Comparative electron microscopy particle sizing of TiO₂ pigments: sample preparation and measurement

• Ralf Theissmann,
• Christopher Drury,
• Markus Rohe,
• Thomas Koch,
• Jochen Winkler and
• Petr Pikal

Beilstein J. Nanotechnol. 2024, 15, 317–332, doi:10.3762/bjnano.15.29

• . As expected, some agglomerates and aggregates persist even after thorough dispersion. In both distributions in Figure 2, the number of particles above 500 nm is low. This is surprising as large agglomerates above 600 nm are typical for hand-shaken dispersions but are not detected here by spICP-MS

• dispersions in a gravitational field. In all cases, the median ECD calculated from the spICP-MS particle size distributions is larger than the corresponding ECD-related results of the electron microscopy measurements, which are, in turn, larger than the MinFeret-related results of the electron microscopy

Development and characterization of potential larvicidal nanoemulsions against Aedes aegypti

• Jonatas L. Duarte,
• Leonardo Delello Di Filippo,
• Anna Eliza Maciel de Faria Mota Oliveira,
• Rafael Miguel Sábio,
• Gabriel Davi Marena,
• Tais Maria Bauab,
• Cristiane Duque,
• Vincent Corbel and
• Marlus Chorilli

Beilstein J. Nanotechnol. 2024, 15, 104–114, doi:10.3762/bjnano.15.10

• volatility, make their formulation a true challenge. In this regard, nanoemulsions (NEs), which are dispersions of two immiscible liquids with one of them dispersed as small droplets [11][12], stand out as new delivery vehicles for these bioactive compounds. They are especially important to enhance the water

• nanoemulsion comprising 5% p-cymene stabilized with 1% Tween 80, with droplet sizes measuring approximately 150 nm, which maintained its stability for 60 days [31]. The zeta potential is used to predict the stability of dispersions, and its value depends on the physicochemical properties of active ingredients

Carboxylic acids and light interact to affect nanoceria stability and dissolution in acidic aqueous environments

• Matthew L. Hancock,
• Eric A. Grulke and
• Robert A. Yokel

Beilstein J. Nanotechnol. 2023, 14, 762–780, doi:10.3762/bjnano.14.63

• during its synthesis; in fact, a carboxylic acid, namely citric acid, is used in many synthesis protocols. Citric acid adsorbs onto nanoceria surfaces, limiting particle formation and creating stable dispersions with extended shelf life. To better understand factors influencing the fate of nanoceria, its

• absorption edge in the UVA region [43]. Studying the effects of UV irradiation on nanoceria would be informative for environmental applications. In biological systems, colloidal nanoceria dispersions were found to be non-toxic to fibroblasts and were capable of preventing damage from UV irradiation [44

• carboxylic acid dispersions Color change In the presence of light, the majority of the nanoceria dispersions changed color from light yellow to colorless (attributed to Ce4+ reduction to Ce3+) [47]. Nanoceria stored in the dark did not change color and remained light yellow. Dynamic light scattering (DLS

Nanoarchitectonics to entrap living cells in silica-based systems: encapsulations with yolk–shell and sepiolite nanomaterials

• Celia Martín-Morales,
• Jorge Fernández-Méndez,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2023, 14, 522–534, doi:10.3762/bjnano.14.43

• cyanobacteria and yeast cells. On the one hand, sepiolite clay mineral was used for the immobilization of these microorganisms taking into account that this natural microfibrous Mg silicate presents a wide range of porosity, the ability to generate very viscous stable dispersions, and the capability to form

On the use of Raman spectroscopy to characterize mass-produced graphene nanoplatelets

• Keith R. Paton,
• Konstantinos Despotelis,
• Naresh Kumar,
• Piers Turner and
• Andrew J. Pollard

Beilstein J. Nanotechnol. 2023, 14, 509–521, doi:10.3762/bjnano.14.42

• dispersions were then mixed to obtain graphite mass fractions as given in Table 1. To prepare the mixed GNPref/sediment samples, a fresh GNPref sample was prepared by sonication as described above. After the initial centrifugation step at 250g, however, the sediment was retained and redispersed in fresh NMP

Polymer nanoparticles from low-energy nanoemulsions for biomedical applications

• Santiago Grijalvo and
• Carlos Rodriguez-Abreu

Beilstein J. Nanotechnol. 2023, 14, 339–350, doi:10.3762/bjnano.14.29

• encapsulated in PLGA nanoparticles derived from PIC nanoemulsions [63]. These antioxidant-loaded nanoparticles feature hydrodynamic sizes between 71 and 160 nm and encapsulation efficiencies higher than 64%. The colloidal stability of the nanoparticle dispersions was not significantly affected by protein

