Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• , together with the fact that our sample preparation methodology produces many hydrogen radicals that can penetrate the surface, supports the idea that the neutral point defect behaves as a hydrogen trap. As to its identity, it has been reported in the literature that boron, when added to silicon, can behave

Gram-scale synthesis of splat-shaped Ag–TiO₂ nanocomposites for enhanced antimicrobial properties

• Mohammad Jaber,
• Asim Mushtaq,
• Kebiao Zhang,
• Jindan Wu,
• Dandan Luo,
• Zihan Yi,
• M. Zubair Iqbal and
• Xiangdong Kong

Beilstein J. Nanotechnol. 2020, 11, 1119–1125, doi:10.3762/bjnano.11.96

• the antibacterial activity. The aim of this study was to improve the antimicrobial activity of the biocompatible TiO2 material by growing the small Ag nanoparticles onto its surface. It is known that the Ag free radicals are used to kill bacteria due to their highly oxidative nature; however, when

A few-layer graphene/chlorin e6 hybrid nanomaterial and its application in photodynamic therapy against Candida albicans

• Selene Acosta,
• Carlos Moreno-Aguilar,
• Dania Hernández-Sánchez,
• Beatriz Morales-Cruzado,
• Erick Sarmiento-Gomez,
• Carla Bittencourt,
• Luis Octavio Sánchez-Vargas and
• Mildred Quintana

Beilstein J. Nanotechnol. 2020, 11, 1054–1061, doi:10.3762/bjnano.11.90

• environment. ROS refer to molecules like singlet oxygen, superoxide anion, and radicals, which are responsible for producing oxidative stress in cells followed by cell death [4]. Photosensitizer molecules must be nontoxic before irradiated with light, must produce high amounts of ROS when irradiated with

Effect of Ag loading position on the photocatalytic performance of TiO₂ nanocolumn arrays

• Jinghan Xu,
• Yanqi Liu and
• Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

• of photo-generated carriers, reducing the recombination of carriers [41]. The carriers can oxidize dissolved oxygen, H+ and H2O to active free radicals, and active free radicals can mineralize pollutants [42], where the chemical reaction is described as follows. Therefore, the increase of carrier

• concentration promotes the generation of active radicals, which increases the catalytic reaction rate and the catalytic efficiency [41][43]. In Figure 9b and 9d, a schematic diagram of the energy conversion of the two different nanocolumn structures is shown. In the AFT structure, the good transmittance of TiO2

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• . reported the in vivo formation of fluorescent gold nanoclusters for imaging the brain affected by Alzheimer’s disease (AD) [102]. The redox microenvironment in the AD brain is characterized by relatively low oxygen metabolism and more free radicals compared to that of a healthy brain. When AD occurs, a

• large amount of ascorbate and an elevated level of hydrogen peroxide, other free radicals and redox ligands appear at the lesions in the brain. Thus, HAuCl4 ions accumulated in the hippocampus can be can be potentially reduced. After tail-vein injection into four-month-old APP/PS1 male mice, imaging was

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• ), is a reversible reaction between different types of diene and dienophile resulting in thermo-responsive products. A fourth type, the thiol-ene reaction, is a reaction between thiol and alkene groups in the presence of a radical source as catalyst. The radicals can be generated through light, thermal

Facile biogenic fabrication of hydroxyapatite nanorods using cuttlefish bone and their bactericidal and biocompatibility study

• Satheeshkumar Balu,
• Manisha Vidyavathy Sundaradoss,
• Swetha Andra and
• Jaison Jeevanandam

Beilstein J. Nanotechnol. 2020, 11, 285–295, doi:10.3762/bjnano.11.21

• nanorods into the bacterial cell wall to interact with the cellular biomolecules that increases the osmotic potential and its associated irreversible damage and (ii) the generation of free reactive oxygen species (ROS) radicals that are induced by nanorods that interact with the bacterial membrane and

Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization

• Tuba Evgin,
• Alpaslan Turgut,
• Georges Hamaoui,
• Zdenko Spitalsky,
• Nicolas Horny,
• Matej Micusik,
• Mihai Chirtoc,
• Mehmet Sarikanat and
• Maria Omastova

Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14

• by increasing the content of all three GnPs. This was attributed to the high thermal stability of the GnPs, the GnPs’ shielding effect on the combustion gas diffusion into and out of the polymer during its thermal decomposition [18], the barrier effect of the GnPs, the removal of free radicals, which

Design of a nanostructured mucoadhesive system containing curcumin for buccal application: from physicochemical to biological aspects

• Sabrina Barbosa de Souza Ferreira,
• Gustavo Braga,
• Évelin Lemos Oliveira,
• Jéssica Bassi da Silva,
• Hélen Cássia Rosseto,
• Lidiane Vizioli de Castro Hoshino,
• Mauro Luciano Baesso,
• Wilker Caetano,
• Craig Murdoch,
• Helen Elizabeth Colley and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2019, 10, 2304–2328, doi:10.3762/bjnano.10.222

• formation of phenylate anions and high production of CUR radicals, since this polyphenol has demonstrated high lipophilicity (log P 3.29) and low solubility in aqueous solutions and under alkaline conditions (pH > 7) [30][31][42]. These physicochemical characteristics hinder the bioavailability and

Nitrogen-vacancy centers in diamond for nanoscale magnetic resonance imaging applications

• Alberto Boretti,
• Lorenzo Rosa,
• Jonathan Blackledge and
• Stefania Castelletto

Beilstein J. Nanotechnol. 2019, 10, 2128–2151, doi:10.3762/bjnano.10.207

• to optically detect electron spins, as paramagnetic centers in the diamond lattice or diamond surface radicals, via their coupling to the NV center. Due to interactions of the electron spins with each other, their detected spectra are often broadened to supply critical chemical information. Cross

• resonances in the NV cross-relaxation ODMR spectrum for low magnetic fields (a few milliwatts). This technique allows ODMR to replace EPR methods that require high B-fields to provide detailed spectra of the detected electron spins for identification of radicals or relaxation centers, with low concentration

• defect resolution. However, this method needs an ensemble of NVs and it is not clear how it is comparable with other methods that are able to measure dilute electron spin resonance in solids with microwave signal read-outs. In biomedical applications, EPR methods of radicals have sensitivity limitations

Improved adsorption and degradation performance by S-doping of (001)-TiO₂

• Xiao-Yu Sun,
• Xian Zhang,
• Xiao Sun,
• Ni-Xian Qian,
• Min Wang and
• Yong-Qing Ma

Beilstein J. Nanotechnol. 2019, 10, 2116–2127, doi:10.3762/bjnano.10.206

• increase in the amount of •OH and •O2− radicals. Keywords: anatase; chemical state; degradation; photocatalytic properties; S-doping; thermal chemical vapor deposition; titanium dioxide (TiO2); Introduction Anatase TiO2 with a tetragonal symmetry has widely been used for the degradation of organic

• -pyrroline-N-oxide (DMPO) were determined on a Bruker EMX plus 10/12 (equipped with Oxford ESR910 Liquid Helium cryostat). For detection of the superoxide radicals (•O2−) and hydroxyl radicals (•OH), 2.5 mg of the photocatalyst was dispersed in 1 mL DMPO/methyl alcohol solution or DMPO/H2O solution. The

• to generate electron–hole pairs, i.e., TiO2 + hν = TiO2 + e− + h+. Superoxide radicals are then formed by the reaction of the electrons with the O2 adsorbed at the surface of the TiO2 particles, i.e., e− + O2 → •O2−. The holes react with water or hydroxyl groups to form hydroxyl radicals, i.e., h

Synthesis of highly active ETS-10-based titanosilicate for heterogeneously catalyzed transesterification of triglycerides

