Generalized Hertz model for bimodal nanomechanical mapping

• Aleksander Labuda,
• Marta Kocuń,
• Waiman Meinhold,
• Deron Walters and
• Roger Proksch

Beilstein J. Nanotechnol. 2016, 7, 970–982, doi:10.3762/bjnano.7.89

• a Ti/Ir-coated tip of nominal tip radius R = 28 ± 10 nm. Photothermal excitation [56] was used, which ensures stable imaging [57] and accurate FM tracking [58][59][60]. An automated calibration method [61] was used to obtain the stiffness of the first eigenmode (kc1 = 43.2 N/m), which was then used

Noncontact atomic force microscopy III

• Mehmet Z. Baykara and
• Udo D. Schwarz

Beilstein J. Nanotechnol. 2016, 7, 946–947, doi:10.3762/bjnano.7.86

• particular, latest instrumental advances are highlighted in the form of a new design for a large-area SPM used for electrostatic force measurements, improvement of dynamic cantilever response by the utilization of reflective coatings and photothermal conversion layers, and the use of length extension

Efficiency improvement in the cantilever photothermal excitation method using a photothermal conversion layer

• Natsumi Inada,
• Hitoshi Asakawa,
• Taiki Kobayashi and
• Takeshi Fukuma

Beilstein J. Nanotechnol. 2016, 7, 409–417, doi:10.3762/bjnano.7.36

• /bjnano.7.36 Abstract Photothermal excitation is a cantilever excitation method that enables stable and accurate operation for dynamic-mode AFM measurements. However, the low excitation efficiency of the method has often limited its application in practical studies. In this study, we propose a method for

• improving the photothermal excitation efficiency by coating cantilever backside surface near its fixed end with colloidal graphite as a photothermal conversion (PTC) layer. The excitation efficiency for a standard cantilever of PPP-NCHAuD with a spring constant of ≈40 N/m and a relatively stiff cantilever

• than 2 h without any indication of possible contamination from the coating. The proposed method, using a PTC layer made of colloidal graphite, greatly enhances photothermal excitation efficiency even for a relatively stiff cantilever in liquid. Keywords: atomic force microscopy; cantilever excitation

High-bandwidth multimode self-sensing in bimodal atomic force microscopy

• Michael G. Ruppert and
• S. O. Reza Moheimani

Beilstein J. Nanotechnol. 2016, 7, 284–295, doi:10.3762/bjnano.7.26

• . To circumvent this problem, integrated actuation such as magnetic [4], photothermal [5], resistive thermal [6], ultrasonic [7] or through a piezoelectric layer [8] have been employed. Among the sensing techniques to detect the cantilever oscillations, the optical beam deflection (OBD) method [9

Self-organization of gold nanoparticles on silanated surfaces

• Htet H. Kyaw,
• Salim H. Al-Harthi,
• Azzouz Sellai and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2015, 6, 2345–2353, doi:10.3762/bjnano.6.242

• photothermal therapy [16]. AuNPs exhibit well-defined optical properties such as surface plasmon resonance, which depends on the size and shape of nanoparticles, interparticle distance and the effective refractive index of the surrounding medium [17]. Different techniques have been used to assemble AuNPs on

Improved atomic force microscopy cantilever performance by partial reflective coating

• Zeno Schumacher,
• Yoichi Miyahara,
• Laure Aeschimann and
• Peter Grütter

Beilstein J. Nanotechnol. 2015, 6, 1450–1456, doi:10.3762/bjnano.6.150

• reduction is due to the reduced photothermal (bimetallic) effect. Note that the sharp peaks in the spectra are of electronic origin as they also appear in the detection noise. We observed the similar reduction in 1/f noise for the NCLR cantilevers, which can be seen in Supporting Information File 1, Figure

Low-cost formation of bulk and localized polymer-derived carbon nanodomains from polydimethylsiloxane

• Juan Carlos Castro Alcántara,
• Mariana Cerda Zorrilla,
• Lucia Cabriales,
• Luis Manuel León Rossano and
• Mathieu Hautefeuille

Beilstein J. Nanotechnol. 2015, 6, 744–748, doi:10.3762/bjnano.6.76

• reported in [20]. The nanoresidues also show good photothermal stability as the intensity of the fluorescence emission did not present quenching after hours of irradiation under a fluorescence microscope or when characterized with a 4 W UV lamp and characterized with a photomultiplier tube, even months

A scanning probe microscope for magnetoresistive cantilevers utilizing a nested scanner design for large-area scans

