Key for crossing the BBB with nanoparticles: the rational design

• Sonia M. Lombardo,
• Marc Schneider,
• Akif E. Türeli and
• Nazende Günday Türeli

Beilstein J. Nanotechnol. 2020, 11, 866–883, doi:10.3762/bjnano.11.72

• targeting ligands, such as angiopep-2, TAT or EGF, allows their accumulation to be increased in these specific areas [70][78][107][176]. Although to a lower extent, gold nanorods (AuNRs) have also been used for brain delivery. AuNRs, like AuNPs, exhibit an optical feature called surface plasmon resonance

• optical window. Light in this wavelength range can penetrate more deeply into the human body thanks to the low absorption by tissue and blood, making these nanoparticles interesting for theranostic treatments [177][179][180]. By excitation of surface plasmon oscillations, local heating can be generated

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

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

• efficiency of methylene blue (MB) compared with Ag-coated TiO2 (ACT) nanocolumn arrays and pure TiO2 nanocolumns arrays. Both experimental and theoretical simulation results demonstrated that the enhanced photocatalytic performance of AFT nanocolumn arrays was attributed to the surface plasmon resonance (SPR

• ) of Ag and the absorption of light by TiO2. These results represent a promising step forward to the development of high-performance photocatalysts for energy conversion and storage. Keywords: anodic aluminum oxide template; nanocolumn arrays; photocatalysis; surface plasmon resonance; Introduction

• surface active sites [11][12]. In addition, TiO2 combined with noble metal (e.g., Au, Ag, Pt), nanostructured to form a metal–oxide structure, has been shown to greatly improve the catalytic efficiency of the material [13]. When excited by light, noble metal nanoparticles can exhibit surface plasmon

Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties

• Marta Bartel,
• Katarzyna Markowska,
• Marcin Strawski,
• Krystyna Wolska and
• Maciej Mazur

Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49

• -resolution spectra for these elements. The direct evidence for metallic silver embedded in the polymer matrix is the spin–orbit doublet recorded at 368.3 and 374.3 eV for Ag 3d5/2 and 3d3/2, respectively (Figure 5A), followed by plasmon loss peaks at 372 and 378 eV [30][31]. However, the asymmetric shape of

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

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

• single atom. Additionally, due to covalently bound ligands, the NCs show extraordinary stability under ambient conditions. While plasmonic AuNPs display size-dependent surface plasmon resonance (SPR), NCs display characteristic molecule-like electronic spectra. This is attributed to the small size and

• quantum confinement, and the evolution of continuous or quasicontinuous bands (of bulk gold) into discrete electronic states [40]. Another attractive property of AuNCs is photoluminescence (PL), a phenomenon that is much less understood than the surface plasmon resonance of plasmonic gold nanoparticles

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

• charged silica NPs as well as the disulfide linkages between cysteine blocks and gold NPs resulted in two types of functionalities in the capsule. In a similar way, the capsules incorporated with noble metal NPs (e.g., gold and silver) respond to external light illumination by increased surface plasmon

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

• Robert Kozioł,
• Marcin Łapiński,
• Paweł Syty,
• Damian Koszelow,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

• quality of the nanostructures, in terms of their use as plasmonic platforms, is reflected in the UV–vis absorption spectra. The absorption spectrum is dominated by a maximum in the range of 450–500 nm associated with the plasmon resonance. As the initial layer thickness increases, an additional peak

• : dewetting; finite-difference time-domain (FDTD) method; plasmon resonance; silver (Ag) nanostructures; thin films; UV–vis absorption; Introduction In the last decade there has been significant development in sensor-related research regarding the application in optical, medical or biological areas [1][2][3

• ][4][5]. The principle of some of these sensors is the resonant enhancement of a local electromagnetic field as well as a sharp spectral absorption, which can be achieved by exploiting localized surface plasmon resonance (LSPR). This phenomenon is based on collective oscillations of free electrons

Preparation and in vivo evaluation of glyco-gold nanoparticles carrying synthetic mycobacterial hexaarabinofuranoside

• Gennady L. Burygin,
• Polina I. Abronina,
• Nikita M. Podvalnyy,
• Sergey A. Staroverov,
• Leonid O. Kononov and
• Lev A. Dykman

Beilstein J. Nanotechnol. 2020, 11, 480–493, doi:10.3762/bjnano.11.39

• . Another advantage of using these GNPs is their strong light absorption due to localized surface plasmon resonance (LSPR) around 520 nm while colloids of GNPs smaller than 3 nm do not exhibit an LSPR and are barely colored. It is known that the color of GNP colloids dramatically depends on size and shape

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

• Changqiang Yu,
• Min Wen,
• Zhen Tong,
• Shuhua Li,
• Yanhong Yin,
• Xianbin Liu,
• Yesheng Li,
• Tongxiang Liang,
• Ziping Wu and
• Dionysios D. Dionysiou

