Rapid and sensitive detection of box turtles using an electrochemical DNA biosensor based on a gold/graphene nanocomposite

• Abu Hashem,
• M. A. Motalib Hossain,
• Ab Rahman Marlinda,
• Mohammad Al Mamun,
• Khanom Simarani and
• Mohd Rafie Johan

Beilstein J. Nanotechnol. 2022, 13, 1458–1472, doi:10.3762/bjnano.13.120

• 1 × 10−5 M. The DPV peak current increased as the reverse complementary DNA concentration increased, as seen in Figure 6a. A calibration curve was constructed using log10 concentration of DNA to test the linearity of the DNA concentration with peak current (Figure 6b). The curve exhibited good

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

• (LOQ) were determined for validation of the spectrophotometric method used for DCX quantification. Absorbance values for the amount of DCX were converted to concentration according to the standard calibration curve (r2 = 0.994). LOD and LOQ values were calculated as 0.0173 mg/mL and 0.0634 mg/mL

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• adjustments are made to its cantilever dynamics, the calibration accuracy of CPs does not fluctuate when the additional mass of the ball is the same as the cantilever. In the type of large CPs, applying the homogeneity theorem for topless cantilever beams to Equation 1 can achieve accurate calibration. These

A cantilever-based, ultrahigh-vacuum, low-temperature scanning probe instrument for multidimensional scanning force microscopy

• Hao Liu,
• Zuned Ahmed,
• Sasa Vranjkovic,
• Manfred Parschau,
• Andrada-Oana Mandru and
• Hans J. Hug

Beilstein J. Nanotechnol. 2022, 13, 1120–1140, doi:10.3762/bjnano.13.95

• oscillation amplitude, without the need of a complicated calibration [43][44][45]. Fiber-optical sensors can obtain sensitivities up to about 1 fm/ using Fabry–Pérot interferometry [46][47]. To date, however, we only implemented a simpler form of the interferometer composed of a cleaved and uncoated fiber end

DNA aptamer selection and construction of an aptasensor based on graphene FETs for Zika virus NS1 protein detection

• Nathalie B. F. Almeida,
• Thiago A. S. L. Sousa,
• Viviane C. F. Santos,
• Camila M. S. Lacerda,
• Thais G. Silva,
• Rafaella F. Q. Grenfell,
• Flavio Plentz and
• Antero S. R. Andrade

Beilstein J. Nanotechnol. 2022, 13, 873–881, doi:10.3762/bjnano.13.78

• graphene devices, whose detection range extends from 0.1 to 100 pg/mL, see Figure S5 (Supporting Information File 1) for more details. We therefore analyzed in depth the general dose-dependent responses of all seven aptasensors. Figure 5a exhibits a calibration curve for ZIKV NS1 detection, reflecting the

• /mL. The inset highlights the portion of each graphene transfer curve extending from 0.00 to 0.20 V. In each measurement, ZIKV NS1 protein was diluted in human serum, which was used as electrolyte for gating. Calibration curve for ZIKV NS1 protein detection. Percentage change in graphene resistance

Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• . The characteristic Raman signature collected from a p-doped Si wafer at 520.7 cm−1 was employed as standard calibration. Raman mapping was conducted by raster scan, where the step size of the laser spot moving over a selected area is 1 µm, and the exposure time of 0.4 s was taken at each point of the

Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading

• Agnes-Valencia Weiss,
• Daniel Schorr,
• Julia K. Metz,
• Metin Yildirim,
• Saeed Ahmad Khan and
• Marc Schneider

Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68

• incubation, samples were centrifuged. The fluorescence intensity of supernatants was measured with the spectrofluorometer Duetta™ (Horiba Europe GmbH, Oberursel, Germany) using an excitation wavelength of 493 nm and an emission wavelength of 519 nm. Concentrations were calculated using a calibration row made

• B: 90% acetonitrile, 10% Milli-Q® water and 0.1% trifluoro acetic acid. The flow rate was 0.8 mL/min, and a gradient was set from 100% A to 100% B in 15 min. The concentration was determined using a calibration row by different lysozyme concentrations and the resulting AUC/min extracted from the

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

• Sarani Sen,
• Anurag Roy,
• Ambarish Sanyal and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

• due to π–π* transition was noted at 273 nm using ethanol as blank, and a calibration curve was plotted to compare the results obtained from the proposed nanosensor. Material characterization Voltammetric studies were carried out using an IVIUMStat electrochemical analyzer (Model: A09050, Iviumstat

• as the concentration of PT enhanced, indicating a diffusion-controlled process [40]. The concentration-dependent linear plot depicts good linearity (Figure 9B, Figure 9C) with a calibration equation of Ip (μA) = 3.5735 [PT] + 12.018 (R² = 0.9871) for the range of 0.1–11 μM, Ip (μA) = 0.2916 [PT

