Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections

• Sharif Abdelghany,
• Walhan Alshaer,
• Yazan Al Thaher,
• Maram Al Fawares,
• Amal G. Al-Bakri,
• Saja Zuriekat and
• Randa SH. Mansour

Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43

• isocratic composition of 0.025 M phosphoric acid (pH 3.0 ± 0.1) previously adjusted with triethylamine/acetonitrile (80:20 v/v), eluted at a flow rate of 1.5 mL/min. The injection volume was 20 µL. The drug concentration was then determined according to a calibration curve. The calibration curve was plotted

• × phosphate-buffered saline (PBS), pH 7.4, for 15 min. A section of full-thickness human skin was placed, with the stratum corneum facing upward, onto a piece of tissue paper soaked with PBS in a weighing boat. CIP_MN1 were adhered to a piece of plastic tape and manually applied to the skin. To prevent the

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

Ethosomal (−)-epigallocatechin-3-gallate as a novel approach to enhance antioxidant, anti-collagenase and anti-elastase effects

• Çiğdem Yücel,
• Gökçe Şeker Karatoprak,
• Sena Yalçıntaş and
• Tuğba Eren Böncü

Beilstein J. Nanotechnol. 2022, 13, 491–502, doi:10.3762/bjnano.13.41

• regarding organoleptic properties, pH values, and viscosity. Stability studies were conducted for three months and changes in characterization parameters and residual EGCG content of ETHs were examined. Besides, for ETHG, organoleptic properties, pH values (every two weeks), and viscosity (first and twelfth

• obtained in the F3-coded ETH. Afterward, the ethosomal gel formulation was prepared by dispersing the F3 formulation in 1% (w/v) Carbopol 980 gel. Next, its organoleptic properties (i.e., color and homogeneity), viscosity and rheological properties, and pH values were evaluated. It was found suitable to

• use Carbopol 980 as the gelling agent at a ratio of 1:1 (v/v) due to its suitable organoleptic properties, pH value, viscosity, and its ability to homogeneously mix with the ethosome. A transparent, homogeneous, and smooth ethosomal gel system with a skin-compatible pH value (5.60) was obtained (Table

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• nanotetrapods [26]. Size and shape of the ZnO NPs depend on the type of precursor salts used (e.g., chlorides, sulfates, nitrates, or perchlorates), the molar ratio between reagents, the reaction temperature, the pH value, the ionic concentration of the medium, and other reaction parameters. The main advantage

Tunable superconducting neurons for networks based on radial basis functions

• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Igor I. Soloviev,
• Mikhail Yu. Kupriyanov,
• Maxim V. Tereshonok and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2022, 13, 444–454, doi:10.3762/bjnano.13.37

• = 1 μm, and total thickness d = 80 nm (this corresponds to the spacer thickness ds =5 nm) the estimated kinetic inductance is about 7 pH in the closed state and about 15 pH in the open state. For comparison, the geometric inductance of such a strip is of the order of 1 pH. Conclusion We have

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures

• Irena Mihailova,
• Vjaceslavs Gerbreders,
• Marina Krasovska,
• Eriks Sledevskis,
• Valdis Mizers,
• Andrejs Bulanovs and
• Andrejs Ogurcovs

Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35

• = 0 V vs Ag/AgCl and a scan rate of 100 mV/s. As buffer solution, 0.1 M NaOH (pH 12.7) was used. For the determination of H2O2, 0.1, 0.25, 0.5, 0.65, 0.85, 1, and 5 mM concentrations were used. Measurements were carried out five times for each of the indicated concentrations, and the curves in the

• following sections show the averaged data from all measurements. To determine the optimal scanning parameters that provide the maximum sensitivity of the sensor, the dependence of the electrochemical response on the pH of the buffer solution and on the scanning speed was studied. Impedance spectroscopy was

• pH of the buffer solution and on the pulse frequency was studied. Current response study For the current response study (i–t measurement), a constant voltage U = −0.7 V vs Ag/AgCl was applied to the cell and the current was measured. 0.1 M NaOH was used as buffer solution. The measurement was started

Alcohol-perturbed self-assembly of the tobacco mosaic virus coat protein

• Ismael Abu-Baker and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2022, 13, 355–362, doi:10.3762/bjnano.13.30

• and prevent the formation of helical rods at low pH. A high alcohol content favours stacked disk assemblies and large rafts, while a low alcohol concentration favours individual disks and short stacks. These effects appear to be caused by the hydrophobicity of the alcohol additive, with isopropyl