Beilstein J. Nanotechnol. 2020, 11, 407–416, doi:10.3762/bjnano.11.31

• spectra were collected to study the optical properties of the samples. As shown in Figure 5a, the CuO/tourmaline composite exhibited higher optical adsorption than that of pure CuO, due to the plasmon resonance of the tourmaline units [24]. The band gap of CuO and CuO/tourmaline composite was calculated

Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy

• María Sanromán Iglesias and
• Marek Grzelczak

Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20

• giving rise to the so-called localized surface plasmon resonance (LSPR). The position and the bandwidth of the LSPR can be modulated by the shape of the nanocrystals and can vary between 400 and 2000 nm. The high absorption cross section (plasmonic nanoparticles absorb photons over a region about ten

• times larger than their physical diameters) [59], and the lack of photobleaching (unlike organic fluorescent dyes and semiconductor nanocrystals) are additional parameters making plasmonic nanocrystals attractive materials for biosensing. Importantly, the position of the plasmon band and its bandwidth

• are also strictly related to the local environment. The collation of a nanoparticle at a nanometric distance from the surface of another nanoparticle induces a redshift of the maximum of the surface plasmon band because of plasmon coupling, causing a color change of the solution. Thus, the control

Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO₂ core–shell nanostructures

• Bartosz Bartosewicz,
• Malwina Liszewska,
• Bogusław Budner,
• Marta Michalska-Domańska,
• Krzysztof Kopczyński and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12

• silver diffusion in Ag–TiO2 core–shell nanostructures (CSNs). Our approach comprises three simple steps starting from the synthesis of the metallic core, through its coating with titania and finally annealing leading to plasmonic hollow nanostructures with plasmon resonance in a broad spectral range. SEM

• result, to a red-shift of the plasmon resonance [20]. As can be seen from curve A in Figure 4, Ag@TiO2 CSNs have a broad absorption in the UV–vis range. This is the characteristic absorption of these composites, which does not change remarkably with a change of the shell thickness. The annealing of Ag

• @TiO2 CSNs leads to nanostructures with significantly changed optical properties as can be seen from curves B–E in Figure 4. In all cases, a red-shift of the maximum of absorption and a strengthening and widening of the plasmon resonance bands were observed. It is significant that the Ag-modified TiO2

Plasmonic nanosensor based on multiple independently tunable Fano resonances

• Lin Cheng,
• Zelong Wang,
• Xiaodong He and
• Pengfei Cao

Beilstein J. Nanotechnol. 2019, 10, 2527–2537, doi:10.3762/bjnano.10.243

• nanosensors, optical splitters, filters, optical switches, nonlinear photonic and slow-light devices. Keywords: Fano resonance; metal–dielectric–metal (MDM) waveguide; nanosensor; on-chip plasmonic structures; surface plasmon polaritons (SPPs); Introduction Surface plasmon polariton (SPP) is a unique

Formation of metal/semiconductor Cu–Si composite nanostructures

• Natalya V. Yumozhapova,
• Andrey V. Nomoev,
• Vyacheslav V. Syzrantsev and
• Erzhena C. Khartaeva

Beilstein J. Nanotechnol. 2019, 10, 2497–2504, doi:10.3762/bjnano.10.240

• [10], or can even consist of three layers [11][12]. These variations can be useful for practical applications, e.g., for enhancing the absorption capacity of particles or for plasmon–exciton interaction [13]. The presence of an inorganic shell on a metal particle often leads to a significant

Label-free highly sensitive probe detection with novel hierarchical SERS substrates fabricated by nanoindentation and chemical reaction methods

• Jingran Zhang,
• Tianqi Jia,
• Yongda Yan,
• Li Wang,
• Peng Miao,
• Yimin Han,
• Xinming Zhang,
• Guangfeng Shi,
• Yanquan Geng,
• Zhankun Weng,
• Daniel Laipple and
• Zuobin Wang

Beilstein J. Nanotechnol. 2019, 10, 2483–2496, doi:10.3762/bjnano.10.239

• chemical (CM) [5] and electromagnetic enhancement (EM) [6][7]. The CM enhancement is the main factor for charge transfer between the SERS substrate and probe molecule. The EM field enhancement is the main factor for localized surface plasmon resonance (LSPR) and significantly depends on the induced near

Abrupt elastic-to-plastic transition in pentagonal nanowires under bending

• Sergei Vlassov,
• Magnus Mets,
• Boris Polyakov,
• Jianjun Bian,
• Leonid Dorogin and
• Vahur Zadin

Beilstein J. Nanotechnol. 2019, 10, 2468–2476, doi:10.3762/bjnano.10.237

• conductive network [14][15][16]. Ag NWs are a promising material for flexible transparent electrodes [17]. Plasmon propagation and the optical properties of Ag and Au NWs make them attractive for nanophotonics as waveguides for visible light [18][19][20][21][22][23]. In all these applications, NWs may

