DNA–melamine hybrid molecules: from self-assembly to nanostructures

• Rina Kumari,
• Shib Shankar Banerjee,
• Anil K. Bhowmick and
• Prolay Das

Beilstein J. Nanotechnol. 2015, 6, 1432–1438, doi:10.3762/bjnano.6.148

• molecules can result in unique DNA-based nanostructures for application in molecular and cellular biophysics, as biomimetic systems, in energy transfer and photonics, and in diagnostics and therapeutics [18][19][20][21]. Moreover, as a bottom-up technique, such a methodology can contribute to molecular

Natural and artificial binders of polyriboadenylic acid and their effect on RNA structure

• Giovanni N. Roviello,
• Domenica Musumeci,
• Valentina Roviello,
• Marina Pirtskhalava,
• Alexander Egoyan and
• Merab Mirtskhulava

Beilstein J. Nanotechnol. 2015, 6, 1338–1347, doi:10.3762/bjnano.6.138

• affinity constant of about 104 M−1, (b) a remarkable energy transfer from adenine base pairs to the ligand, as well as (c) a significant conformational variation of the poly(rA) duplex. Calorimetry studies evidenced an exothermic- and enthalpy-driven binding of sanguinarine to double helical poly(rA) in

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• network when nanotubes are semiconducting. Keywords: composite; conjugated polymer; DFT calculations; energy transfer; photoconductivity; single wall carbon nanotubes; time-resolved photoluminescence; Introduction Electroactive conjugated polymers (ECPs) are technologically promising for organic light

• photoexcitation. The efficiency of this approach is strongly dependent on the internal junctions between the polymer and the electron acceptor or donor. However, many fundamental questions remain regarding the underlying energy transfer processes involved. Phase separation within domains should not in principle

• exceed the exciton diffusion length [12], which is the case for ECP–fullerene-based solar cells in which fullerene molecules are able to capture the negative charges while the holes remain on the conjugated polymer [13]. Still, evidence for similar photoinduced charge-transfer or energy-transfer

Optimization of phase contrast in bimodal amplitude modulation AFM

• Mehrnoosh Damircheli,
• Amir F. Payam and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2015, 6, 1072–1081, doi:10.3762/bjnano.6.108

• are not associated with changes in the sign of the average value of the force. The origin of those regimes are discussed in terms of the different energies of the system, kinetic energy of the exited modes [35][36][37][38], the input energy [36] or the energy transfer between the modes [37]. In

• has a higher Hamaker constant. The power dissipated by the 2nd mode also shows a maximum with A1/A01 near 0.2 (Figure 4c). A discussion about the energy transfer among different modes is presented by Solares and co-workers [48]. The data plotted in Figure 3 and Figure 4 has been obtained by using the

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• emitted green luminescent light due to Tb3+. In the excitation spectra, a peak centered at 254 nm was observed which was attributed to Ce3+→Tb3+ energy transfer transition. Zhang et al. [27] reported the synthesis of a hybrid nanocomposite material of magnetic and luminescent NPs inside silica spheres

Carrier multiplication in silicon nanocrystals: ab initio results

• Ivan Marri,
• Marco Govoni and
• Stefano Ossicini

Beilstein J. Nanotechnol. 2015, 6, 343–352, doi:10.3762/bjnano.6.33

• absorbs at least one photon. This process was explained by considering a new energy transfer-based CM scheme, space-separated quantum cutting (SSQC). CM by SSQC is driven by the Coulomb interaction between carriers of different NCs and differs from traditional CM dynamics because the generated e–h pairs

• , energy transfer process that occurs when a high energy electron (hole) decays toward the conduction (valence) band CB (VB) edge by promoting the formation of an extra e–h pair in a nearby NC. CDCT, instead, is a Coulomb-driven, charge transfer mechanism that occurs when an electron (hole) decays toward

Tunable white light emission by variation of composition and defects of electrospun Al₂O₃–SiO₂ nanofibers

