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Typical scan patterns used in AFM: (a) raster scan path used by Nanosurf (b) zigzag scan path used by Veeco. Top view: the grey disk corresponds to the position of the tip on the surface and the yellow, blue and red disks are the positions of spherical particles pushed by the tip along its scan path.
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One key component in the assembly of nanoparticles is their precise positioning to enable the creation of new complex nano-objects. Controlling the nanoscale interactions is crucial for the prediction and understanding of the behaviour of nanoparticles (NPs) during their assembly. In the present work, we have manipulated bare and functionalized gol...
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... this obser- vation it is possible to fractionate and separate small from big particles adsorbed on a substrate. This size-dependence of the particle trajectory was explained by a simulation which shows that the trajectory of the particle at the same time depends on i) the operating parameter which is the scanning path used by AFM (zigzag or scattered one, Figure 3), ii) the density of scan lines and, iii) the parameter R tot which corresponds to the sum of the radii of the tip and the particle [39]. ...
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... Cancer is the most prevailing medical problem globally, and according to a recent report by World Health Organization (WHO), cancer is reported as second major cause of death after ischemic heart disease [100]. The major cancer types in many countries are breast, lung, prostrate, ovarian, and rectum, and they have been reported as the cause of death for nearly 10 million people worldwide in 2020 [101,102]. ...
Metallic nanoparticles (MNPs) have been used for the treatment of aliments since ancient times, and they have been reported for their medicinal properties in recent years. This chapter discusses the synthesis and characterization of MNPs and their potential applications in targeted drug delivery as well as genetic manifestation. It also elaborates on its implications for cell therapy and the outcome of the clinical trial under way. By using MNP, targeted delivery to the tumor cells can be achieved by using any of the strategies such as passive targeting, active targeting, and magnetic targeting. Genetic manipulations are gene editing techniques that permit the genome to target specific locations for deletion, addition, or substitution. This can be done for both germinal and somatic genes. The improvement in the practical potential of metallic nanoparticles emphasizes their potency as novel tools for drug delivery therapeutic modalities, particularly in the treatment of cancer, inflammation, diabetes, and antiviral therapy. Metallic nanoparticle development is quick and multidirectional.
... In these images, it was possible to observe individual spherical nanoparticles and their aggregates. The average diameter of the AuNPs measured from the images was approximately 11-19 nm [48,49]. ...
In this study, gold nanoparticles (AuNPs) were synthesized using the Turkevich method. This article explains the didactic step-by-step synthesis, showing pictures of the entire process, including a well-explained mechanism and characterization study. Synthesis involves the reduction of NaAuCl4 using sodium citrate at high temperatures (approximately 90 °C). The two main mechanisms used to explain AuNPs synthesis via the Turkevich method are also discussed. The first mechanism considers that a nanowire intermediary and the other proposes that aggregate intermediates are not formed at any time during the synthesis. The materials (NaAuCl4 and AuNPs) were characterized using UV-Vis spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and dynamic light scattering (DLS). The UV-Vis spectrum exhibits an absorption maximum at 521 nm because of the surface plasmon resonance (SPR) absorption band of the AuNPs. The SEM images of NaAuCl4 show crystals with cubic shapes, while the AuNPs have an average particle size of approximately 16–25 nm and particles that appear mainly spherical. To confirm the particle shapes, AFM was conducted, and it was possible to clearly observe individual spherical nanoparticles and their aggregates, and the average diameter of these AuNPs was approximately 12–19 nm. The XRD pattern of AuNPs showed four main characteristic peaks corresponding to the (111), (200), (220), and (311) planes, confirming the presence of cubic (FCC) gold. The DLS presented an average particle size of 3.3 ± 0.9 nm and a polydispersity index (PDI) of 0.574. AuNPs were synthesized using a simple and rapid method. The resulting spherical and ultra-small particles can be used in several applications.
... In the images it is possible to observe clearly the individual spherical nanoparticles and their aggregates. The average diameter of these AuNPs measured by the image was around 11 -19 nm [48,49]. 8 of 15 The results are in agreement with the SEM images. ...