• curved pathways for electromagnetic radiation. Any crack or other discontinuities that are introduced by bending can prevent plasmon propagation in the NW [19]. Pure bending conditions are realized in the cantilever beam bending configuration where the NW is fixed at one end and the free end is pushed by

Multiple Fano resonances with flexible tunablity based on symmetry-breaking resonators

• Xiao bin Ren,
• Kun Ren,
• Ying Zhang,
• Cheng guo Ming and
• Qun Han

Beilstein J. Nanotechnol. 2019, 10, 2459–2467, doi:10.3762/bjnano.10.236

• new opportunities to design on-chip optical devices with great tuning performance. Keywords: multiple Fano resonance; off-centered ring resonators; plasmonic waveguide; surface plasmon polaritons; symmetry-breaking; tunable resonance; Introduction Fano resonances originate from the interference of a

• reflectance). In addition to PhC waveguides, metal–dielectric–metal (MDM) waveguides are very attractive for researchers because they can support surface plasmon polaritons (SPPs) and allow for the control of light at the subwavelength scale. MDM waveguides provide an effective approach to chip-scale photonic

The role of Ag⁺, Ca²⁺, Pb²⁺ and Al³⁺ adions in the SERS turn-on effect of anionic analytes

• Stefania D. Iancu,
• Andrei Stefancu,
• Vlad Moisoiu,
• Loredana F. Leopold and
• Nicolae Leopold

Beilstein J. Nanotechnol. 2019, 10, 2338–2345, doi:10.3762/bjnano.10.224

• surface of the AgNPs. Therefore, the observed blue shift and damping of the surface plasmon resonance (SPR) peak, which is observed only after the formation of Ag+ adions, indicates an electronic contact between the AgNPs and citrate (Figure 1B) [28][29][30]. No SERS spectra of citrate were obtained at pH

Nonlinear absorption and scattering of a single plasmonic nanostructure characterized by x-scan technique

• Tushar C. Jagadale,
• Dhanya S. Murali and
• Shi-Wei Chu

Beilstein J. Nanotechnol. 2019, 10, 2182–2191, doi:10.3762/bjnano.10.211

• properties of plasmonic nanostructures differ significantly from those of the corresponding bulk materials, mainly because of two reasons, i.e., the enhancement in the surface-to-volume ratio and the appearance of resonance effects such as surface plasmon resonance (SPR). For example, the color, or more

• plasmonic nanostructures [4][5][6]. The potential applications of nonlinear nanoplasmonics include nanolasers [7], nanoantennas [8], surface plasmon polariton (SPP)-based waveguides [9], nanostructure-based optical limiters [10], nanoscopy instruments [11][12], and nanoelectronics as integrated optical

Gold-coated plant virus as computed tomography imaging contrast agent

• Alaa A. A. Aljabali,
• Mazhar S. Al Zoubi,
• Khalid M. Al-Batanyeh,
• Ali Al-Radaideh,
• Mohammad A. Obeid,
• Abeer Al Sharabi,
• Walhan Alshaer,
• Bayan AbuFares,
• Tasnim Al-Zanati,
• Murtaza M. Tambuwala,
• Naveed Akbar and
• David J. Evans

Beilstein J. Nanotechnol. 2019, 10, 1983–1993, doi:10.3762/bjnano.10.195

• confirms the formation of spherical particles for all three sizes. The surface plasmon resonance depends on the shape and the size of the NPs. For instance, ellipsoid shapes with three different axes have three different dipole modes. When the size of the spherical AuNPs increases, their SPR does not red

• functionalization of Au-CPMV. The localized surface plasmon resonance (LSPR) spectrum shifted by almost 4 nm (Figure 3A). This shift of the extinction maximum from 534 nm to 538 nm is a result of an increase in the local refractive index at the Au-CPMV surface as reported in the literature following surface

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

• -isopropylacrylamide (NIPAM) and acrylic acid (AAc). The hydrogel cores were then encased within either a porous or complete silver shell for which the localized surface plasmon resonance (LSPR) extends from visible to near-infrared (NIR) wavelengths (i.e., λmax varies from 550 to 1050 nm, depending on the porosity

• increased, water was expelled from the particle, causing the core to collapse and leading to a smaller size. Thermochromic effects in the particles can be detected by examining the extinction maximum shift from 550 to ≈600 nm, corresponding to the plasmon band of the THPC gold seeds. The red-shift observed

• broadening of the spectra is likely the result of several contributing factors, such as polydispersity of the hydrogel core particles, capsule roughness, variable capsule thicknesses, and/or overlap of multipole surface plasmon resonances. The contribution from overlapping multipole surface plasmon