• Jinyuan Zhou,
• Gengzhi Sun,
• Hao Zhao,
• Xiaojun Pan,
• Zhenxing Zhang,
• Yujun Fu,
• Yanzhe Mao and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 313–320, doi:10.3762/bjnano.6.29

• 2:1 mullites have a wide band gap of 7.7 ± 0.2 eV, which is too wide for our case. Therefore, based on the above analysis, we assign an energy transfer mechanism to describe our PL results, as shown in Figure 5d. First, most of the energy needed for the excitation of radical carbonyl defects (≡Si(Al

• . The inset optical photos in (a) and (c) are the corresponding light emission spot of Al6Si4 and Al4Si6 samples, respectively. (d) Energy transfer diagram indicating the mechanism for Al2O3–SiO2 nanocomposite emission. The dashed lines represent light absorption, the solid lines radiative transitions

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

• Rudolf Herrmann,
• Markus Rennhak and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

• ]. Fluorescence lifetime imaging microscopy (FLIM) on CeO2 agglomerates (50 ± 5 nm diameter of the circumscribed sphere) with and without platinum decoration did not show any difference between both samples. We can therefore conclude that there is no efficient energy transfer between metal and fluorescence dye

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• local dielectric function surrounding the Au nanoparticles; it is decreased significantly by the conjugation of an electron deficient material such as MnO or Fe3O4. A different approach utilizes an energy transfer between the gold domain and the metal oxide to explain the bathochromic shift [79][80]. On

Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes

• Marcela Elisabeta Barbinta-Patrascu,
• Stefan Marian Iordache,
• Ana Maria Iordache,
• Nicoleta Badea and
• Camelia Ungureanu

Beilstein J. Nanotechnol. 2014, 5, 2316–2325, doi:10.3762/bjnano.5.240

• efficient energy transfer between the Chla molecules incorporated in liposomes (ordered along SWCNTs) as a result of interaction with the carbon nanotube sidewall. These findings are in agreement with our previous studies [4][5]. As can be seen in both Figure 4 and Figure 5, the liquid crystal phase of

• biomimetic membranes (above 41 °C) exhibits low anisotropy and high fluorescence emission intensity due to an increase in the lipid bilayer mobility and hence the chlorophyll has the possibility to move and to minimize the energy transfer leading to fluorescence quenching. In the gel phase of the artificial

• their small size as compared to the samples without cholesterol (see Figure 2). This leads to fluorescence quenching due to the efficient energy transfer between chlorophyll molecules, which are closer in small vesicles. Morphological characterization of biohybrid architectures Figure 6 shows a partial

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• distinct propagating wave frequencies, promote to fulfil the phase matching condition Δk = 0 in a collinear geometry (see Figure 2b and Figure 2d). Therefore, specific beam propagation angles have to be set to achieve the phase matching and ensure an optimal energy transfer from the incident beams to the

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

• of [Fe(dpp)2](BF)4 and Chl a, the authors excluded the possibility of an energy transfer from the excited Chl a to the SCO complex in the LS state. These observations suggests that the excited form of Chl a does not exist in the OLEDs at low temperatures [29]. To explain these findings, the authors

• manner, the luminescence will be modulated as the complex switches its spin state. Nonetheless, in order to render this approach valuable at the nanoscale, it is imperative to place the luminophore close to the metallic centers of the complex (≈1–3 nm) to establish a non-radiative energy transfer [31

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

• 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

• -phase correlation between the individual electronic excitations of the whole oscillator ensemble (elastic process). The second explains the decay in terms of the energy transfer into quasi-particles (electron–hole pairs; inelastic processes). The dephasing results in the loss of coherence of the

Dissipation signals due to lateral tip oscillations in FM-AFM

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2014, 5, 2048–2057, doi:10.3762/bjnano.5.213