The gold nanoparticle (AuNP) was synthesized using the well-known Turkevich method. This article explains didactic step-by-step of the synthesis, showing pictures of the entire process, including a well-explained mechanism and characterization study. The synthesis includes the reduction of NaAuCl4 using sodium citrate in high temperature (around 90 ⁰C). The two main mechanisms used to explain the AuNP synthesis via Turkevich method were explained. The first mechanism considerate that a nanowire intermediary and the other proposed that aggregate intermediates are not formed at any time during the synthesis. The materials (NaAuCl4 and AuNP) were characterized by UV-Vis, SEM, AFM, XRD and DLS. The UV-Vis exhibit an absorption maximum in 521 nm because the surface plasmon resonance (SPR) absorption band of AuNP. The SEM images of NaAuCl4 presents crystals with cubic shapes, while the AuNP presents average particle size of about 16-25 nm and particles that appear mainly spherical. To confirm the particles shapes, the AFM was conducted and it was possible to observe clearly the individual spherical nanoparticles. The XRD of AuNP showed the four main characteristic peaks for silver corresponding to (111), (200), (220) and (311) planes, confirming the cubic (FCC) silver. The DLS presented the average particle size of 3.3 ± 0.9 nm and the polydispersity index (PDI) of 0.574. In summary, the AuNP was synthesized using a simple and fast method. The result was a spherical and ultrasmall particle, that can be used is several applications.
... By examining the interaction between the cantilever tip and the sample surface, AFM generates the exact morphological structure of the samples. This characterization method is complementary to SEM and HRTEM techniques [144]. These techniques allow us to analyze and characterize the samples from a few micrometers to nanometer-scale levels. ...
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... Recently, photocatalysis is found to be one of the best alternative processes for water decontamination as compared to other physical, chemical, biological and sludge methods (Castello 2009(Castello ). et al. 2014Rao et al. 2007;Darwich et al. 2011) like scanning electron microscopy (SEM) with EDX accessory (Khanna et al. 2019;Lapresta-Fernández et al. 2014), transmission electron microscopy (TEM) (Allec et al. 2015;Goel and Arora 2018, 2020aKhanna et al. 2019;Lapresta-Fernández et al. 2014;Rao et al. 2007;Darwich et al. 2011), high-resolution transmission electron microscopy (HRTEM) (Khanna et al. 2019), and atomic force microscopy (AFM) (Rao et al. 2007;Darwich et al. 2011), dynamic light scattering (DLS) (Jans et al. 2009), visual colorimetry (Ramalingam 2019), UV-Visible spectroscopy (UV-Vis) technique in 500-900 nm region (Goel and Arora 2018, 2020aRoduner 2006;Ray et al. 2015;Shukla and Iravani 2017;Amendola et al. 2017;Zuber et al. 2016), Mass spectroscopy (MS) (Harkness et al. 2010), Inductively coupled plasma-mass spectrometry (ICP -MS) (Trapiella-Alfonso et al. 2014), Nuclear magnetic resonance (NMR) (Guo and Yarger 2018) techniques to confirm their formation, particle size, shape, morphology and degradation/mineralization reaction products. ...
... Recently, photocatalysis is found to be one of the best alternative processes for water decontamination as compared to other physical, chemical, biological and sludge methods (Castello 2009(Castello ). et al. 2014Rao et al. 2007;Darwich et al. 2011) like scanning electron microscopy (SEM) with EDX accessory (Khanna et al. 2019;Lapresta-Fernández et al. 2014), transmission electron microscopy (TEM) (Allec et al. 2015;Goel and Arora 2018, 2020aKhanna et al. 2019;Lapresta-Fernández et al. 2014;Rao et al. 2007;Darwich et al. 2011), high-resolution transmission electron microscopy (HRTEM) (Khanna et al. 2019), and atomic force microscopy (AFM) (Rao et al. 2007;Darwich et al. 2011), dynamic light scattering (DLS) (Jans et al. 2009), visual colorimetry (Ramalingam 2019), UV-Visible spectroscopy (UV-Vis) technique in 500-900 nm region (Goel and Arora 2018, 2020aRoduner 2006;Ray et al. 2015;Shukla and Iravani 2017;Amendola et al. 2017;Zuber et al. 2016), Mass spectroscopy (MS) (Harkness et al. 2010), Inductively coupled plasma-mass spectrometry (ICP -MS) (Trapiella-Alfonso et al. 2014), Nuclear magnetic resonance (NMR) (Guo and Yarger 2018) techniques to confirm their formation, particle size, shape, morphology and degradation/mineralization reaction products. ...
