Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications

• Aisha Kanwal,
• Naheed Bibi,
• Sajjad Hyder,
• Arif Muhammad,
• Hao Ren,
• Jiangtao Liu and
• Zhongli Lei

Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93

• % and the reported CDs were employed as a sensing probe for Fe3+ ions [61]. Devi et al. utilized Carica papaya waste as a natural source for a simple pyrolysis route and obtained a good QY of 23.7%. The reported CDs have a chromium sensitivity of 0.708 ppb in water [83]. Recently, a further increase in

• –31G diffused and polarized basis sets. An excellent agreement was found between theoretical data and experimental results [73]. An ultrasonic-assisted solvent extraction approach was employed to synthesize CDs from rice fried Codonopsis pilosula (CP). The CP-CDs possess good sensitivity and

• glutathione, as a dopant for both S and N, and a green source of celery leaves to synthesize CDs. Low-cost celery leaves containing folic acid with many –COOH and –NH2 groups contribute to high QYs. The reported CDs were novel fluorescent paper sensors and showed remarkable sensitivity and selectivity in the

Theoretical investigations of oxygen vacancy effects in nickel-doped zirconia from ab initio XANES spectroscopy at the oxygen K-edge

• Dick Hartmann Douma,
• Lodvert Tchibota Poaty,
• Alessio Lamperti,
• Stéphane Kenmoe,
• Abdulrafiu Tunde Raji,
• Alberto Debernardi and
• Bernard M’Passi-Mabiala

Beilstein J. Nanotechnol. 2022, 13, 975–985, doi:10.3762/bjnano.13.85

• above the Fermi level) that correspond to the pre-edge peaks in the O K-edge XANES spectra show sensitivity to increasing oxygen vacancy concentration. These PDOS peaks show change in intensity and splitting in response to the distortions from ideal geometric arrangements of oxygen shells surrounding

Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• paper, including pump-probe KPFM [13][20][43], time-resolved KPFM [11][12][44][45][46][47], fast free force recovery KPFM (G-Mode) [14][48][49][50], intermodulation electrostatic force microscopy (EFM) [42][51], and PeakForce tapping KPFM [52]. The fundamental detection sensitivity to electrostatic

• . These mixing products have enhanced sensitivity to electrostatic forces at the expense of localization to small tip–sample separations. By choosing ωe such that the mixing products fall on the sidebands of ω1, the SNR is improved whilst enabling single-pass scanning. There are trade-offs here in that ωe

• loop using phase-based detection [71], frequency sweeps [40][64][72], or bias modulation [10][52][73]. The advantages of CL AM-KPFM are that it is easy to implement, is standard on most commercial AFMs, and has high bias sensitivity [74]. The disadvantages of this technique are that it is limited by

Efficiency of electron cooling in cold-electron bolometers with traps

• Dmitrii A. Pimanov,
• Vladimir A. Frost,
• Anton V. Blagodatkin,
• Anna V. Gordeeva,
• Andrey L. Pankratov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 896–901, doi:10.3762/bjnano.13.80

• ; responsivity; Introduction Cooling is a key feature to improve the sensitivity of any receiver. Reliable dilution refrigerators providing temperatures below 100 mK have not yet been implemented for operation in space under zero gravity. But 3He cryostats, which provide temperatures down to 250 mK, are widely

• due to thinner tunneling barriers with higher quality. Conclusion Electron cooling is very important for highly sensitive measurements. At modern space applications, it may be the only reliable method to cool down the detector in 3He cryostats to achieve better sensitivity. Cold-electron bolometers

• are able to show electron self-cooling by a factor of five or even more [7], thus improving sensitivity, so they might be a prospective type of detectors [6]. Although we could not reach a new minimum of electron cooling at 300 mK phonon temperature, we achieved electron cooling from 200 to 33 mK and

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

• where more than one flavivirus co-circulates and YFV vaccination is mandatory. The traditional serological approaches present relatively high antigenic cross-reactivity. Molecular techniques have been successfully applied for flavivirus infection diagnosis offering the advantages of speed, sensitivity

• ZIKV NS1 protein, capable of providing a specific virus identification for application in diagnostic biosensors. In this context, biosensor platforms based on aptamers (aptasensors) are commonly used to assess and quantify in real-time, with high sensitivity, the presence of an analyte, such as a

Numerical modeling of a multi-frequency receiving system based on an array of dipole antennas for LSPE-SWIPE

• Alexander V. Chiginev,
• Anton V. Blagodatkin,
• Dmitrii A. Pimanov,
• Ekaterina A. Matrozova,
• Anna V. Gordeeva,
• Andrey L. Pankratov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 865–872, doi:10.3762/bjnano.13.77