• . Results and Discussion Dissipation spectroscopy Energy transfer within one cycle As a first application of the model, we calculate the energy transfer from the normal into the lateral degree of freedom for different nominal distances. The motion starts at the upper turning point of the normal oscillation

• to p < 1 the number of these oscillations is limited by αmax = ωx/ωz. The dependence of the energy transfer in a single cycle on the frequency ratio ωx/ωz is shown for the numerical solution as the full curve in Figure 3. Like the simplified result in Equation 8 it starts at 0 for ωx/ωz = 0, then

• displacement becomes zero for infinite lateral stiffness. Energy transfer and dissipation after multiple cycles After we have discussed the energy transfer into the lateral degree of freedom within one cycle, we can now consider the actual dissipation rate after multiple cycles. We evaluate the dissipation

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

• measurement of membrane potentials over a millisecond time-scale in real time. Hall et al. [137] recently proposed the use of a single crystal ND substrate containing a layer of NV as a non-invasive model for a detection set-up based on Förster resonance energy transfer and optically detected magnetic

Controlling the optical and structural properties of ZnS–AgInS₂ nanocrystals by using a photo-induced process

• Takashi Yatsui,
• Fumihiro Morigaki and
• Tadashi Kawazoe

Beilstein J. Nanotechnol. 2014, 5, 1767–1773, doi:10.3762/bjnano.5.187

• ], quantum dots (QDs) [4], quantum wells [5], and quantum rings [6]. Kawazoe et al., have demonstrated the room-temperature operation of AND-gate and NOT-gate devices using InAs QD pairs [7]. In a nanophotonic device, near-field energy-transfer via a dipole-forbidden energy state, which is unattainable in

• conventional photonic devices, is used [8]. The near-field energy-transfer originates from an exchange of virtual photons between the resonant energy states [9], where the virtual photons on a nanoparticle activate the dipole-forbidden energy state. The successful fabrication of a nanophotonic device requires

A study on the consequence of swift heavy ion irradiation of Zn–silica nanocomposite thin films: electronic sputtering

• Compesh Pannu,
• Udai B. Singh,
• Dinesh. C. Agarwal,
• Saif A. Khan,
• Sunil Ojha,
• Ramesh Chandra,
• Hiro Amekura,
• Debdulal Kabiraj and
• Devesh. K. Avasthi

Beilstein J. Nanotechnol. 2014, 5, 1691–1698, doi:10.3762/bjnano.5.179

• occurs. It has potential applications in astrophysics, space devices and mass spectrometry of large molecules [10]. Sputtering occurs due to the energy transfer to the atoms in the target by incident ions through nuclear collision cascades (nuclear sputtering) produced in the target as well as electronic

Donor–acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions

• Anastasios Stergiou,
• Georgia Pagona and
• Nikos Tagmatarchis

Beilstein J. Nanotechnol. 2014, 5, 1580–1589, doi:10.3762/bjnano.5.170

• strong electronic interaction between TPP in the excited state and GO. Possible pathways for the fluorescence quenching of TPP are attributed either to an electron transfer or to an energy transfer to GO. Additionally, the formation of the charge-separated state (GO)•−–(TPP)•+ was shown to have an energy

• processes within the GO–Fc hybrid material. As described above, cations of transition metals are often present in chromophores (the central metal core of Pcs, porphyrins etc.) and take part in the electron/energy transfer processes. Very recently, a terpyridine (tpy) derivative, as a ligand for Fe(II) ions

• possess a short, yet rigid phenylene spacer between porphyrin and graphene. Photophysical measurements revealed the presence of a short-lived porphyrin singlet excited state (38 ps), however, without yielding the porphyrin radical cation, thus suggesting that energy transfer from the porphyrin excited

Synthesis of hydrophobic photoluminescent carbon nanodots by using L-tyrosine and citric acid through a thermal oxidation route