... Recently, photocatalysis is found to be one of the best alternative processes for water decontamination as compared to other physical, chemical, biological and sludge methods (Castello 2009(Castello ). et al. 2014Rao et al. 2007;Darwich et al. 2011) like scanning electron microscopy (SEM) with EDX accessory (Khanna et al. 2019;Lapresta-Fernández et al. 2014), transmission electron microscopy (TEM) (Allec et al. 2015;Goel and Arora 2018, 2020aKhanna et al. 2019;Lapresta-Fernández et al. 2014;Rao et al. 2007;Darwich et al. 2011), high-resolution transmission electron microscopy (HRTEM) (Khanna et al. 2019), and atomic force microscopy (AFM) (Rao et al. 2007;Darwich et al. 2011), dynamic light scattering (DLS) (Jans et al. 2009), visual colorimetry (Ramalingam 2019), UV-Visible spectroscopy (UV-Vis) technique in 500-900 nm region (Goel and Arora 2018, 2020aRoduner 2006;Ray et al. 2015;Shukla and Iravani 2017;Amendola et al. 2017;Zuber et al. 2016), Mass spectroscopy (MS) (Harkness et al. 2010), Inductively coupled plasma-mass spectrometry (ICP -MS) (Trapiella-Alfonso et al. 2014), Nuclear magnetic resonance (NMR) (Guo and Yarger 2018) techniques to confirm their formation, particle size, shape, morphology and degradation/mineralization reaction products. ...
Biochar-based nanomaterials have shown unbelievable prospective in managing various environmental contaminations and display immense enhancement in functional groups, surface active sites, pore size properties, catalytic degradation properties, etc. Their applications gaining increase interest due to the simplicity of preparation methods and their enhanced physicochemical properties. Therefore, the development of such nanomaterials has targeted in various research objectives including water/wastewater treatment, soil remediation, agriculture, and pollution. Sorption, catalysis, redox reaction and other structural and functional properties of biochar showed the alteration or removal of contaminations from the environment and are considered as incredible efficient ways in handling various challenging environmental issues. Considering the quick expansion of biochar-based nanomaterials. This chapter will serve the helpful information to summarize the various applications of this magical material in environmental cleanup, along with wastewater treatment, soil remediation, and agriculture advancement. In addition, synthesizing such efficient nanoparticles will provide a novel approach against various environmental concern and promise vast applications of nanotechnology.KeywordsBiocharNanomaterialWastewater treatmentSoil remediationAgriculture advancement
... Hsieh et al. manipulated individual Au nanorods by scanning electron microscopy (SEM) [11]. To investigate the effects of the size, shape, and grafting of gold nanoparticles, as well as the morphology of the substrate surface during manipulation, Samer et al. studied the dynamic behavior of bare and thiol group-coated gold nanoparticles while manipulating them on different surfaces by atomic force microscopy (AFM) [12]. However, the adhesion of particles to the surface of a substrate [13][14][15] is affected to varying degrees by the AFM probe tip structure [16][17][18], the manipulation environment [19,20], and the way the nanoparticles are manipulated (e.g., pushing, gathering) [2,21]. ...