• ) [5][6] integrated into the dipole antennas. The advantages of CEB over other types of bolometers are, in particular, their high sensitivity with background-limited operation [6][7][8] and a wide dynamic range. These qualities are largely determined by the presence of an internal self-cooling of the

• calculations for the LSPE-SWIPE The noise-equivalent power (NEP) is a measure of a minimal signal that can be detected, and it qualifies the sensitivity of a detector. The NEP is the ratio of the total system noise (which includes both the internal noise of the detector and the photon noise of the received

Self-assembly of C₆₀ on a ZnTPP/Fe(001)–p(1 × 1)O substrate: observation of a quasi-freestanding C₆₀ monolayer

• Guglielmo Albani,
• Michele Capra,
• Alessandro Lodesani,
• Alberto Calloni,
• Gianlorenzo Bussetti,
• Marco Finazzi,
• Franco Ciccacci,
• Alberto Brambilla,
• Lamberto Duò and
• Andrea Picone

Beilstein J. Nanotechnol. 2022, 13, 857–864, doi:10.3762/bjnano.13.76

• to this system, new features appear. The photoemission signal from the underlying ZnTPP layer, albeit affected by the screening action of C60 (implying a rather large surface sensitivity of the technique, as also shown in [55] on a similar system), is still detected in those spectral regions not

Temperature and chemical effects on the interfacial energy between a Ga–In–Sn eutectic liquid alloy and nanoscopic asperities

• Yujin Han,
• Pierre-Marie Thebault,
• Corentin Audes,
• Xuelin Wang,
• Haiwoong Park,
• Jian-Zhong Jiang and
• Arnaud Caron

Beilstein J. Nanotechnol. 2022, 13, 817–827, doi:10.3762/bjnano.13.72

• (PtSi-cont, manufactured from NanoSensors, Switzerland), SiOx cantilevers (Contsc, manufactured from NanoSensors, Switzerland), and Au-coated Si cantilevers (ContscAu, manufactured from NanoSensors, Switzerland). Before measurements, the sensitivity of the AFM photodiode was calibrated by recording a

• each dZ/dt-values, the temperature dependence of γ was fitted with the linear function γ(T) = γm + κ(T – Tm), where γm is interfacial at the melting point, κ is the temperature sensitivity of γ, and Tm is the melting point of eutectic Ga–In–Sn melt. The values of γm and κ are also shown as a function

• –In–Sn eutectic liquid alloy at the melting point has been reported to be = 587 mN/m, while its temperature sensitivity is κ* = −10 mN/Km [21]. This value for the surface energy is expected to be larger than the interfacial energy values determined in this work. However, the positive κ values in this

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

• actual sensitivity and the spring constant of the used cantilever were calibrated on a cleaned silica wafer by the thermal noise method by Hutter et al. [27] using a correction factor of 0.251. The data was acquired using the quantitative imaging mode (QI™) with image sizes of 5 × 5 µm and a resolution

• single nanoparticles. For the values of Young’s moduli, the respective curves were treated as follows: The determined spring constant and sensitivity must be applied to calibrate the cantilever deflection. To correct the vertical offset, a baseline subtraction is applied, and the contact point is

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

• electrocatalytic reduction peak at −0.58 V (vs Ag/AgCl) for rapid quantification of PT due to the amplified electroactive surface area of the modified electrode. At optimized experimental conditions, square-wave voltammetric analysis exhibits higher sensitivity (50.5 μA·μM−1·cm−2), excellent selectivity, excellent

• and straightforward responsive nature, high sensitivity, and selectivity leading to real-time detection [7]. A combination of a receptor, an analyte, and a transducer is made up to obtain an electrochemical sensor, in which the surface of the electrode induces redox characteristics via selective

• nanomaterials have been reported to detect PT [16][17]. However, their sensitivity and detection limit for quantifying trace amounts of PT in environmental samples are improved. The inherent electrochemical behavior of nitroaromatic OPs (e.g., paraoxon, parathion, and fenitrothion) exhibit well-defined redox

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• force This signal is measured with a lock-in amplifier and compensated by VAC control, yielding the SPV value. To improve the sensitivity, ωm is usually tuned to the second (first) resonance frequency of the cantilever, while the first (second) resonance frequency is assigned to the AFM measurement [29

• energy resolutions and the image acquisition time of AC-KPFM in the AM mode are comparable to those of the classical KPFM in the AM mode, because both methods detect the electrostatic force, and the response time of the bias feedback τ limits the image acquisition time. To reach sufficient sensitivity

• time [31]. To reach sufficient sensitivity, the value should typically be larger than 1 V. Experimental The experiments were performed by customized ultrahigh-vacuum (UHV) noncontact atomic force microscopy (NC-AFM, UNISOKU) at a temperature T of 78 K with a base pressure below 5 × 10−11 Torr. The NC