• Tobias Meier,
• Alexander Förste,
• Ali Tavassolizadeh,
• Karsten Rott,
• Dirk Meyners,
• Roland Gröger,
• Günter Reiss,
• Eckhard Quandt,
• Thomas Schimmel and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2015, 6, 451–461, doi:10.3762/bjnano.6.46

• , optical read-outs have to be readjusted not only after every cantilever exchange but also after temperature drifts which can offset the focal position of the laser and photo-detector due to thermal expansion. Additionally, the optical read-out can influence the cantilevers deflection by photothermal

Influence of spurious resonances on the interaction force in dynamic AFM

• Luca Costa and
• Mario S. Rodrigues

Beilstein J. Nanotechnol. 2015, 6, 420–427, doi:10.3762/bjnano.6.42

• piezoelectric excitation. In particular, in the last decade magnetic [8][9], capacitive [10] and photothermal [11][12] actuation schemes have been introduced. The differences between the direct excitation of the tip and the conventional dither excitation have already been studied and reported [13][14

Mechanical properties of MDCK II cells exposed to gold nanorods

• Anna Pietuch,
• Bastian Rouven Brückner,
• David Schneider,
• Marco Tarantola,
• Christina Rosman,
• Carsten Sönnichsen and
• Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21

• membrane rendering them prime candidates for multifunctional carriers [6][7][8]. Potential applications encompass selective drug delivery, photothermal therapy, reporters for biosensors and the use as contrast agents [5][9]. Targets can be addressed specifically by functionalization of the particle surface

Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating

• Christina Rosman,
• Sebastien Pierrat,
• Marco Tarantola,
• David Schneider,
• Eva Sunnick,
• Andreas Janshoff and
• Carsten Sönnichsen

Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257

• tools for photothermal therapy [2][10]. However, the impact of functionalized nanomaterials on living organisms is still not fully understood and the number of studies on this topic are few compared to the number of nanoparticle types and applications [11]. To date, the studies are focused on

High-frequency multimodal atomic force microscopy

• Adrian P. Nievergelt,
• Jonathan D. Adams,
• Pascal D. Odermatt and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2014, 5, 2459–2467, doi:10.3762/bjnano.5.255

• bandwidth of 20 MHz, enabling multifrequency techniques extended beyond 2 MHz for obtaining materials contrast in liquid and air, as well as soft imaging of delicate biological samples. Keywords: atomic force microscopy; multifrequency imaging; nanomechanical characterization; photothermal excitation

• including magnetic [20], resistive thermal [21], integrated piezotransducer [22] or photothermal [23][24] excitation, eliminating this effect. Of the direct drive techniques, photothermal-based excitation has the benefit that it is compatible with most standard AFM cantilevers and, although long-established

• , has recently gained renewed interest [25][26][27][28][29][30]. Although the efficiency of photothermal excitation varies with different coatings, even uncoated cantilevers have been shown to work [31]. Furthermore, photodiode readout electronics in the OBD system typically have been restricted to

Hybrid spin-crossover nanostructures

• Carlos M. Quintero,
• Gautier Félix,
• Iurii Suleimanov,
• José Sánchez Costa,
• Gábor Molnár,
• Lionel Salmon,
• William Nicolazzi and
• Azzedine Bousseksou

Beilstein J. Nanotechnol. 2014, 5, 2230–2239, doi:10.3762/bjnano.5.232

• silica sources, respectively. The SCO nano-composite particles were combined with gold NPs with the aim of using the properties of the gold to absorb light and convert it to heat (via a strong photothermal effect). Despite the small volume fraction of gold NPs within the nanocomposite (around 0.5%), the

• . Furthermore, the spin-state switching behavior was also observed due to plasmonic heating. Such devices that display synergy between plasmon resonance and molecular spin states may be of great interest for implementing detection or self-regulation strategies on-chip for the photothermal effect or, with an

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

• Katarzyna Grochowska,
• Katarzyna Siuzdak,
• Peter A. Atanasov,
• Carla Bittencourt,
• Anna Dikovska,
• Nikolay N. Nedyalkov and
• Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

• the particle shape variations which range from partially spherical to cup-like to partial spheroids. Nanostructuring via the photothermal effect associated with strong plasmonic absorption (i.e., collective oscillation of the free electrons between the metal and dielectric when excited around the

• resonant frequency) was reported by Hubenthal and coworkers who obtained controlled rearrangement of the NP population and morphology using laser pulses of energy tunable in the range of 0.7–4 eV (1771–310 nm) [13]. For thin, granular Au films, the photothermal effect at a wavelength corresponding to the