• range of different structures depending mainly on pH and ionic strength (Figure 1). Above neutral pH and at low to moderate ionic strength, the protein exists primarily as a mixture of monomers and small oligomers. This mixture is known as A-protein [17]. Around pH 6.5–7.0, TMV-cp assembles into achiral

• bilayer disks composed of 17 monomers per layer, 18 nm in diameter with a 4 nm central channel. At high ionic strength and non-acidic pH, these disks can stack on top of each other to form non-helical, rod-like assemblies. There are several known disk aggregates that can be difficult to distinguish

A broadband detector based on series YBCO grain boundary Josephson junctions

• Egor I. Glushkov,
• Alexander V. Chiginev,
• Leonid S. Kuzmin and
• Leonid S. Revin

Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27

• (Z) = RL, dIm(Z)/dω = 2LL, and . For the serial resonance at 250 GHz, RL = 43 Ω, LL = 500 pH, and CL = 0.8 fF. Figure 5, right, shows the current–voltage characteristics (IVCs) of a single junction with the antenna under the influence of an external signal. A bias current regime with the optimum

The effect of metal surface nanomorphology on the output performance of a TENG

• Yiru Wang,
• Xin Zhao,
• Yang Liu and
• Wenjun Zhou

Beilstein J. Nanotechnol. 2022, 13, 298–312, doi:10.3762/bjnano.13.25

• of a metal and a polymer. There are different charge densities on different kinds of metal surface nanomorphology, which significantly influences the output performance of the TENG. Copper samples with different nanomorphology were obtained by controlling pH value, current density, electrolyte

• freely. Therefore, there is no high charge density on the tip surface of the polymer surface. Here, size and morphology of nanoscale copper were controlled by adjusting current density, temperature, pH value, and solution concentration during electrodeposition. The effects of different morphologies and

• and copper oxide was activated at the same time. After acid oil removal, the copper sheets were washed with deionized water at 25 and 50 °C, and the residuals from the previous process were cleaned to avoid polluting the electroplating solution. Different pH values were set using 1 M sulfuric acid

Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals

• Xiaoyan Ma,
• Haoning Gong,
• Kenji Ogino,
• Xuehai Yan and
• Ruirui Xing

Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23

• , and allergens [17]. In spite of the tremendous potential, Myr possesses the same shortcomings as many hydrophobic small molecules, namely low bioavailability, poor water solubility and rapid degradation at pH > 6.8, which limits its clinical therapeutic potential [22]. GSH consists of glycine

• quantitative stoichiometry analysis. The quantitative component analysis by UV–vis and ICP-OES proved that the molar ratio of Myr/GSH/Zn2+ was close to 1:1:1 (Supporting Information File 1, Table S1 and Figure S1). The UV–vis absorption spectra of pure Myr dispersed in 0.1 M NaOH (pH 13), Myr/Zn2+ complex (pH

• 5.5), and MZG nanoparticles (pH 5.5) were measured. The UV–vis absorption spectrum of MZG nanoparticles exhibited a blue shift at 550 nm, compared with Myr/Zn2+, which was assigned to the charge transfer between GSH and Zn2+ (Figure 2c). These results demonstrated that Zn2+ as the coordination

Systematic studies into uniform synthetic protein nanoparticles

• Nahal Habibi,
• Ava Mauser,
• Jeffery E. Raymond and
• Joerg Lahann

Beilstein J. Nanotechnol. 2022, 13, 274–283, doi:10.3762/bjnano.13.22

• water and ethanol with a 9:1 (v/v) ratio. The exception was insulin and mucin-based SPNPs. Because insulin has poor solubility at neutral pH, acetic acid at 10% (v/v) was added to the solvent mixture to ensure miscibility. Due to its high molecular weight, mucin was used at 2% (w/v). NHS-PEG-NHS

Effects of drug concentration and PLGA addition on the properties of electrospun ampicillin trihydrate-loaded PLA nanofibers

• Tuğba Eren Böncü and
• Nurten Ozdemir

Beilstein J. Nanotechnol. 2022, 13, 245–254, doi:10.3762/bjnano.13.19

• under nitrogen atmosphere. Encapsulation efficiency of electrospun nanofibers Nanofibers (1 × 1 cm) were weighed and 1 mL of dichloromethane was added to dissolve fiber mats and 1 h later 7 mL of phosphate buffer solution (pH 7.4) was added to dissolve the drug released from the nanofibers (n = 3

