Probing the potential of rare earth elements in the development of new anticancer drugs: single molecule studies

• Josiane A. D. Batista,
• Rayane M. de Oliveira,
• Carlos H. M. Lima,
• Milton L. Lana Júnior,
• Virgílio C. dos Anjos,
• Maria J. V. Bell and
• Márcio S. Rocha

Beilstein J. Nanotechnol. 2025, 16, 187–194, doi:10.3762/bjnano.16.15

• what occurs with classical DNA condensing agents such as polycations and depletants. Keywords: DNA; optical tweezers; rare earth elements; single molecule force spectroscopy; Introduction The development of new drugs to treat human diseases is a field of singular importance that usually involves

• -molecule force spectroscopy using optical tweezers (OT) on DNA complexes formed with the three rare earths at various concentrations. The mechanical properties of these complexes were then determined as a function of the element concentration. From these data, the physical chemistry of the interaction was

• Al-G tips (Budget Sensors). Results and Discussion Force spectroscopy In Figure 1 we show the contour length measured as a function of the ligand concentration for the three types of complexes formed between DNA and the rare earths. For ytterbium and neodymium, this mechanical parameter remains

Advanced atomic force microscopy techniques V

• Philipp Rahe,
• Ilko Bald,
• Nadine Hauptmann,
• Regina Hoffmann-Vogel,
• Harry Mönig and
• Michael Reichling

Beilstein J. Nanotechnol. 2025, 16, 54–56, doi:10.3762/bjnano.16.6

• 10.3762/bjnano.16.6 Keywords: AFM; atomic force microscopy; conductivity; drift correction; force spectroscopy; NC-AFM; non-contact atomic force microscopy; resistivity; tip–surface interaction; With the restrictions on travelling and social distancing lifted, we were delighted to continue two series of

• et al. addresses the significantly increased precision of force spectroscopy measurements when performed with a quartz cantilever allowing to reduce the oscillation amplitude to values in the low picometer regime [2]. As the conversion of frequency-shift to force data critically depends on the

Exploring surface charge dynamics: implications for AFM height measurements in 2D materials

• Mario Navarro-Rodriguez,
• Andres M. Somoza and
• Elisa Palacios-Lidon

Beilstein J. Nanotechnol. 2024, 15, 767–780, doi:10.3762/bjnano.15.64

• capacitance signal was also recorded, as explained in [61]. Spectroscopy data were acquired using a variant of the 3D-mode dynamic force spectroscopy [62], explained in detail in [63]. Briefly, force, frequency shift, amplitude, and phase channels are recorded simultaneously at a fixed sample point as a

Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• similar conclusion was inferred from spatially resolved force spectroscopy across a phthalocyanine molecule on Ag(111) whose pyrrolic H atoms had been removed. Despite the bonds formed by the H-detached N atoms of the molecule with the metal substrate, an increased reactivity was reported [58]. Intact

• evidenced by shifts of the point of maximum attraction and hysteresis loops in force spectroscopy experiments. Scanning tunneling microscopy and spectroscopy of defect types 1 and 2 in graphene on Ir(111). (a) Constant-current STM image of Ar+-bombarded graphene (bias voltage: 100 mV, tunneling current: 50

High–low Kelvin probe force spectroscopy for measuring the interface state density

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

Beilstein J. Nanotechnol. 2023, 14, 175–189, doi:10.3762/bjnano.14.18

• actual semiconductor device evaluation, and there is a need to develop a method for obtaining such physical quantities. Here, we propose high–low Kelvin probe force spectroscopy (high–low KPFS), an electrostatic force spectroscopy method using high- and low-frequency AC bias voltages to measure the

• surfaces to confirm the dependence of the electrostatic force on the frequency of the AC bias voltage and obtain the interface state density. Keywords: high–low Kelvin probe force microscopy; high–low Kelvin probe force spectroscopy; interface state density; Kelvin probe force microscopy; Kelvin probe

• force spectroscopy; Introduction With the recent miniaturization of semiconductor devices, understanding the physical and electrical properties of semiconductor devices, such as the dopant concentration, dopant distribution, and defect level distribution, at the nanoscale has become important. Among