• . Calderó; R. Montes; M. Llinàs; M. J. García-Celma; M. Porras; C. Solans, “Studies on the formation of polymeric nanoemulsions obtained via low-energy emulsification and their use as templates for drug delivery nanoparticle dispersions”, pages 922-931, Copyright (2016), with permission from Elsevier. This

Solvent-induced assembly of mono- and divalent silica nanoparticles

• Bin Liu,
• Etienne Duguet and
• Serge Ravaine

Beilstein J. Nanotechnol. 2023, 14, 52–60, doi:10.3762/bjnano.14.6

• dispersions was adjusted to 1.08 × 1015 part/L and the solution was stored at 4 °C. Assembly of one-patch silica nanoparticles The incubation of the nanoparticles was carried out in 15 mL tubes under rolling motion at 60 rpm at room temperature. A calculated volume of ethanol, water, or salty water (20 mM of

• open air at room temperature and the grids were placed in a box protected from dust. Statistics from image analysis were performed over at least 300 multipods or 200 chains. The ζ potential value of 1-PSN aqueous dispersions (pH ≈5.7) was measured using the Malvern Zetasizer 3000 HS setup (Malvern

Two-step single-reactor synthesis of oleic acid- or undecylenic acid-stabilized magnetic nanoparticles by thermal decomposition

• Mykhailo Nahorniak,
• Pamela Pasetto,
• Jean-Marc Greneche,
• Volodymyr Samaryk,
• Sandy Auguste,
• Anthony Rousseau,
• Nataliya Nosova and
• Serhii Varvarenko

Beilstein J. Nanotechnol. 2023, 14, 11–22, doi:10.3762/bjnano.14.2

• undecylenic (UA) acids, which are both used as a reagent and as a nanoparticle stabilizer, as well as the influence of their ratio to Fe(III) acetylacetonate on the properties of particles were investigated. Stable dispersions of NPM were obtained in 1-octadecene within the OA or UA ratio from 3.3 mol to 1

• mol of acetylacetonate and up to 5.5 mol/mol. Below the mentioned limit, NPM dispersions were colloidally unstable, and at higher ratios no NPM were formed which could be precipitated by an applied magnetic field. Monodisperse nanoparticles of iron oxides were synthesized with a diameter of 8–13 nm

• followed by their thermolysis in solution. This work aims to develop the synthesis of NPM dispersions by thermolysis of Fe(III) oleate or Fe(III) undecylate in a high-boiling-point solvent. Iron oxide nanoparticle dispersions were obtained via two-stage single-reactor synthesis with Fe(III) acetylacetonate

Single-step extraction of small-diameter single-walled carbon nanotubes in the presence of riboflavin

• Polina M. Kalachikova,
• Anastasia E. Goldt,
• Eldar M. Khabushev,
• Timofei V. Eremin,
• Timofei S. Zatsepin,
• Elena D. Obraztsova,
• Konstantin V. Larionov,
• Liubov Yu. Antipina,
• Pavel B. Sorokin and
• Albert G. Nasibulin

Beilstein J. Nanotechnol. 2022, 13, 1564–1571, doi:10.3762/bjnano.13.130

• facilitate chirality separation. Conventional surfactants such as sodium dodecyl sulfate (SDS) and sodium deoxycholate (DOC), as well as polyethylene glycol-based compositions, are used to obtain high-quality dispersions of individual SWCNTs [3][4][5][10]. Although given surfactants show exemplary

• biocompatibility of nucleic acids can support biomedical applications of such dispersions. Unfortunately, an extensive ultrasonic treatment required to obtain a dispersion of individual nanotubes might destroy fragile nucleic acid molecules so that their applications are somewhat inhibited. Flavin compounds are

• isoalloxazine rings and a sidewall of SWCNTs [17][18]. Flavin derivatives compounds are known to extract specific (n,m) SWCNTs from dispersions in organic solvents [19][20]. Moreover, flavin mononucleotide phosphate could be used as a stabilizer for graphene aqueous dispersions [21]. Although proven to

Orally administered docetaxel-loaded chitosan-decorated cationic PLGA nanoparticles for intestinal tumors: formulation, comprehensive in vitro characterization, and release kinetics

• Sedat Ünal,
• Osman Doğan and
• Yeşim Aktaş

Beilstein J. Nanotechnol. 2022, 13, 1393–1407, doi:10.3762/bjnano.13.115

• nanoparticle aqueous dispersion and the mucin. For this purpose, 40 mg mucin powder was dispersed in 50 mL ultrapure water and stirred for 12 h. Then, by centrifugation at 8000 rpm for 15 min, excess mucin was removed and the mucin solution was obtained. Mucin solution and nanoparticle dispersions were mixed

• at a ratio of 1:4 (mucin solution/nanoparticle dispersion, v/v) and vortexed for 90 s. Mucin–nanoparticle mixtures and aqueous dispersions of nanoparticles were incubated at 37 °C and turbidimetric measurements were conducted at 650 nm at predetermined time points (0, 30, 60, and 120 min