• linear curve (i.e., 0.03–0.15 nM)] and limit of quantification (LOQ = [(10 * SD of blank)/slope]) were calculated as 10.9 pM and 36.5 pM, respectively, from the lower calibration equation [39][41]. The selectivity of the proposed ERGO/GCE modified nanosensor (Figure 9D) was investigated in the presence

A new method for obtaining the magnetic shape anisotropy directly from electron tomography images

• Cristian Radu,
• Ioana D. Vlaicu and
• Andrei C. Kuncser

Beilstein J. Nanotechnol. 2022, 13, 590–598, doi:10.3762/bjnano.13.51

• circular transversal cross section. Using a calibration of 1.47 nm/px, it can be estimated that the MNPs have a cross section with an average diameter of roughly 30 nm whereas their length is, on average, slightly above 40 nm, which is compatible with the XRD measurements. Orientation data is given in

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

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

• liquid chromatography assay For the quantitative determination of EGCG, the optimal wavelength of 292 nm was used. The calibration curve obtained from high-performance liquid chromatography (HPLC) was linear between 15.625 to 1000 µg/mL with a high correlation coefficient (y = 1.0548x + 4.7737, r2

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

• calibration curve for the dependence of the catalytic current values on the concentration of H2O2. A linear relationship was obtained in the range from 10 to 1800 µM (R = 0.99874). The sensitivity of the obtained CuO electrode is 439.19 μA·mM−1. The calculated limit of detection (LOD) is 1.34 μM, assuming

• frequences. Measurements were carried out in 0.1 M NaOH solution containing 500 µM H2O2. (a) Amperometric response of the nanostructured CuO electrode in 0.1 M NaOH with stepwise addition of H2O2 at concentrations from 10 to 1800 μM and (b) the corresponding calibration curve (SD = 3.5%, n = 5). (a

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

• ) at 37 °C (n = 3). All of the released medium was removed and 5 mL of fresh solution was added at predetermined time intervals. The amount of drug released was assayed using a UV spectrophotometer. For calibration and validation of ampicillin trihydrate release, solutions were prepared at 2.5–30 µg/mL

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

• was recorded using a UV–vis spectrophotometer (Shimadzu UV-3600 UV–vis–NIR spectrophotometer). A calibration curve was prepared with bovine serum albumin (BSA) at concentration values of 0, 1, 2, 4, 6, 8, and 10 µg/mL in PBS to enable a correlation between the measured absorbance and protein

• concentration. Then, the concentration of unbound Erb was calculated from its absorbance at 595 nm using the BSA calibration curve. The concentration of bound Erb was calculated by subtracting the unbound amount from the Erb added to the nanoparticles during synthesis. According to this, SPION@bPEI-Erb

Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96

• position was recorded with an optical lever system consisting of a detection laser and a quadrant photodiode. The photodiode signal was converted into amplitude and phase at the drive frequency using a lock-in amplifier. The OLS resulting from the above calibration procedure is only valid for quasistatic

• shape during the OLS calibration, it is only a matter of multiplying the observed OLS by a ratio of the deflection to slope for a cantilever deforming under a point load applied at the location of the probe tip (assumed from manufacturer specifications) to extract a calibration parameter that can

• convert between photodiode voltage and cantilever slope. This provides a calibration parameter that remains valid in all measurement circumstances. Analytical model The core of the computational exploration is the partial differential equation (PDE) governing the dynamics of the AFM cantilever. At rest

Plasmon-enhanced photoluminescence from TiO₂ and TeO₂ thin films doped by Eu³⁺ for optoelectronic applications

• Marcin Łapiński,
• Jakub Czubek,
• Katarzyna Drozdowska,
• Anna Synak,
• Wojciech Sadowski and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2021, 12, 1271–1278, doi:10.3762/bjnano.12.94

• background subtraction and the least-square Gaussian–Lorentzian – GL(30) curve fitting algorithm. Calibration of obtained spectra to the binding energy of 285 eV for C 1s was conducted. Additionally, a built-in Ar ion gun was used to etch the surface of the films. To obtain depth profiles of the chemical

Enhancement of the piezoelectric coefficient in PVDF-TrFe/CoFe₂O₄ nanocomposites through DC magnetic poling

• Marco Fortunato,
• Alessio Tamburrano,
• Maria Paola Bracciale,
• Maria Laura Santarelli and
• Maria Sabrina Sarto

Beilstein J. Nanotechnol. 2021, 12, 1262–1270, doi:10.3762/bjnano.12.93

• using a scan rate of 0.5 Hz. An alternating voltage with a frequency of 15 kHz was applied to the tip. In order to obtain a quantitative evaluation of d33, the amplitude of the PFM signal is measured as function of the applied voltage Vac in the selected range of 1–5 V. First, a calibration sample of

