knowledge about its thin-film form is limited. This work hypothesizes that the mechanical compliance of the thin film substrate can play a critical role in the morphology evolution. Via experimental and finite-element-analysis approaches, we investigate the morphological variation in np-Au thin films deposited on compliant silicone (PDMS) substrates of a range of thicknesses anchored on rigid glass supports and compare those to the morphology of np-Au deposited on glass. More macroscopic (10 s to 100 s of microns) cracks and discrete islands form in the np-Au films on PDMS compared to on glass. Conversely, uniformly distributed microscopic (100 s of nanometers) cracks form in greater numbers in the np-Au films on glass than those on PDMS, with the cracks located within the discrete islands. The np-Au films on glass also show larger ligament and pore sizes, possibly due to higher residual stresses compared to the np-Au/PDMS films. The effective elastic modulus of the substrate layers decreases with increasing PDMS thickness, resulting in secondary np-Au morphology effects, including a reduction in macroscopic crack-to-crack distance, an increase in microscopic crack coverage, and a widening of the microscopic cracks. However, changes in the ligament/pore widths with PDMS thickness are negligible, allowing for independent optimization for cracking. We expect these results to inform the integration of functional np-Au films on compliant substrates into emerging applications, including flexible electronics.

50

Arena, Fabio, Simona Pollini, Gian Maria Rossolini, and Maurizio Margaglione. "Summary of the Available Molecular Methods for Detection of SARS-CoV-2 during the Ongoing Pandemic." International Journal of Molecular Sciences 22, no. 3 (January 28, 2021): 1298. http://dx.doi.org/10.3390/ijms22031298.

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Since early 2020, the COVID-19 pandemic has caused an excess in morbidity and mortality rates worldwide. Containment strategies rely firstly on rapid and sensitive laboratory diagnosis, with molecular detection of the viral genome in respiratory samples being the gold standard. The reliability of diagnostic protocols could be affected by SARS-CoV-2 genetic variability. In fact, mutations occurring during SARS-CoV-2 genomic evolution can involve the regions targeted by the diagnostic probes. Following a review of the literature and an in silico analysis of the most recently described virus variants (including the UK B 1.1.7 and the South Africa 501Y.V2 variants), we conclude that the described genetic variability should have minimal or no effect on the sensitivity of existing diagnostic protocols for SARS-CoV-2 genome detection. However, given the continuous emergence of new variants, the situation should be monitored in the future, and protocols including multiple targets should be preferred.

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