• laser pulses of duration longer than 50 ps, the interaction effect is photothermal in nature, while for shorter pulses, the ballistic energy transfer dominates [22][23]. In a recent paper on the nanosecond laser effect, Kneier et al. reported time-resolved data from interferometric measurements and

Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2014, 5, 1849–1863, doi:10.3762/bjnano.5.196

• size of the nanomaterial itself [87][88][89], as well as on the presence of metal contaminants and the residues of the GO preparation method in graphene samples [90]. Biomedical applications of graphene and its derivatives range from photothermal tumour ablation therapy to biosensors, from gene therapy

• near-infrared region as a photothermal agent for in vivo cancer treatment, while scrutinising the effects originating from different graphene sizes and coatings [97]. Several research groups have focused on graphene as biosensors. Dey et al. [98] developed an amperometric cholesterol biosensor; Tang

In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?

• Moritz Nazarenus,
• Qian Zhang,
• Mahmoud G. Soliman,
• Pablo del Pino,
• Beatriz Pelaz,
• Susana Carregal-Romero,
• Joanna Rejman,
• Barbara Rothen-Rutishauser,
• Martin J. D. Clift,
• Reinhard Zellner,
• G. Ulrich Nienhaus,
• James B. Delehanty,
• Igor L. Medintz and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161

• fluorescence. b) After release of the pH-sensitive fluorophore linked to dextran to the cytosol (by photothermal heating), the fluorophore–dextran conjugates are freely dispersed, without any visible granular structure. Due to the neutral pH in the cytosol the fluorescence of the fluorophore–dextran conjugates

In vitro toxicity and bioimaging studies of gold nanorods formulations coated with biofunctional thiol-PEG molecules and Pluronic block copolymers

• Tianxun Gong,
• Douglas Goh,
• Malini Olivo and
• Ken-Tye Yong

Beilstein J. Nanotechnol. 2014, 5, 546–553, doi:10.3762/bjnano.5.64

• the NIR region so that heat is generated to damage cells and tissues. This property renders them useful for photothermal therapy and imaging of cancer [7][8]. In addition, the AuNRs surface can be functionalized with ligands for targeted drug delivery to support cancer therapy in vitro and in vivo [9

Near-infrared dye loaded polymeric nanoparticles for cancer imaging and therapy and cellular response after laser-induced heating

• Tingjun Lei,
• Alicia Fernandez-Fernandez,
• Romila Manchanda,
• Yen-Chih Huang and
• Anthony J. McGoron

Beilstein J. Nanotechnol. 2014, 5, 313–322, doi:10.3762/bjnano.5.35

• (wavelength 700–900 nm) are promising for in vivo imaging because light at these wavelengths has minimal absorption by tissue [6][7]. Moreover, some NIR dyes such as indocyanine green (ICG) can be used as both imaging agents and heat generators due to their unique photothermal properties. However, ICG has a

• , which normalizes the thermal dose to cumulative equivalent minutes at 43 °C [26], the temperature and the duration of heating can be used to define thermal damage. Our previous paper and other groups’ reports indicate that the rate of photothermal treatment might also affect the HT outcome, because

Peak forces and lateral resolution in amplitude modulation force microscopy in liquid

• Horacio V. Guzman and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2013, 4, 852–859, doi:10.3762/bjnano.4.96

• low Q are valid for directly excited cantilevers, such as magnetic [41][42][43] or photothermal excitations [44][45]. The tip–sample interaction forces are modelled by using two different contact mechanics models, Hertz [29] and Tatara [30][31][32]. The widely used Hertz model gives the force as The

Substrate-mediated effects in photothermal patterning of alkanethiol self-assembled monolayers with microfocused continuous-wave lasers

• Anja Schröter,
• Mark Kalus and
• Nils Hartmann

Beilstein J. Nanotechnol. 2012, 3, 65–74, doi:10.3762/bjnano.3.8

• been demonstrated to provide promising new approaches to nonlinear laser processing. Most notably, because of their ultrathin nature, indirect excitation mechanisms can be exploited in order to fabricate subwavelength structures. In photothermal processing, for example, microfocused lasers are used to

• continuous-wave lasers. The lateral resolution, generally, depends on both the type of the organic monolayer and the nature of the substrate. In previous studies we reported on photothermal patterning of distinct types of SAMs on Si supports. In this contribution, a systematic study on the impact of the

• substrate on the overall patterning process and provide new perspectives in photothermal laser patterning of ultrathin organic coatings. Keywords: femtosecond lasers; nonlinear laser processing; self-assembled monolayers; subwavelength patterning; ultrathin resists; Introduction In the past decades, self