Frequency-dependent nanomechanical profiling for medical diagnosis

• Santiago D. Solares and
• Alexander X. Cartagena-Rivera

Beilstein J. Nanotechnol. 2022, 13, 1483–1489, doi:10.3762/bjnano.13.122

• nanomechanical measurements into medical diagnosis, which includes specialized in vivo sensing, computer analysis (AFM force spectroscopy analysis), communication with the healthcare provider, and mining of the aggregate community database. Given the mechanical nature of AFM, the above strategy naturally fits

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

• interaction force between the particle and the surface. A new colloidal AFM probe was proposed by Daboss et al. [14]. These conductive spherical boron-doped diamond (BDD)-AFM probes allow electrochemical force spectroscopy. The physical robustness of these bifunctional probes and the excellent electrochemical

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

• interfacial energies between a eutectic Ga–In–Sn liquid alloy and single nanoscopic asperities of SiOx, Au, and PtSi have been determined in the temperature range between room temperature and 90 °C by atomic force spectroscopy. For all asperities used here, we find that the interfacial tension of the eutectic

• atomic force microscopy (AFM) tips of different chemistries as a function of the temperature (T = 21–90 °C) by AFM force spectroscopy using an XE100 AFM equipped with a heating stage (manufactured by Park Instruments, Republic of Korea). We recorded force–distance curves with PtSi-coated Si cantilevers

• measurements, each tip was investigated by SEM for possible material transfer from the liquid alloy sample. The values of the half-opening angle θ of the tips were taken from the manufacturer’s data. Table 1 summarizes the properties of the cantilevers used in this work. The force spectroscopy measurements

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

• as The typical value of δf and δV in our measurements were estimated to be 0.1 Hz and 1 mV, respectively, with T = 80 K, Q = 10,000, k = 650 N/m, A = 500 pm, f0 = 910 kHz, fm = 100 Hz, B = 10 Hz, nds = 100 fm/, = 111.25 Hz/V2, and = 1 V. The value of was calculated from Kelvin probe force

• spectroscopy (KPFS) [75][76], as shown in Figure 4. Schematics of AC-KPFM for direct SPV measurements. (a) Block diagram of AC-KPFM in FM mode. FG is a function generator. (b, c) Scheme of the AC bias nullifying method by laser power modulation with (b) sinusoidal and (c) square waveforms, which are

Effects of substrate stiffness on the viscoelasticity and migration of prostate cancer cells examined by atomic force microscopy

• Xiaoqiong Tang,
• Yan Zhang,
• Jiangbing Mao,
• Yuhua Wang,
• Zhenghong Zhang,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2022, 13, 560–569, doi:10.3762/bjnano.13.47

• maintained. An indentation area of 3 μm × 3 μm was selected at the nuclear region where 36 force curves were recorded for each cell in force spectroscopy mode. The indentation force of 1 nN, spring constant values of 0.01 N·m−1, Z length of 5 μm, and an approach speed of approximately 2 μm·s−1 were employed

A new method for obtaining model-free viscoelastic material properties from atomic force microscopy experiments using discrete integral transform techniques

• Berkin Uluutku,
• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2021, 12, 1063–1077, doi:10.3762/bjnano.12.79

• unbounded inputs traditionally used to acquire force–distance relationships in AFM, such as ramp functions, in which the cantilever position is displaced linearly with time for a finite period of time. Keywords: atomic force microscopy; force spectroscopy; material properties; viscoelasticity

•  2), for which we carry out the force analysis in the complex domain (force spectroscopy). Theoretical Background It is well known that the behavior of viscoelastic materials is history-dependent, as a result of which, the stress–strain relationships governing their deformation are functionals (not

• priori. Further research is encouraged on this topic. Conclusion A novel method for obtaining the viscoelastic properties of a material using atomic force spectroscopy has been proposed and demonstrated computationally. The method utilizes Z-transform techniques and yields model-free viscoelastic

Correction: Extracting viscoelastic material parameters using an atomic force microscope and static force spectroscopy

• Cameron H. Parvini,
• M. A. S. R. Saadi and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2021, 12, 137–138, doi:10.3762/bjnano.12.10

• microscopy (AFM); creep; force mapping; indentation; Kelvin–Voigt; static force spectroscopy (SFS); viscoelasticity; In the “Useful Viscoelastic Quantities” section of the original publication, it is stated that the storage modulus (E′) and storage compliance (J′) are inverses of one another (Equation 10