Efficient liquid exfoliation of KP₁₅ nanowires aided by Hansen's empirical theory

• Zhaoxuan Huang,
• Zhikang Jiang,
• Nan Tian,
• Disheng Yao,
• Fei Long,
• Yanhan Yang and
• Danmin Liu

Beilstein J. Nanotechnol. 2022, 13, 788–795, doi:10.3762/bjnano.13.69

• KP15 dispersions. The Lambert–Beer law (Equation 3) was then used to measure the concentration of the KP15 dispersions: where A is the absorbance, K is the absorption coefficient of the material, b is the absorbing layer thickness (which in this work is the width of the cuvette, i.e., 1 cm), and C is

• the concentration of the KP15 dispersions. The absorbance A and the absorption coefficient K are related to the wavelength of the incident light. To determine A and K, it is necessary to choose a specific incident wavelength. The bandgap of bulk KP15 is approx. 1.75 eV [20]. However, according to our

• influence of the surface state, a wavelength (800 nm) which is far away from the bandgap of KP15 bulk and surface state in the KP15 nanowires was chosen. Some dispersions for which we predetermined the concentration were prepared to fit and determine the absorption coefficient K. Solutions of five different

Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• et al. that controlled centrifugation can be used for the selection of liquid-phase exfoliated graphene dispersions with mean flake sizes in the range from 1 to 3.5 µm [29]. Since centrifugation is a much more facile process than exfoliation, and centrifuges are widely available, post-exfoliation

• electrochemically exfoliated graphene, nor have thin films made from dispersions following size selection through centrifugation been studied for their optoelectronic properties. Here, we present size selection through cascade centrifugation of commercially obtained electrochemically exfoliated graphene. We follow

Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids

• Adil Loya,
• Antash Najib,
• Fahad Aziz,
• Asif Khan,
• Guogang Ren and
• Kun Luo

Beilstein J. Nanotechnol. 2022, 13, 620–628, doi:10.3762/bjnano.13.54

• nanoparticles can enhance the properties of both polar and nonpolar fluids. In the current paper, dispersions of nanoparticles were carried out in hydrocarbon and aqueous-based fluids using molecular dynamic simulations (MDS). The MDS results have been validated using the autocorrelation function and previous

Stimuli-responsive polypeptide nanogels for trypsin inhibition

• Petr Šálek,
• Jana Dvořáková,
• Sviatoslav Hladysh,
• Diana Oleshchuk,
• Ewa Pavlova,
• Jan Kučka and
• Vladimír Proks

Beilstein J. Nanotechnol. 2022, 13, 538–548, doi:10.3762/bjnano.13.45

• deprotection step leading to the formation of nanogel with zwitterionic groups according to our earlier published procedure [25]. Characterization of nanogels DLS and zeta potential measurements were performed with dispersions of PHEG-Tyr and Nα-Lys-NG nanogels in PBS buffer at pH 4, 4.5, 4.7, 5.5, and 7.4 (1

Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis

• Camila Felix Vecchi,
• Rafaela Said dos Santos,
• Jéssica Bassi da Silva and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42

• final dispersions were filtered through grade-3 filter paper [44][45]. The pH determination was performed using a pHmeter calibrated with buffer solutions. The relative density of the extract was determined using a pycnometer calibrated at 20 °C in a controlled temperature environment (20 °C). To

• suitable amount of PVP was dissolved in 3 mL of absolute ethyl alcohol, and P407 was dissolved in 2 mL of the same solvent. After obtaining the individual dispersions, the P407 was poured onto the PVP, magnetically stirred for 10 min, and this mixture was poured onto the PVA under magnetic stirring for

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

• , Czech Republic 10.3762/bjnano.13.2 Abstract Sputter deposition of atoms onto liquid substrates aims at producing colloidal dispersions of small monodisperse ultrapure nanoparticles (NPs). Since sputtering onto liquids combines the advantages of the physical vapor deposition technique and classical

• monodisperse particles and provided a mathematical model for fitting the kinetic curves [89]. As a result, it was applied to any colloidal system, including colloidal dispersions of metal NPs, and finally was considered as “overcited” [90]. In reality, this mechanism describes very well the formation of sulfur

pH-driven enhancement of anti-tubercular drug loading on iron oxide nanoparticles for drug delivery in macrophages

• Karishma Berta Cotta,
• Sarika Mehra and
• Rajdip Bandyopadhyaya

Beilstein J. Nanotechnol. 2021, 12, 1127–1139, doi:10.3762/bjnano.12.84

• permeabilization [10], in turn improving the bactericidal activity of the drug, too. For biological applications, it is essential for IONPs to be stabilized with the help of stabilizing agents [11][12]. This helps to reduce the nanoparticle toxicity and facilitates the synthesis of stable nanoparticle dispersions