Pulsed laser synthesis of highly active Ag–Rh and Ag–Pt antenna–reactor-type plasmonic catalysts

• Kenneth A. Kane and
• Massimo F. Bertino

Beilstein J. Nanotechnol. 2019, 10, 1958–1963, doi:10.3762/bjnano.10.192

• –reactor; catalysis; heterostructures; laser ablation; multicomponent; nanoparticles; 4-nitrophenol; plasmonic; Pt; Rh; Introduction Metal nanoparticles can interact with visible light through an excitation of the localized surface plasmon resonance (LSPR). The LSPR is a resonant, collective oscillation

• of the free electrons of the metal that occurs when the dielectric constants of the metal and the medium (through which the free electrons oscillate) are appropriately matched and the wavelength of the incident light is longer than the size of the nanoparticle (NP). A consequence of plasmon

• plasmon decay for monometallic Ag. However, after Pt deposition the primary pathway for plasmon decay changed to absorption, indicating the thin Pt layer provided an alternate pathway for the dissipation of energy. Combined with electrodynamic simulations of spatial distributions of LSPR energy

The influence of porosity on nanoparticle formation in hierarchical aluminophosphates

• Matthew E. Potter,
• Lauren N. Riley,
• Alice E. Oakley,
• Panashe M. Mhembere,
• June Callison and
• Robert Raja

Beilstein J. Nanotechnol. 2019, 10, 1952–1957, doi:10.3762/bjnano.10.191

• techniques were used to explore the nature of the Au species. UV–vis measurements show signals attributed to localised surface plasmon resonance for both Au/MP-SAPO-5 (Figure S8, Supporting Information File 1) and Au/HP-SAPO-5 (Figure S9, Supporting Information File 1) systems suggesting that nanoparticles

Growth dynamics and light scattering of gold nanoparticles in situ synthesized at high concentration in thin polymer films

• Corentin Guyot,
• Philippe Vandestrick,
• Ingrid Marenne,
• Olivier Deparis and
• Michel Voué

Beilstein J. Nanotechnol. 2019, 10, 1768–1777, doi:10.3762/bjnano.10.172

• mass percentages of gold were also tested (1–3 wt %). At the end of the annealing, the films became reddish. The optical transmission was measured showing a plasmon resonance near 530 nm (data not shown). On the basis of these experiments, in order to achieve AuNP synthesis within reasonable time, 2

• angle θi was set to −20°. The wavelength was set to λ = 570 ± 10 nm, slightly off-resonance with the plasmon excitation at ca. 530 nm. The results are presented in Figure 3 on a logarithmic scale. Forward scattering and backscattering correspond, respectively, to the left and right parts of the circular

• the refractive index. As the operating wavelength of the ellipsometer is off-resonance with respect to the localized plasmon wavelength (λSPR ≃ 530 nm) and the volume fraction of gold in the sample is low (fAu < 0.20%), the extinction coefficient of the film can be assumed to be small and therefore

Remarkable electronic and optical anisotropy of layered 1T’-WTe₂ 2D materials

• Qiankun Zhang,
• Rongjie Zhang,
• Jiancui Chen,
• Wanfu Shen,
• Chunhua An,
• Xiaodong Hu,
• Mingli Dong,
• Jing Liu and
• Lianqing Zhu

Beilstein J. Nanotechnol. 2019, 10, 1745–1753, doi:10.3762/bjnano.10.170

• its semi-metal bandgap structure and high anisotropy. In addition to angle-dependent photodetectors, its angle-resolved photoelectric properties may permit the development of plasmonic devices in which the surface plasmon polariton frequency has a highly directional dependence on the wave vector

Highly ordered mesoporous silica film nanocomposites containing gold nanoparticles for the catalytic reduction of 4-nitrophenol

• Mohamad Azani Jalani,
• Leny Yuliati,
• Siew Ling Lee and
• Hendrik O. Lintang

Beilstein J. Nanotechnol. 2019, 10, 1368–1379, doi:10.3762/bjnano.10.135

• diffraction peak at 2θ = 38.2°, a surface plasmon resonance peak between 500–580 nm, and the spherical shape observed in the transmission electron microscope images, as well as the visual change in color from pink to purple. Interestingly, by simply dipping the material into a reaction solution of 4

• TEM 3D tomography at low accelerating voltage with topography-based reconstruction to show the pore orientation at the various angles with the presence of AuNPs (see Supporting Information File 1 for the movie). Optical properties of AuNPs Surface plasmon resonance (SPR) peaks in the UV–vis spectrum

• 140 minutes. Summary of the d100 XRD peaks, d-spacing of mesoporous silica, the crystallite size based on calculations using Scherrer’s equation, and the surface plasmon resonance (SPR) peak maxima of the AuNPs after both types of heat treatments. Supporting Information Supporting Information File