• Venkatesh Gude

Beilstein J. Nanotechnol. 2014, 5, 1513–1522, doi:10.3762/bjnano.5.164

• molecule detection, energy transfer [1]. A special form of carbon (smaller than 10 nm in size) exhibiting fascinating properties are carbon nanodots (CNDs), which are different in their properties from zero-band gap graphene, diamond, and fullerene. Carbon nanodots (CNDs) exhibit properties such as

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

• the reductive capacity of glutathione (the cytosolic concentration of which is between 5 and 10 mM) may be used to displace a fluorescence resonance energy transfer (FRET) acceptor on the surface of the NP as confirmation of a successful NP localization to the cytosol [55]. Such experiments are in

Near-field photochemical and radiation-induced chemical fabrication of nanopatterns of a self-assembled silane monolayer

• Ulrich C. Fischer,
• Carsten Hentschel,
• Florian Fontein,
• Linda Stegemann,
• Christiane Hoeppener,
• Harald Fuchs and
• Stefanie Hoeppener

Beilstein J. Nanotechnol. 2014, 5, 1441–1449, doi:10.3762/bjnano.5.156

• and protects the dye from photochemical bleaching by quenching the excited state of the dye molecules through energy transfer from the excited state to the metal [23]. In this near-field photochemical process it is the near field of the dipole-excited molecule, not the near field of the metal mask

• , which is important. This dipole-excitation is generated by far field illumination. The dipolar near field of the molecule leads to a quenching of the excited state of the molecule due to energy transfer to the metal nanostructure within the dipolar near field range of the molecule [25]. As a

• photochemical reaction is, in general, a chemical reaction starting from the excited state of the molecule, a quenching of the excited state competes with and inhibits the photochemical reaction. The short range of the dipolar near field of the excited molecule and thus of the energy transfer process leads to

An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals

• Parul Chawla,
• Son Singh and
• Shailesh Narain Sharma

Beilstein J. Nanotechnol. 2014, 5, 1235–1244, doi:10.3762/bjnano.5.137

• across the donor–acceptor interface another possible mechanism of charge transportation could be energy transfer, i.e., the Forster resonance energy transfer (FRET) from the donor to the acceptor after excitation, which results in the generation of an exciton in the acceptor. This mechanism, however, can

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• coefficient, increased band-gap energy, a reduced carrier-scattering rate, and higher reactive sites [7][8][9][10], which sums up to nanomaterials having superior properties in light harvesting and energy transfer efficiency. Thus, the usage of nanomaterials as new building blocks has opened a new way to

• -absorption and photocatalysis action spectrum measurement to determine the underlying plasmonic energy-transfer mechanism [80]. Due to the insulating SiO2 shell the gold core can only transfer the plasmonic energy to the Cu2O shell by resonant energy transfer and the electron–hole pairs generated by the

Energy dissipation in multifrequency atomic force microscopy

• Valentina Pukhova,
• Francesco Banfi and
• Gabriele Ferrini

Beilstein J. Nanotechnol. 2014, 5, 494–500, doi:10.3762/bjnano.5.57

• mode. The energy is released by eigenmodes characterized by different oscillations frequencies, thus opening the possibility to resonant energy transfer to samples or (nano)structures endowed with mechanical resonances at the eigenmode frequencies. Finally, Figure 3 shows the evolution of the

Unlocking higher harmonics in atomic force microscopy with gentle interactions

• Sergio Santos,
• Victor Barcons,
• Josep Font and
• Albert Verdaguer

Beilstein J. Nanotechnol. 2014, 5, 268–277, doi:10.3762/bjnano.5.29

• Equation 7 needs to be considerably large, even when n is not necessarily very large. From Equation 8 it follows that An can be set to any arbitrary value by increasing F0n, even if there is no tip–sample energy transfer, i.e., En = 0. The higher harmonics for the free cantilever are termed A0n. This case

• supplied by the external drive at a given harmonic n implies that both positive and negative energy transfer might also occur at that frequency. Furthermore, when external drives are employed, this transfer occurs for a given phase shift that is now measured relative to the angle of the driving force. This