In the manipulation of nanoparticles for precise placement, the relatively low adhesion of the nanoparticles to the substrate surface has emerged as a problem. Owing to the fact that nanoparticles manipulated using atomic force microscopy (AFM) often cannot be accurately placed at their predetermined destinations or may even go astray, becoming “lost,” the success rate of manipulation attempts is low. We investigated the possibility of enhancing the adhesion between magnetic nanoparticles and a substrate surface by modifying a mica substrate with a solution of 3-aminopropyltriethoxysilane (APTES). The morphology of the mica surface before and after modification was analyzed, and the adhesive force was calculated by using AFM in contact mode. The effect of different APTES-solution concentrations on the adhesive force was analyzed as well. The results demonstrate that the adhesion of the nanoparticles to the modified substrate was substantially stronger than their adhesion to an unmodified surface, a finding that can be used to improve the success rate of nanoparticle manipulation.
... Later on, the manipulation operations were investigated in the semi-contact AFM mode combined with the lateral pushing technique [17,[21][22][23][24][25][26]. This made it possible to control the position of the particle at the moments of its interaction with the tip, which simplified the task of precise moving the particle to the given position. ...
... In [11, 33-36], particle displacement due to lateral pushing was used to determine the friction forces at the nanoscale. Other papers [17,[21][22][23][24][25][26] were devoted to controlled displacement of nanoobjects on the surface (spherical Au particles were used with diameters of 5-70 nm). In these works, as in our case, the displacement process was accompanied by the appearance of nanotracks in AFM images, which made it possible to analyze the influence of various factors on the particle trajectory. ...
... In such cases, one of the particles blocks the movement of the others (see nanotracks 3a-c→3′ in figure 3(b)), or several NPs can be combined into a new aggregate which will continue to move as a whole (see nanotrack 4→4′ in figure 3(b)). Also, some curvature of the particle's trajectory can be due to its complex geometric shape and hence, under the impacts of lateral pushes, the particle performs not only translational, but also some rotational motion [24,37]. ...
Atomic force microscopy (AFM) is widely used for structural characterization of 2D materials.We
report here on the appearance of linear pseudo-structures of subnanometer height (‘nanotracks’),
observed inAFMimages of 2D-nanoparticles of graphene, MoS2,WS2, BN, synthesized by the
mechanochemical technique and deposited from dispersions on the mica surface. It is stated that the
nanotracks appear as a result of nanoparticle displacement on the surface under the influence of the
AFMtip during scanning. The appearance of the nanotracks is caused by a high relative concentration
of monolayer nanoparticles in the prepared dispersions; their bulk aggregation; subsequent
destruction of the aggregates by theAFMprobe with formation of the nanoparticles weakly bound to
the substrate. A method is proposed how to distinguish monolithic particles from granulated
aggregates, as well as a technique to prevent their displacement during measurements. The possibility
is considered of usingAFMto develop effective nanolubricants and provide their precise nanoscale
deposition on the specified surface areas.
... In one study, the friction force of a ZnO nanowire with a mass of about 18.7 ng placed horizontally on a Si wafer was calculated in the range of 36.4 to 69.3 nN, which corresponded to extremely high friction coefficients of 242 and 462, respectively (Kim et al., 2013). In addition to ZnO nanowires, SiO nanowire (Tran & Chung, 2015), single polystyrene (Guo et al., 2013), cadmium selenide nanorod (Tranvouez et al., 2009), carbon nanotubes (Falvo et al., 1998), living cells (You & Yu, 1999), gold nanoparticles (Darwich et al., 2011), single crystalline , SiC nanowires (Xie et al., 2018), and so on can be used as other laboratory samples to calculate the frictional force. ...
In this article, the collection of studies with regard to the modeling of nanomanipulation based on atomic force microscope (AFM) is discussed. To model the manipulation process, two-dimensional and three-dimensional models in the classical environment and molecular dynamics can be presented. The decisive factor in determining the solution’s type depends on the dimensions and application of manipulation. In general, however, benefiting from multiscale methods offers more realistic results from the inherent characteristics of AFM point of view. In addition, the manipulation process is examined empirically. Different parameters affect the process. Overall, these include the geometric properties of AFM, geometric properties and material of nanoparticles, process execution environment, initial impact of nanoparticles, contact mechanics, and roughness. The geometric parameters of AFM have less importance compared with other factors. The material and geometry of nanoparticles and environmental reaction play their most dominant role in contact and roughness equations as well as intermolecular forces. For instance, for softer nanoparticles, elastoplastic and viscoelastic contact theories are more suited. In contrast, in environments except vacuum and air, roughness models with more developed adhesion terms are better choices. Employing complex contact theories can provide us with permanent deformations, roughness, reduction in force, and critical indentation depth. In addition to the involved parameters in modeling the nanomanipulation process, path planning techniques for obtaining the optimal path and control of the AFM set for its exact execution are other influential notions.