• periodically poled lithium niobate (PPLN), with a known value of the piezoelectric coefficient (d33PPLN = 7.5 pm/V), is measured. Then, the sample under investigation is tested and the PPLN is measured again. The two piezoelectric calibration signals of PPLN are compared for each value of the applied voltage

• Vac. If the difference between them is less than 20%, the measurement of the sample under test is considered reliable [2][3]. The calibration factor ξ = mPPLN/d33PPLN (in which mPPLN is the slope of the straight line of the amplitude of the PFM signal vs Vac, and d33PPLN is the known piezoelectric

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

• product, easy assembly, self-calibration, and no defects [55]. The prepared components may further be used as modular “building blocks” for building higher-order upper structures with increased complexity and functionality [56]. Metal coordination can become a strong interaction due to its near-covalent

Open-loop amplitude-modulation Kelvin probe force microscopy operated in single-pass PeakForce tapping mode

• Gheorghe Stan and
• Pradeep Namboodiri

Beilstein J. Nanotechnol. 2021, 12, 1115–1126, doi:10.3762/bjnano.12.83

• calibration for the gain of the cantilever’s transfer function. DH-KPFM has found applications on sensitive materials and solid–liquid interfaces where conventional CL KPFM does not perform very well [43]. CPD measurements in an OL operation have also been demonstrated in more inclusive scanning probe modes

In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures

• Olena M. Kapran,
• Roman Morari,
• Taras Golod,
• Evgenii A. Borodianskyi,
• Vladimir Boian,
• Andrei Prepelita,
• Nikolay Klenov,
• Anatoli S. Sidorenko and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68

• were used for the calibration of the etching rates of the films. MLs are patterned into micrometer-scale bridges with multiple contacts using photolithography and reactive ion etching. A scanning electron microscopy (SEM) image of one of the studied samples is shown in Figure 1a. Control of the

Fate and transformation of silver nanoparticles in different biological conditions

• Barbara Pem,
• Marija Ćurlin,
• Darija Domazet Jurašin,
• Valerije Vrček,
• Rinea Barbir,
• Vedran Micek,
• Raluca M. Fratila,
• Jesus M. de la Fuente and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2021, 12, 665–679, doi:10.3762/bjnano.12.53

• , Perkin Elmer, Shelton, USA). The silver standard solution (1000 mg/L in 5% HNO3) from Merck (Darmstadt, Germany) was used for calibration. All prepared AgNPs were characterized by means of shape, primary size, size distribution, and surface charge in UPW. The particle visualization was performed by TEM

On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations

• Limin Wang,
• Aisha Adebola Womiloju,
• Christiane Höppener,
• Ulrich S. Schubert and
• Stephanie Hoeppener

Beilstein J. Nanotechnol. 2021, 12, 541–551, doi:10.3762/bjnano.12.44

• calibration curve to obtain a monolayer of 4-ATP (Figure S4), a reference Raman spectrum of 4-ATP self-assembled on a non-treated substrate (Figure S5), a table indicating the corresponding peak assignment (Table S1), a reference Raman spectrum of 4-ATP acquired on a water-treated substrate (Figure S6), EDX

Determining amplitude and tilt of a lateral force microscopy sensor

• Oliver Gretz,
• Alfred J. Weymouth,
• Thomas Holzmann,
• Korbinian Pürckhauer and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2021, 12, 517–524, doi:10.3762/bjnano.12.42

• frequency-modulation atomic force microscopy, the tip oscillates parallel to the surface. Existing amplitude calibration methods are not applicable for mechanically excited LFM sensors at low temperature. Moreover, a slight angular offset of the oscillation direction (tilt) has a significant influence on

• for a given amplitude and tilt. Finally, the amplitude and tilt are determined by fitting the simulation output to the data with oscillation. Keywords: frequency-modulation atomic force microscopy; lateral force microscopy; amplitude calibration; tilt estimation; Introduction Frequency-modulation

• calibration factor that relates the recorded amplitude signal of the oscillation in volts to the real oscillation amplitude in meters. At room temperature the thermal excitation of the sensor can be used to calibrate the amplitude [18]. For low temperatures, another method has to be used since the thermal

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

• as the reference sample. The TEM images were obtained by using a Jeol ARM 200F high-resolution transmission electron microscope. The silver concentration in the AgNP dispersion was determined by FAAS using the GBC 932 plus instrument. The calibration was made using the silver standard solution

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

• Petronela Prepelita,
• Florin Garoi and
• Valentin Craciun

Beilstein J. Nanotechnol. 2021, 12, 354–365, doi:10.3762/bjnano.12.29

• 284.8 eV in the inherently contaminated film are observed. The carbon peak represents the carbon absorbed at the surface, after which the energy calibration of the other spectra was done [47][48]. The contaminated carbon layer in the atmosphere becomes increasingly thinner with increasing film thickness