• . Encapsulation efficiency = (the amount of drug loaded/theoretical drug amount in the nanofiber) × 100. In vitro drug release The static method was used to evaluate the in vitro drug release of the nanofiber mats. Nanofiber mats (2 × 2 cm) were weighed and incubated in 5 mL of phosphate buffer solution (pH 7.4

Relationship between corrosion and nanoscale friction on a metallic glass

• Haoran Ma and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2022, 13, 236–244, doi:10.3762/bjnano.13.18

• -spinning technique and provided by the Physics Institute at the University of Basel (Switzerland). The X-ray diffraction of Cu Kα radiation (XRD) verified the amorphous nature of the ribbons. All friction experiments were conducted at room temperature in 0.2 M phosphate buffer (Na2HPO4 + NaH2PO4, pH ≈ 7

Engineered titania nanomaterials in advanced clinical applications

• Padmavati Sahare,
• Paulina Govea Alvarez,
• Juan Manual Sanchez Yanez,
• Gabriel Luna-Bárcenas,
• Samik Chakraborty,
• Sujay Paul and
• Miriam Estevez

Beilstein J. Nanotechnol. 2022, 13, 201–218, doi:10.3762/bjnano.13.15

• of hydroxy groups elicits hydrophobicity [24]. The primary physical properties of titanium dioxide that contribute to its biocompatibility are high corrosion resistance, the thermodynamic state at low physiological pH values, the isoelectric point of 5–6, the low ion formation tendency in aqueous

• environments, and a high strength-to-weight ratio. Moreover, titanium is somewhat negatively charged at physiological pH values because of the formation of a passive oxide layer, and its dielectric constant is equivalent to that of water [25]. The specific energy structure of TiO2 is responsible for its

• hindrance inside the tubular structure. This stage of drug release is known as sustained release. The controlled release of drugs is triggered by various external or internal stimuli. Changes in pH value, redox reactions, and enzyme activity are internal stimuli, while light, magnetic fields, and ultrasound

A comprehensive review on electrospun nanohybrid membranes for wastewater treatment

• Senuri Kumarage,
• Imalka Munaweera and
• Nilwala Kottegoda

Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10

• mixture of PVA, sodium alginate, and PEO with incorporated nano-sized ZSM5 zeolite, which contains hydroxy functional groups (HZSM5). The maximum adsorption values of Th4+ and U6+ ions were found to be 274.6 and 144.7 mg/g, respectively, at a HZSM5 content of 10 wt %, an adsorbent dosage of 1 g/L, and pH

• fused SiO2 NPs. The prepared nanohybrid showed efficient separation of oil and water with excellent stability in the range of pH 2–12, indicating its potential to be used in oil spill cleanup and the treatment of industrial oil-polluted water [70]. Ma and co-workers also fabricated an oil–water

• work, a mildly hydrolyzed PAN membrane has been modified by fusing bovine serum albumin (BSA) obtained from laboratory wastes, and it has shown a maximum dye removal capacity of 434.78 mg/g, at pH 12 for TBO. The membrane has the ability to be regenerated by eluting the dye completely with 1 M NaCl or

Bacterial safety study of the production process of hemoglobin-based oxygen carriers

• Axel Steffen,
• Yu Xiong,
• Radostina Georgieva,
• Ulrich Kalus and
• Hans Bäumler

Beilstein J. Nanotechnol. 2022, 13, 114–126, doi:10.3762/bjnano.13.8

• the CCD method after precipitation, as well as after cross-linking, dissolution, and final washing steps are shown in Figure 1. The zeta potential of HbMP in phosphate-buffered saline (PBS), pH 7.4, was −8.51 ± 0.9 mV. The zeta potential in PBS, pH 7.0, of E. coli was −16 mV, that of S. epidermidis

• by centrifugation and washed three times with 0.9% NaCl. The particles were resuspended in a 0.02% GA solution and incubated for 1 h at room temperature on a shaker (cross-linking). After another centrifugation, the excess GA was quenched with 0.1 M of glycine. A solution of 0.2 M of EDTA pH 7.4 was

• utilizing an excitation wavelength of 488 nm and a 505 nm long-pass emission filter. The zeta potential of HbMP in 0.9% NaCl (pH 7.4, conductivity 17.2 ± 0.9 mS/cm) was measured using the Zetasizer Nano ZS instrument. For the determination of the concentration of free hemoglobin in the HbMP suspension