• Muhammad A. Zaheer,
• David Poppitz,
• Khavar Feyzullayeva,
• Marianne Wenzel,
• Jörg Matysik,
• Radomir Ljupkovic,
• Aleksandra Zarubica,
• Alexander A. Karavaev,
• Andreas Pöppl,
• Roger Gläser and
• Muslim Dvoyashkin

Beilstein J. Nanotechnol. 2019, 10, 2039–2061, doi:10.3762/bjnano.10.200

• exhibits signals at g = 2.069 and g = 2.008, which can be assigned to peroxy radicals Si–O–Ο• (peak EPR-1) and non-bridging oxygen Si–O• (peak EPR-2) resulting from the desilication process [58], respectively. It is worth noting that no EPR signals from Ti(III) species with typical g values in the range of

• OH groups on the surface of the created mesopores originating from the partial removal of TiO6 octahedra and SiO4 tetrahedra from the framework and subsequent protonation of the oxygen radicals. The quantitative information of the surface modification was obtained from the 29Si MAS NMR experiments

Porous silver-coated pNIPAM-co-AAc hydrogel nanocapsules

• William W. Bryan,
• Riddhiman Medhi,
• Maria D. Marquez,
• Supparesk Rittikulsittichai,
• Michael Tran and
• T. Randall Lee

Beilstein J. Nanotechnol. 2019, 10, 1973–1982, doi:10.3762/bjnano.10.194

• and stirred for 30 min. Due to the possibility of oxygen intercepting radicals and disrupting the polymerization process, argon gas was bubbled through the stirred solution for 30 min to remove any oxygen. Blanketed with argon, the mixture was heated to 70 °C in an oil bath and then KPS (0.111 g; 4.11

Lipid nanostructures for antioxidant delivery: a comparative preformulation study

• Elisabetta Esposito,
• Maddalena Sguizzato,
• Markus Drechsler,
• Paolo Mariani,
• Federica Carducci,
• Claudio Nastruzzi,
• Giuseppe Valacchi and
• Rita Cortesi

Beilstein J. Nanotechnol. 2019, 10, 1789–1801, doi:10.3762/bjnano.10.174

• , with respect to non-smokers, as well as oral leukoplakia and oral cancers, such as lip cancer. Indeed, tobacco smoke is constituted of thousands of toxic compounds, including benzene, formaldehyde, hydrogen cyanide, carbon monoxide, arsenic and radioactive components, producing free radicals that cause

Novel hollow titanium dioxide nanospheres with antimicrobial activity against resistant bacteria

• Carol López de Dicastillo,
• Cristian Patiño,
• María José Galotto,
• Yesseny Vásquez-Martínez,
• Claudia Torrent,
• Daniela Alburquenque,
• Alejandro Pereira and
• Juan Escrig

Beilstein J. Nanotechnol. 2019, 10, 1716–1725, doi:10.3762/bjnano.10.167

• inactivation of microorganisms due to its strong oxidizing power by free radical generation, such as hydroxyl and superoxide anion radicals [11][12]. Metal oxide NPs have been commonly synthesized by chemical and physical methods, which can produce a high size variability, defects and agglomeration and can

• performance of CSTiO2, induced by exposure to UV-A light (<390 nm), occurred generally through the generation of ROS and specifically from hydroxyl radicals (OH•) (through electron abstraction from water) and superoxide anion radicals O2• (generated by the reduction of O2). ROS incidence can attack microbial

BiOCl/TiO₂/diatomite composites with enhanced visible-light photocatalytic activity for the degradation of rhodamine B

• Minlin Ao,
• Kun Liu,
• Xuekun Tang,
• Zishun Li,
• Qian Peng and
• Jing Huang

Beilstein J. Nanotechnol. 2019, 10, 1412–1422, doi:10.3762/bjnano.10.139

• species [41]. The generation of particular active species in the photocatalytic process varies with the type of catalyst (mainly the energy band structure) [42]. KI, IPA and 1,4-benzoquinone (BQ) were used as scavengers for pores (h+), hydroxyl radicals (OH) and superoxide radicals (O2−), respectively, to