Quantitative dynamic force microscopy with inclined tip oscillation

• Philipp Rahe,
• Daniel Heile,
• Reinhard Olbrich and
• Michael Reichling

Beilstein J. Nanotechnol. 2022, 13, 610–619, doi:10.3762/bjnano.13.53

• has been applied. Additionally, a tilted cantilever has been found to lead to a modification of the tip–sample convolution [12], to enhance the sensitivity of the measurement to the probe side [13], and to influence results of multifrequency AFM and Kelvin probe force microscopy [14]. In the presence

Approaching microwave photon sensitivity with Al Josephson junctions

• Andrey L. Pankratov,
• Anna V. Gordeeva,
• Leonid S. Revin,
• Dmitry A. Ladeynov,
• Anton A. Yablokov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 582–589, doi:10.3762/bjnano.13.50

• experiments of dark matter search [10][11][12] and the corresponding program initiated by INFN in Italy [13][14][15][16][17][18][19][20][21][22]. Our experiments show that typical aluminium Josephson junctions (JJs) can indeed have a few-photon sensitivity in the microwave frequency range, and a photon

• counter can be made on their basis. We use the metastable quasi-equilibrium state of a Josephson junction, which, at low temperatures, is stable enough for thermal fluctuations and quantum tunneling, but can be easily destroyed by absorption of a single photon. We demonstrate few-photon sensitivity of our

• samples in a single-shot regime and outline the junction parameter range where approaching single photon sensitivity is possible. Results and Discussion In this section, we describe our experimental setup, as well as the measurement results and comparison with theory. To study the dynamics of a SIS tunnel

Detection and imaging of Hg(II) in vivo using glutathione-functionalized gold nanoparticles

• Gufeng Li,
• Shaoqing Li,
• Rui Wang,
• Min Yang,
• Lizhu Zhang,
• Yanli Zhang,
• Wenrong Yang and
• Hongbin Wang

Beilstein J. Nanotechnol. 2022, 13, 549–559, doi:10.3762/bjnano.13.46

• detection (LOD) was calculated to be 8.4 μM (S/N = 3). In Table 1 the analytical performance of the constructed sensors is compared with other reported methods and with sensing techniques based on GNPs. The results indicate that the proposed strategy has good selectivity and acceptable sensitivity compared

• spectral response to the presence of metal ions, which illustrates the sensitivity and selectivity for Hg2+. Further, GSH-Rh6G2 and GNPs-GSH-Rh6G2 were employed in confocal microscopy experiments using Hela cells. The experiments showed that GNPs-GSH-Rh6G2 is more easily internalized into the cells and

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

• Fluorescence detection is a powerful and effective tool for monitoring compounds with native fluorescence or labelled with an appropriate tag. For fluorescence-based detection, achieving high sensitivity via improving the signal-to-noise ratio is mandatory [104]. In order to increase the quantum yield and

• , consequently, to increase the sensitivity of fluorophores, the use of metallic nanostructures was proposed due to their localized surface plasmon resonance [105]. The improvement in the fluorescence detection efficiency can be achieved using fluorophores in the proximity of nanosubstrates, a technique named

• fluorophore and the surface plasmon field of the metallic nanostructure. This interaction leads to the enhancement of fluorophore emission, being an adequate method to improve the sensitivity of fluorescence detection of molecules. Based on the above, MEF is also referred to as plasmon-enhanced fluorescence

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

• ][25] as well as read-out circuits for quantum computing [26][27][28][29][30][31][32][33]. They realize a unique combination of a wide dynamic range and high sensitivity when receiving signals, with high performance and energy efficiency at the stage of the processing. It seems reasonable to implement

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

• concentration of H2O2 in the range from 10 to 1800 μM was obtained. The sensitivity of the obtained CuO electrode is 439.19 μA·mM−1. The calculated limit of detection is 1.34 μM, assuming a signal-to-noise ratio of 3. The investigation of the system for sensitivity to interference showed that the most common

• being horseradish peroxidase) [34][35][36], and detection is carried out through physicochemical processes of interaction between H2O2 and the enzyme. This type of sensor has high catalytic activity, sensitivity, and selectivity. However, enzyme sensors have a significant disadvantage, namely enzyme

• response and, as a consequence, the selectivity of the sensor. This type of sensor is characterized by good reproducibility of measurement, low production cost, fast response, high sensitivity and selectivity, and chemical and mechanical stability in aggressive environments [40][41][42][43][44][45][46

A chemiresistive sensor array based on polyaniline nanocomposites and machine learning classification

• Jiri Kroutil,
• Alexandr Laposa,
• Ali Ahmad,
• Jan Voves,
• Vojtech Povolny,
• Ladislav Klimsa,
• Marina Davydova and
• Miroslav Husak