Theranostic potential of self-luminescent branched polyethyleneimine-coated superparamagnetic iron oxide nanoparticles

• Rouhollah Khodadust,
• Ozlem Unal and
• Havva Yagci Acar

Beilstein J. Nanotechnol. 2022, 13, 82–95, doi:10.3762/bjnano.13.6

• 80 °C under argon atmosphere. The black solution was cooled to room temperature after 30 min and acidified to pH 5 with CH3COOH (Lachema, Czech Republic). The final product SPION@bPEI was washed with DI water using 30 kDa Amicon centrifugal filters and stored at room temperature. The total organic

• -hydroxysulfosuccinimide (sulfo-NHS) (Sigma-Aldrich, USA) in 2-(N-morpholino)ethanesulfonic acid (MES) buffer (Biomatik, Canada) at pH 6.0 at room temperature for 15 min. Then, NHS-activated Erb (152 kDa) was washed with PBS (Biomatik, Canada) using an ultracentrifugation filter (10 kDa MWCO Amicon) and then added to 120

• quantified by the absorbance at 260 nm using the Nanodrop. Different volumes of PIC or plasmid (500 µg/mL) and SPION@bPEI (5 mg/mL) in HEPES-buffered glucose (HBG, 20 mM of HEPES, 5% w/v of glucose) pH 7.4 were mixed at a final volume of 250 µL and incubated at room temperature for 30 min to generate a

Biocompatibility and cytotoxicity in vitro of surface-functionalized drug-loaded spinel ferrite nanoparticles

• Sadaf Mushtaq,
• Khuram Shahzad,
• Tariq Saeed,
• Anwar Ul-Hamid,
• Bilal Haider Abbasi,
• Nafees Ahmad,
• Waqas Khalid,
• Muhammad Atif,
• Zulqurnain Ali and
• Rashda Abbasi

Beilstein J. Nanotechnol. 2021, 12, 1339–1364, doi:10.3762/bjnano.12.99

• specificity with significantly higher (p < 0.005) drug release in an acidic environment (pH 5.5). The nanoparticles were highly colloidal (zeta potential = −35 to −26 mV) in deionized water, phosphate buffer saline (PBS), and sodium borate buffer (SBB). They showed elevated and dose-dependent cytotoxicity in

• ) dispersed in deionized water, sodium borate buffer (SBB) pH 9.0, phosphate buffer saline (PBS) pH 7.4, and DMEM were used for zeta potential measurements. The purpose of using buffers (i.e., SBB, PBS) was to get indirect surface charge information. Deionized water was used to check the influence of

• applications [30]. All samples have lower PDI values (0.13–0.33) which indicates a uniform distribution of NPs in different dispersion media (Table 5). pH-dependent drug-loading and drug-release kinetics The UV–vis-based confirmation of drug (DOX and MTX) attachment to PMA-coated MFe2O4 (M = Fe, Co, Zn, Ni

Identifying diverse metal oxide nanomaterials with lethal effects on embryonic zebrafish using machine learning

• Richard Liam Marchese Robinson,
• Haralambos Sarimveis,
• Philip Doganis,
• Xiaodong Jia,
• Marianna Kotzabasaki,
• Christiana Gousiadou,
• Stacey Lynn Harper and
• Terry Wilkins

Beilstein J. Nanotechnol. 2021, 12, 1297–1325, doi:10.3762/bjnano.12.97

• variables related to biological effects, surface chemical composition was encoded using molecular descriptors computed for the gas phase molecules [28][29], with pH value-dependent ionization state reported to have been taken into account in one study [29].) In reality, these molecules are likely to be

• calculating the descriptors at biologically relevant pH values [29], as well as constructing physically realistic representations of the surface structures of coated and uncoated nanomaterials, rather than calculating descriptors for organic surface components as free molecules and substituting dummy values

Impact of electron–phonon coupling on electron transport through T-shaped arrangements of quantum dots in the Kondo regime

• Patryk Florków and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2021, 12, 1209–1225, doi:10.3762/bjnano.12.89

• embedded in a freestanding GaAs/AlGaAs membrane [44][45][46][47][48]. It has been shown that morphology manipulation of semiconductor QDs such as size, shape, strain distribution, or inhomogenities can influence the coupling strength of electron–phonon (e–ph) interactions [49]. The phononic effects appears