A biomimetic nanofluidic diode based on surface-modified polymeric carbon nitride nanotubes

• Kai Xiao,
• Baris Kumru,
• Lu Chen,
• Lei Jiang,
• Bernhard V. K. J. Schmidt and
• Markus Antonietti

Beilstein J. Nanotechnol. 2019, 10, 1316–1323, doi:10.3762/bjnano.10.130

• S5, Supporting Information File 1). In order to obtain rectified ion transport, we modified the carbon nitride nanotubes unilaterally with a solution of 3-allyloxy-2-hydroxy-1-propanesulfonic acid sodium salt (AHPA) and with allylamine (AA) (Figure 4a). As reported before [39][40], radicals can be

A highly efficient porous rod-like Ce-doped ZnO photocatalyst for the degradation of dye contaminants in water

• Binjing Hu,
• Qiang Sun,
• Chengyi Zuo,
• Yunxin Pei,
• Siwei Yang,
• Hui Zheng and
• Fangming Liu

Beilstein J. Nanotechnol. 2019, 10, 1157–1165, doi:10.3762/bjnano.10.115

• levels serve as electron traps for photogenerated electrons. In this way, the recombination of photoinduced holes and electrons is suppressed, which accelerates the transfer of electrons to dissolve oxygen molecules and to produce more superoxide radicals to degrade probe dyes [9][22]. As a result, CZO-4

Photoactive nanoarchitectures based on clays incorporating TiO₂ and ZnO nanoparticles

• Eduardo Ruiz-Hitzky,
• Pilar Aranda,
• Marwa Akkari,
• Nithima Khaorapapong and
• Makoto Ogawa

Beilstein J. Nanotechnol. 2019, 10, 1140–1156, doi:10.3762/bjnano.10.114

• , industrial and agricultural wastewater. They are based on the in situ generation of reactive species as hydroxyl radicals (OH•) with high oxidizing capability [24]. AOP include Fenton and photo-Fenton reactions based on the combination of chemical oxidants, e.g., hydrogen peroxide, and UV irradiation, and

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• action of radicals. In addition to the appearance of new bands, several peaks were shifted or changed in shape. The peaks at 1644 and 1426 cm−1 in the spectrum of the precursor chitosan were shifted to 1633 and 1404 cm−1, respectively, and the peak at 1064 cm−1 increased in intensity compared to the peak

• values of the latter polymers were ca. 35% lower than that of precursor chitosan, which indicated a lower polydispersity of the modified chitosans (Table 1). Free radicals had two functions in the modification of chitosan: (i) the degradation of the polymer by chain scission and (ii) the creation of

• reactive sites accessible for the attachment of phenolic compounds. In free-radical grafting, the key role is played by hydroxyl radicals (·OH) that are generated through ascorbate radicals as a result of H2O2-induced oxidation of AA (Scheme 1). As the reaction proceeds at RT and no toxic byproducts are

Direct growth of few-layer graphene on AlN-based resonators for high-sensitivity gravimetric biosensors

• Jimena Olivares,
• Teona Mirea,
• Lorena Gordillo-Dagallier,
• Bruno Marco,
• José Miguel Escolano,
• Marta Clement and
• Enrique Iborra

Beilstein J. Nanotechnol. 2019, 10, 975–984, doi:10.3762/bjnano.10.98

• low-damage O2 RF-plasma in a reactive ion etcher. To prevent the negatively biased substrates from being bombarded by the energetic ions present in the plasma, a glass shield was placed 1 mm apart from the surface of the substrates. This way, only thermalized reactive oxygen radicals and neutral

The systemic effect of PEG-nGO-induced oxidative stress in vivo in a rodent model

• Qura Tul Ain,
• Samina Hyder Haq,
• Abeer Alshammari,
• Moudhi Abdullah Al-Mutlaq and
• Muhammad Naeem Anjum