Beilstein J. Nanotechnol. 2022, 13, 411–423, doi:10.3762/bjnano.13.34

• . In most cases, the cross-sensitivity toward different chemical analytes is unavoidable, regardless of their oxidizing or reducing nature. Many authors have suggested a number of ways to overcome the drawbacks of cross-sensitivity/selectivity and reliability of the sensor arrays [3][4][5]. One

• (carbon nanotubes (CNT), SnO2, TiO2) materials in a gas sensors based on nanocomposite layers with good sensitivity, temperature stability, reversibility, which was operating at room temperature. Herein, we extended our study by applying other nanocomposite sensing layers, namely PANI/ZnO, PANI/WO3

• displayed in Figure 6. The experiment consisted of 5 min of sensor exposure to a certain gas concentration and 5 min of purging at a flow rate of 100 mL·s−1. It is evident that all active layers have the highest sensitivity and clear response to NH3. All active composite layers except PANI+ZnO exhibit a

A photonic crystal material for the online detection of nonpolar hydrocarbon vapors

• Evgenii S. Bolshakov,
• Aleksander V. Ivanov,
• Andrei A. Kozlov,
• Anton S. Aksenov,
• Elena V. Isanbaeva,
• Sergei E. Kushnir,
• Aleksei D. Yapryntsev,
• Aleksander E. Baranchikov and
• Yury A. Zolotov

Beilstein J. Nanotechnol. 2022, 13, 127–136, doi:10.3762/bjnano.13.9

• analytical response rates and the toxicity of the detected compounds. Since the absorption of hydrocarbon vapors is responsible for the delivery of the analyte to the photonic crystal, a change in the sensor sensitivity is possible by varying the thickness of the sensitive PDMS layer. In the experiments

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

• growing demand for a combination of different imaging modalities to improve the detection limit and to provide image-guided therapies [41][42]. Both MRI and optical imaging are noninvasive imaging modalities. Magnetic resonance imaging provides high spatial resolution but lacks sensitivity. Optical

• imaging, on the other hand, has better sensitivity but suffers from limitations in the penetration depth in in vivo studies. However, it is quite successful in the preclinical research [43]. Hence, a combination of the two modalities provides many advantages. One of the approaches towards such structures

• sensitivity the results obtained from TEM are usually more reliable [52]. The XRD pattern of SPION@bPEI synthesized in situ indicates a crystalline magnetite structure composed of both magnetite (Fe3O4) and maghemite (Fe2O3), including nanoparticles (Figure 1c). Considering only XRD patterns it would be

Alteration of nanomechanical properties of pancreatic cancer cells through anticancer drug treatment revealed by atomic force microscopy

• Xiaoteng Liang,
• Shuai Liu,
• Xiuchao Wang,
• Dan Xia and
• Qiang Li

Beilstein J. Nanotechnol. 2021, 12, 1372–1379, doi:10.3762/bjnano.12.101

• under (almost) physiological conditions in situ. It offers nanoscale force sensitivity, the ability to work in liquid phases, and requires no staining [12][13][14]. With the development of AFM, researchers have been able to conduct extensive research on biological issues through imaging the

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

• to oxidative damage via NPs+drugs and free drug controls compared to HepG2 cells. Both NPs+DOX and NPs+MTX started to produce a significant (p < 0.05) ROS amount at 5 min exposure time with 2- to 3-fold increased effect compared to free drug controls. Lower sensitivity of HepG2 cells towards

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

• Asylum Research’s blueDrive photothermal excitation module for laser-based excitation of the cantilever. The optical lever sensitivity (OLS) corresponding to the static cantilever beam shape with a point load at the tip was calculated from a force displacement curve [32] on the silicon sample. The

Nonmonotonous temperature dependence of Shapiro steps in YBCO grain boundary junctions

• Leonid S. Revin,
• Dmitriy V. Masterov,
• Alexey E. Parafin,
• Sergey A. Pavlov and
• Andrey L. Pankratov

Beilstein J. Nanotechnol. 2021, 12, 1279–1285, doi:10.3762/bjnano.12.95

• that the simplest marker of the response level of a Josephson junction to microwave (MW) radiation is the magnitude of Shapiro steps. In the majority of works, an increase in sensitivity at low temperatures has been demonstrated [15][16][17], although a part of the papers indicate the receiver’s

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

• fluoride-co-trifluoroethylene) (PVDF-TrFE) [15][16][17]. This copolymer shows a higher piezoelectric coefficient than PVDF, while still maintaining a high flexibility, sensitivity, and mechanical durability. It is also, like PVDF, a biocompatible polymer. In order to obtain the best piezoelectric response