Bulk chemical composition contrast from attractive forces in AFM force spectroscopy

• Dorothee Silbernagl,
• Media Ghasem Zadeh Khorasani,
• Natalia Cano Murillo,
• Anna Maria Elert and
• Heinz Sturm

Beilstein J. Nanotechnol. 2021, 12, 58–71, doi:10.3762/bjnano.12.5

• determined. Keywords: AFM force spectroscopy; composites; principle component analysis; structure–property correlation; van der Waals forces; Introduction The mechanical properties of small volumes of materials can be measured using various atomic force microscopy (AFM) methods. The well-established force

• –distance curve (FDC) method is the most fundamental force spectroscopy experimental setup which yields local mechanical properties with a lateral resolution between 500 nm and 1 µm [1][2][3]. Recent developments have aimed to increase the lateral resolution of force spectroscopy by implementing dynamic

• methods. This has resulted in methods such as force modulation [4], bimodal mode [5], pulsed-force mode [6] or peak force [7], and intermodulation AFM (ImAFM) with amplitude-dependent force spectroscopy (ADFS) [8][9][10]. Dynamic methods record local mechanical properties with a resolution in the range of

On the frequency dependence of viscoelastic material characterization with intermittent-contact dynamic atomic force microscopy: avoiding mischaracterization across large frequency ranges

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 1409–1418, doi:10.3762/bjnano.11.125

• -static force spectroscopy (i.e., using force–distance curves acquired at frequencies much lower than the resonance frequency of the cantilever). Specifically, we have introduced a methodology based on the Generalized Voigt (Kelvin) or Maxwell viscoelastic model (Figure 1), including an arbitrary number

• of dynamic force spectroscopy. First, for samples exhibiting such variation in their moduli, it is not possible to assign a single value to the coefficient of viscous dissipation during deformation, since the loss modulus is not constant. The variation in the elastic modulus also precludes the

Extracting viscoelastic material parameters using an atomic force microscope and static force spectroscopy

• Cameron H. Parvini,
• M. A. S. R. Saadi and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 922–937, doi:10.3762/bjnano.11.77

• materials. AFM static force spectroscopy (SFS) is one approach commonly used in pursuit of this goal. It is capable of acquiring rich temporal insight into the behavior of a sample. During AFM-SFS experiments the cantilever base approaches samples with a nearly constant velocity, which is manipulated to

• microscopy (AFM); creep; force mapping; indentation; Kelvin–Voigt; static force spectroscopy (SFS); viscoelasticity; Introduction Modern AFM applications commonly involve testing samples that are soft, biological, or polymeric in nature. Understanding the dissipative nature of these materials at the

• . While the current approach is primarily geared towards MATLAB implementation, the original process was outlined by Lopez et al. [17] in Python, and is available in a public Github repository. Conditioning raw static force spectroscopy datasets Traditionally, AFM-SFS experiments generate a variety of

Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy

• Christian Ritz,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76

• performed on Δftopo, where all electrostatic forces are compensated, including the static contribution . So far, recovering and fitting the Kelvin parabola is known as an open-loop technique, the so-called Kelvin probe force spectroscopy [22][23][24][25]. A real-time closed-loop technique has not been

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• frequency-modulated atomic force microscopy (AFM). Furthermore, this technique can be extended to the experimental verification of potential forms for any given material pair. Specifically, interaction forces are determined between an AFM tip apex and a nominally flat substrate using dynamic force

• spectroscopy measurements in an ultrahigh vacuum (UHV) environment. The tip geometry, which is initially unknown and potentially irregularly shaped, is determined using transmission electron microscopy (TEM) imaging. It is then used to generate theoretical interaction force–displacement relations, which are

Examination of the relationship between viscoelastic properties and the invasion of ovarian cancer cells by atomic force microscopy

• Mengdan Chen,
• Jinshu Zeng,
• Weiwei Ruan,
• Zhenghong Zhang,
• Yuhua Wang,
• Shusen Xie,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2020, 11, 568–582, doi:10.3762/bjnano.11.45

• , Berlin, Germany) equipped with an inverted optical microscope (Leica, Germany). The viscoelastic properties were investigated in the force spectroscopy working mode. The culture dishes were placed in a Petri dish heater (JPK instrument, Berlin Germany) and maintained at 37 °C during the AFM indentations

Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• given offset, z + offset, using KPFM to measure the CPD. The given offset (100 pm) was applied to avoid the influence of a phantom force [48][49] or induced dipole moments [50]. Force spectroscopy measurements [51] were performed by recording the frequency shift (Δf) as a function of the tip–sample

Mechanical and thermodynamic properties of Aβ₄₂, Aβ₄₀, and α-synuclein fibrils: a coarse-grained method to complement experimental studies

• Adolfo B. Poma,
• Horacio V. Guzman,
• Mai Suan Li and
• Panagiotis E. Theodorakis

Beilstein J. Nanotechnol. 2019, 10, 500–513, doi:10.3762/bjnano.10.51

• ], AFM base-force spectroscopy [51], or by the design of sophisticated microelectromechanical systems (MEMS) [52]. These techniques have been successfully used to predict the elastic properties of several biomolecules. However, OT are limited to applied loads below 0.1 nN and AFM has delicate calibration

Nitrous oxide as an effective AFM tip functionalization: a comparative study

• Taras Chutora,
• Bruno de la Torre,
• Pingo Mutombo,
• Jack Hellerstedt,
• Jaromír Kopeček,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2019, 10, 315–321, doi:10.3762/bjnano.10.30

• spectroscopy measurements, i.e., the interaction energy toward different atomic species in force spectroscopy, the contact potential difference in Kelvin probe force microscopy (KPFM) [9][29] and vibrational levels of inelastic tunneling spectroscopy (IETS) [30][31]. A particular termination of the tip may be

Scanning probe microscopy for energy-related materials

• Rüdiger Berger,
• Benjamin Grévin,
• Philippe Leclère and
• Yi Zhang

Beilstein J. Nanotechnol. 2019, 10, 132–134, doi:10.3762/bjnano.10.12

• the local dielectric distribution based on surface adhesion mapping by SPM [11]. This method is evidently easy in terms of operation and thus has the potential to be widely used. Finally, we want to highlight the contribution “Electrostatic force spectroscopy revealing the degree of reduction of

• individual graphene oxide sheets” by Yue Shen and co-workers. Yue Shen won the prize for the best presentation during the E-MRS conference [12]. Electrostatic force spectroscopy (EFS) is used here to characterize the degree of reduction of uniformly reduced one-atom-thick graphene oxide (GO) sheets at the

In situ characterization of nanoscale contaminations adsorbed in air using atomic force microscopy

• Jesús S. Lacasa,
• Lisa Almonte and
• Jaime Colchero

Beilstein J. Nanotechnol. 2018, 9, 2925–2935, doi:10.3762/bjnano.9.271

• to access the state of contamination of real surfaces under ambient conditions using advanced atomic force microscopy techniques. Keywords: atomic force microscopy; cantilever; contact potential; electrostatic forces; force spectroscopy; Hamaker constant; Kelvin probe microscopy; surface

Electrostatic force spectroscopy revealing the degree of reduction of individual graphene oxide sheets

• Yue Shen,
• Ying Wang,
• Yuan Zhou,
• Chunxi Hai,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 1146–1155, doi:10.3762/bjnano.9.106

• Province, Xining 810008, China Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China 10.3762/bjnano.9.106 Abstract Electrostatic force spectroscopy (EFS) is a method for monitoring the electrostatic force microscopy

• ; electrostatic force microscopy; electrostatic force spectroscopy; graphene oxide; Introduction Graphene is a two dimensional (2D) crystal with superior mechanical [1], thermal [2], electrical [3][4] and optical [5] properties. It can be produced using graphene oxide (GO) as a precursor through cost-effective

• reduced with different methods. Although the reduction process of GO sheets has been studied with EFM, little attention has been paid to the use of electrostatic force spectroscopy (EFS) to reveal uniformly reduced GO sheets with various degree of reduction. Previously, EFS was proposed to distinguish

Dry adhesives from carbon nanofibers grown in an open ethanol flame

• Christian Lutz,
• Julia Syurik,
• C. N. Shyam Kumar,
• Christian Kübel,
• Michael Bruns and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271

• fabricated arrays of carbon nanofibers with different degrees of orientation. Inspired by the dry adhesive system of geckos we investigated the adhesive properties of such carbon nanofiber arrays with ordered and random orientation. AFM-based force spectroscopy revealed that adhesion force and energy rise