• single occupied orbitals. In consequence, the regions of occurrence of an even number of electrons in the system narrow down or completely disappear with the increase of the strength of e–ph interaction. Fluctuating spin doublets interfering with the wave propagating through a direct path give rise

• , through cotunneling processes, to the spin Fano–Kondo effect. For strong e–ph coupling, the charge ordered ground state of the system appears, and for special ranges of gate voltages and the corresponding values of e–ph coupling the charge Fano–Kondo effect occurs. Model and Formalism We consider two

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• method [81]. The as-prepared h-BiVO4 structure exhibited high sensitivity towards formaldehyde and ethanol. The formation of hyperbranched structures was found to be a function of different pH values, proton intercalation, and dissolution processes. The sensitivity in case of h-BiVO4 was found to be

Self-assembly of amino acids toward functional biomaterials

• Huan Ren,
• Lifang Wu,
• Lina Tan,
• Yanni Bao,
• Yuchen Ma,
• Yong Jin and
• Qianli Zou

Beilstein J. Nanotechnol. 2021, 12, 1140–1150, doi:10.3762/bjnano.12.85

• nucleotides, can be self-assembled [14]. Proteins are direct functional performers of countless interactions between living organisms and the outside world, and are susceptible to changes in pH value, ionic strength, and temperature [15]. Peptides have similar biocompatibility and diversity as proteins, but

• and pH values [49]. Rizzo et al. studied camptothecin loaded into Fmoc-F hydrogels in the presence of haloalkyl nanotubes. Importantly, this hybrid co-assembly method could not only control the release of camptothecin in the form of active lactone, but also showed significant inhibitory activity on

• phenylalanine to produce hydrogels driven by hydrogen bonds and π–π interactions and to form microfiber three-dimensional networks at 1 wt % and pH 7.4. The microfibers have AIE properties and strong blue emission under an ultraviolet lamp. Ni-terminated hydrogels of NI-Phe exhibit viscoelasticity with a

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

• the surrounding pH, drug loading enhancement could be pH dependent. Hence, upon synthesizing IONPs, they were coated with NOR, either at pH 5 (predominantly as cationic, NOR+) or at pH 10 (predominantly as anionic, NOR−). We observed that, drug loading at pH 5 exceeded that at pH 10 by 4.7–5.7 times

• . Furthermore, only the former (pH 5 system) exhibited a desirable slower drug release profile, compared to the free drug. NOR-coated IONPs also enable a 22 times higher drug accumulation in macrophages, compared to identical extracellular concentrations of the free drug. Thus, lowering the drug coating pH to 5

• ]. Furthermore, their interaction with IONPs may be via carboxylate groups, amine groups or by neither [27]. pH variations thus can play a key role in promoting interactions between amino acids and metal oxide surfaces [29]. NOR has also been reported to form stable complexes with Fe2+/3+ [22]. It was also

Use of nanosystems to improve the anticancer effects of curcumin

• Andrea M. Araya-Sibaja,
• Norma J. Salazar-López,
• Krissia Wilhelm Romero,
• José R. Vega-Baudrit,
• J. Abraham Domínguez-Avila,
• Carlos A. Velázquez Contreras,
• Ramón E. Robles-Zepeda,
• Mirtha Navarro-Hoyos and
• Gustavo A. González-Aguilar

Beilstein J. Nanotechnol. 2021, 12, 1047–1062, doi:10.3762/bjnano.12.78

• subcellular anticancer therapies which carry the drug and better focus it on the intended target. They are also able to contain molecules that respond to endogenous (tumor microenvironment, including redox potential, pH, enzymes, ions, or biomolecules) and/or exogenous stimuli (light, electromagnetic fields

• , instability at a physiological pH, and rapid metabolization [52]. Although nanocrystals make it possible to improve the solubility of CUR, it has been reported that this type of nanosystem can have certain stability problems, which may compromise the ability to ensure a consistent dosage [53]. Nanococrystals

• the surface of CUR nanococrystals with hyaluronic acid to increase its hydrophilicity, which resulted in a better biodistribution. They reported an advantage in the release profile as a function of pH due to a lower CUR release at pH 7.4 (40%) as compared to the acidic pH (pH 5, 80%) which is

An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• biodegradable and biocompatible nature. It was first shown in 1995 that, by introducing porosity into silicon, the material behaviour can change to provide a bioactive and even resorbable material [92]. Unlike bulk silicon, in alkalescent media (pH ≈ 7.5), porous silicon is broken down by hydrolysis in living