Progress and innovation of nanostructured sulfur cathodes and metal-free anodes for room-temperature Na–S batteries

• Marina Tabuyo-Martínez,
• Bernd Wicklein and
• Pilar Aranda

Beilstein J. Nanotechnol. 2021, 12, 995–1020, doi:10.3762/bjnano.12.75

• disproportionation reaction of Na2S2O3 in presence of concentrated H2SO4 [57]. Raffo sols are stable, aqueous colloidal dispersions of SO3−-capped sulfur NPs in the 100–500 nm range and could be readily assembled with other compounds such as cathode materials. Yet, this fabrication route of sulfur cathodes appears

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• molecules in aqueous dispersions of AgNPs are presented. The influence of temperature on the enhancement effect is discussed with respect to the supramolecular structure of water. Results and Discussion Characterisation of silver nanoparticles This article presents the SERS effect of water in aqueous

• dispersions of AgNPs. The AgNPs were synthesized according to the protocol proposed by Frank et al. [36]. Two types of nanoparticles were obtained: AgNPs blue and AgNPs yellow, which were labelled according to the colour (compare the UV–vis spectra shown in Figure S1 in Supporting Information File 1). High

• Raman spectra for pure water and aqueous dispersions of silver nanoparticles were performed at room temperature (see Figure 2). Polarised Raman measurements were carried out in x(y,y)z (parallel) and x(y,x)z (perpendicular) configurations. All spectra were normalised to the total integral intensity

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• [33]. Fan et al. synthesized MXene/holey graphene (HGO) films, to be used as electrode material in supercapacitors, through the filtration of alkalized MXene and HGO dispersions. The prepared material, when used as a composite film electrode for supercapacitors, showed a high volumetric capacitance of

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• , UCNPs in aqueous dispersions undergo minor disintegration, which also results in the quenching of their luminescence intensity [8][10][18][19][20][21][22][23]. This concentration-dependent effect is especially significant when the dispersions are highly diluted [8][19][22], when the pH value is low [22

• (pore size: 0.2 µm, Rotilab). Nylon filters were used for particles dispersed in cyclohexane and ethanol, whereas regenerated cellulose filters were used for particles dispersed in water or DMEM. Zeta potential measurements of the dispersions in ethanol and water were carried out using capillary zeta

• silica-coated UCNPs and for the UCNP cores was obtained. The dispersions were kept at 37 °C for 24 h, and centrifuged with centrifuge tubes containing membrane filters (Amicon ultracentrifuge, low-binding ultracel membrane, 3000 molecular weight cutoff (MWCO)) for 2 h at 3080g. Aliquots were diluted in

PEG/PEI-functionalized single-walled carbon nanotubes as delivery carriers for doxorubicin: synthesis, characterization, and in vitro evaluation

• Shuoye Yang,
• Zhenwei Wang,
• Yahong Ping,
• Yuying Miao,
• Yongmei Xiao,
• Lingbo Qu,
• Lu Zhang,
• Yuansen Hu and
• Jinshui Wang

Beilstein J. Nanotechnol. 2020, 11, 1728–1741, doi:10.3762/bjnano.11.155

• was obtained by dialysis and vacuum drying successively as above. This difunctionalized CNT carrier was named CNTs-PEG-PEI. Characterization of nanocarriers Different aqueous dispersions of SWCNTs were dispersed onto holey carbon film on copper grids. The sample morphologies were observed by

• (AFM) measurements, different SWCNT dispersions (ethanol/ultrapure water = 1:1) with a concentration of 0.01% were dripped on freshly cleaved mica and observed using an AFM (Dimension Icon, Bruker AXS). Drug loading and encapsulation efficiency An amount of 50 mg of different SWCNT samples were

• . Moreover, their length is much shorter than that of the raw SWCNTs, also being consistent with the TEM observations. The above results prove that the raw SWCNTs were shortened by the acid treatment, together with an improvement of the dispersion state. Thus, highly stable dispersions of individual CNTs can

Cu₂O nanoparticles for the degradation of methyl parathion

• Juan Rizo,
• David Díaz,
• Benito Reyes-Trejo and
• M. Josefina Arellano-Jiménez

Beilstein J. Nanotechnol. 2020, 11, 1546–1555, doi:10.3762/bjnano.11.137

• indicate Miller indices obtained from powder diffraction file (PDF) 74-1230. Color powders for the three different sizes as well as their color in aqueous dispersions with a concentration of 7.5 × 10−4 M. a) HRTEM image of typical Cu2O NP used in degradation of MP. Particle average size in the range of 16

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

• power impinging on the sample was between 5 and 10 mW, the spatial resolution was 2 cm−1 and the spot size was ≈1 µm2. The samples were recorded from drops of the dispersions deposited on clean silicon wafers and left to dry under vacuum. The chemical composition of the samples was investigated using X