... The small size and the enhanced properties of Au nanoparticles (NPs) compared to bulk gold make them important for the development of novel applications, for example, in the field of drug delivery [1], sensor technology [2], printing [3] and catalysis [4]. Due to their inert state, geometrical diversity and convenient synthesis, Au NPs are an attractive model system for nanotribological manipulation experiments [5][6][7][8][9][10][11][12] and simulations [13]. Additional flexibility is provided by the ability to tune the properties of the NPs by varying the size [14] , shape [14] and chemical composition of the outer layer covering the NP [5]. ...
... Darwich and co-workers [8]. They studied the rolling and sliding motion of NPs as a function of NP size and showed that the dissipated power necessary for sliding has little or no dependence on the NP radius, while the dissipated power needed to provoke rolling decreased clearly with increasing NP radius. ...
In the present paper, we investigate the effect of heat treatment on the geometry and mobility of Au nanoparticles (NPs) on a Si substrate. Chemically synthesized Au NPs of diameter ranging from 5 to 27 nm were annealed at 200, 400, 600 and 800 °C for 1 h. A change in the geometry from faceted to more rounded shapes were observed with increasing annealing temperature. Kinetic Monte Carlo simulations indicate that the NPs become rounded due to the minimization of the surface area and the transition to lower energy surface types {111} and {100}. The NPs were manipulated on a silica substrate with an atomic force microscope (AFM) in tapping mode. Initially, the NPs were immovable by AFM energy dissipation. However, annealed NPs became movable, and less energy was required to displace the NPs annealed at higher temperature. However, after annealing at 800 °C, the particles became immovable again. This effect was attributed to the diffusion of Au into the Si substrate and to the growth of the SiO 2 layer.
... The AFM was applied to characterize the morphology, single AuNP profile, and the particle size distribution (PSD) of AuNPs functionalized by selected gold(III) complexes [45,46]. The results obtained for naked NPs clearly show that the isolated AuNP is spherical in shape with an overall particle size of 34 ± 5 nm ( Figure 3). ...
Citrate-capped gold nanoparticles (AuNPs) were functionalized with three distinct antitumor gold(III) complexes, e.g., [Au(N,N)(OH)2][PF6], where (N,N)=2,2'-bipyridine; [Au(C,N)(AcO)2], where (C,N)=deprotonated 6-(1,1-dimethylbenzyl)-pyridine; [Au(C,N,N)(OH)][PF6], where (C,N,N)=deprotonated 6-(1,1-dimethylbenzyl)-2,2'-bipyridine, to assess the chance of tracking their subcellular distribution by atomic force microscopy (AFM), and surface enhanced Raman spectroscopy (SERS) techniques. An extensive physicochemical characterization of the formed conjugates was, thus, carried out by applying a variety of methods (density functional theory-DFT, UV/Vis spectrophotometry, AFM, Raman spectroscopy, and SERS). The resulting gold(III) complexes/AuNPs conjugates turned out to be pretty stable. Interestingly, they exhibited a dramatically increased resonance intensity in the Raman spectra induced by AuNPs. For testing the use of the functionalized AuNPs for biosensing, their distribution in the nuclear, cytosolic, and membrane cell fractions obtained from human lymphocytes was investigated by AFM and SERS. The conjugates were detected in the membrane and nuclear cell fractions but not in the cytosol. The AFM method confirmed that conjugates induced changes in the morphology and nanostructure of the membrane and nuclear fractions. The obtained results point out that the conjugates formed between AuNPs and gold(III) complexes may be used as a tool for tracking metallodrug distribution in the different cell fractions.