Beilstein J. Nanotechnol. 2019, 10, 901–911, doi:10.3762/bjnano.10.91

• , namely lipid peroxides, as well as antioxidant agents, including catalase, superoxide dismutase, glutathione, and glutathione S-transferase was conducted. A comparison at different intervals of time after the administration of a dose (5 mg/kg) of PEG-nGO was carried out. An increase in free radicals and

• the average size distribution of nGO and PEG-nGO, respectively. In vivo assays The number of free radicals produced by a dose of PEG-nGO was estimated by the comparative levels of lipid peroxides present in the control and treated groups. The level of lipid peroxides and free radical scavengers are

• were no more significantly (P* < 0.05) increased in brain and liver, indicating a recovery from the induced OS. Glutathione is a tripeptide and, in its reduced form, acts as an active scavenger of free radicals produced as a result of lipid peroxidation. The concentration levels of the reduced

Hydrophilicity and carbon chain length effects on the gas sensing properties of chemoresistive, self-assembled monolayer carbon nanotube sensors

• Juan Casanova-Cháfer,
• Carla Bittencourt and
• Eduard Llobet

Beilstein J. Nanotechnol. 2019, 10, 565–577, doi:10.3762/bjnano.10.58

• characteristic peak at 1440 cm−1 related to CH2 and CH3 radicals. Note that O–H elongations do not appear in the Raman spectra, probably due to the weak intensity of the O–H peak in Raman spectroscopy. Once these thiols had been attached to Au-MWCNTs via the SAM technique, it was not possible to detect many of

• chain. The gas sensing mechanism for detecting ethanol is, once more, related to hydrogen bonding (see Figure 6e,f). It is well-known that hydrophilic groups present more affinity to polar compounds (e.g., ethanol) than hydrophobic radicals. This concept can explain why the short hydrophilic chain thiol

Geometrical optimisation of core–shell nanowire arrays for enhanced absorption in thin crystalline silicon heterojunction solar cells

• Robin Vismara,
• Olindo Isabella,
• Andrea Ingenito,
• Fai Tong Si and
• Miro Zeman

Beilstein J. Nanotechnol. 2019, 10, 322–331, doi:10.3762/bjnano.10.31

• fluorine radicals (F*) and oxygen radicals O*, which feed two competing chemical reactions: F* and Si react to form SF4+ ions, while from the reaction of O* and Si a silicon oxyfluorine (SiOxFy) layer is formed. This layer acts as mask against F* etching, but is physically broken by sputtered ions

Zn/F-doped tin oxide nanoparticles synthesized by laser pyrolysis: structural and optical properties

• Florian Dumitrache,
• Iuliana P. Morjan,
• Elena Dutu,
• Ion Morjan,
• Claudiu Teodor Fleaca,
• Monica Scarisoreanu,
• Alina Ilie,
• Marius Dumitru,
• Cristian Mihailescu,
• Adriana Smarandache and
• Gabriel Prodan

Beilstein J. Nanotechnol. 2019, 10, 9–21, doi:10.3762/bjnano.10.2

• presence of carbon in the powder is minor and is derived from the decomposition of methyl and ethyl radicals released by volatile organometallic compounds. This fact can be explained by an insufficient (less than stoichiometricly required) quantity of oxidant for the total oxidation of alkylmetallic

• precursors to oxides (SnO2 and ZnO, in fact Zn-doped SnO2), CO2 and H2O in the laser pyrolysis reaction zone. Due to the much higher reactivity of metals, the metal oxides are formed with priority, and the unoxidized alkyl radicals from the precursors will undergo a complex process involving reactions such

• fluorine provided by SF6 decomposition with the alkyl radicals from metallic precursors) at 686.35 eV. The ≈685 eV F1s XPS peak was also detected in fluoride-doped SnO2 from milled PVdF (polyvynilidene fluoride)/SnO2 mixtures [42] and in solid or hollow fluoride-mediated hydrothermal synthesized SnO2