Janus-micromotor-based on–off luminescence sensor for active TNT detection

• Ye Yuan,
• Changyong Gao,
• Daolin Wang,
• Chang Zhou,
• Baohua Zhu and
• Qiang He

Beilstein J. Nanotechnol. 2019, 10, 1324–1331, doi:10.3762/bjnano.10.131

• ], surface plasmon resonance [10], molecularly imprinted polymers [6], and fluorescence polarization [11] have been proposed to detect TNT. However, most of these techniques have major limitations such as cumbersome pretreatment, complicated operation, long detection time and high cost. In recent years

• surface charge of the UCNPs before and after modification was measured. As shown in Figure 1d, the zeta potential changed from −22.08 to 17.3 mV, indicating the successful surface amine group functionalization. Moreover, the fluorescence emission spectrum shows that the surface functionalization did not

• surface of the UCNPs could chemically recognize the TNT molecules efficiently and form a Meisenheimer complex which has a strong absorption within the emission spectrum of the UCNPs. Due to the fluorescence resonance energy transfer from the excited UCNPs to the complex, the luminescence intensity of the

Tailoring the magnetic properties of cobalt ferrite nanoparticles using the polyol process

• Malek Bibani,
• Romain Breitwieser,
• Alex Aubert,
• Vincent Loyau,
• Silvana Mercone,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2019, 10, 1166–1176, doi:10.3762/bjnano.10.116

• refluxing (3, 6 and 15 h). The structure, microstructure and composition of the resulting NPs were then investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray fluorescence spectroscopy (XRF), respectively. The magnetic properties were also evaluated using standard

• well with the cubic spinel structure (ICDD no. 98-003-9131). The crystal size of each sample has been estimated through computational Rietveld refinements using MAUD software [26] (Table 1). Then, the compositions have been checked by X-ray fluorescence (XRF) experiments (Figure 2). The crystal sizes

• NPs have been well characterized using X-ray techniques (diffraction and fluorescence) and transmission electron microscopy. Most of the NPs are above 10 nm in size, magnetically stable and blocked at room temperature (TB > RT). Moreover, they exhibit saturation magnetization values among the highest

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• fluorescence shift was derived from Figure 6. (c, d) Intracellular ROS levels were normalized to the H2O2 levels. *,# p < 0.05 compared to the corresponding results with H2O2 and γ-Fe2O3@Hep, respectively. Values are shown as the mean ± SE (n = 3–4). A schematic of the iron oxide nanoparticle coating with

Correlation of surface-enhanced Raman scattering (SERS) with the surface density of gold nanoparticles: evaluation of the critical number of SERS tags for a detectable signal

• Vincenzo Amendola

Beilstein J. Nanotechnol. 2019, 10, 1016–1023, doi:10.3762/bjnano.10.102

• the absence of blinking or bleaching, and the possibility to excite in the red or near infrared spectral range, where most matrixes and substrates have low fluorescence background [13][17]. Therefore, due to the increasing demand for ultrasensitive identification and quantification of specific

Serum type and concentration both affect the protein-corona composition of PLGA nanoparticles

• Katrin Partikel,
• Robin Korte,
• Dennis Mulac,
• Hans-Ulrich Humpf and
• Klaus Langer

Beilstein J. Nanotechnol. 2019, 10, 1002–1015, doi:10.3762/bjnano.10.101

• -containing medium [37]. Therefore, we assumed a stable entrapment of the model drug even in the presence of proteins. Consequently, the Lumogen® Red fluorescence measured in cell culture experiments could be directly associated with the interaction between NPs and cells and is not distorted by effects of dye

• , when compared to the bare NPs. PLGA NPs preincubated with 500 µL FBS lead to the highest total red object area of 18.22 mm2/well. The results are consistent with the fluorescence microscopy images which were taken after an incubation time of 6 h (Figure 8). Furthermore, the images clearly demonstrate

• ® Red was analyzed by HPLC using a fluorescence detector (Agilent Technologies 1200 Series, Agilent Technologies GmbH, Böblingen, Germany) [37]. Therefore, an aliquot of NP suspension corresponding to 1 mg of PLGA NPs was centrifuged for 30 min at 30,000g. Following this, the supernatant was discarded

Experimental study of an evanescent-field biosensor based on 1D photonic bandgap structures

• Jad Sabek,
• Francisco Javier Díaz-Fernández,
• Luis Torrijos-Morán,
• Zeneida Díaz-Betancor,
• Ángel Maquieira,
• María-José Bañuls,
• Elena Pinilla-Cienfuegos and
• Jaime García-Rupérez

Beilstein J. Nanotechnol. 2019, 10, 967–974, doi:10.3762/bjnano.10.97

• the immobilization density by fluorescence microarray measurements, densities corresponding to a close-packed monolayer of the half-antibodies were obtained with standard deviation of 8% indicating a good reproducibility of the immobilization method [13]. Biosensing experiment Figure 7 shows the

Structural and optical properties of penicillamine-protected gold nanocluster fractions separated by sequential size-selective fractionation

• Xiupei Yang,
• Zhengli Yang,
• Fenglin Tang,
• Jing Xu,
• Maoxue Zhang and
• Martin M. F. Choi

Beilstein J. Nanotechnol. 2019, 10, 955–966, doi:10.3762/bjnano.10.96

• and size-selective fraction samples in Figure 9B were obtained at 25 °C at an excitation wavelength of 380 nm. The maximum emission peak of the PL spectrum of the original sample is 867 nm, while the fluorescence emission from the first fraction to the last fraction obtained by SSSP shows a blue shift

Effects of gold and PCL- or PLLA-coated silica nanoparticles on brain endothelial cells and the blood–brain barrier

• Aniela Bittner,
• Angélique D. Ducray,
• Hans Rudolf Widmer,
• Michael H. Stoffel and
• Meike Mevissen

Beilstein J. Nanotechnol. 2019, 10, 941–954, doi:10.3762/bjnano.10.95

• of a silica-core doped with rhodamine to enable visualization via fluorescence microscopy, followed by a layer of PCL/ICG and a surface coating with either PCL or PLLA. Characterization of these particle types showed a size of 90 nm for PCL-NPs and 95 nm for PLLA-NPs. The zeta potential was −25.4 mV

• Solution (HBSS) (Sigma, Switzerland). Inserts were transferred to 24-well plates containing TB and filled with dextran solution. After 60 min the fluorescence of samples from the donor and receiver solution at different time points was detected at 492 nm (excitation), 518 nm (emission) and 550 nm, 580 nm

Synthesis of novel C-doped g-C₃N₄ nanosheets coupled with CdIn₂S₄ for enhanced photocatalytic hydrogen evolution

• Jingshuai Chen,
• Chang-Jie Mao,
• Helin Niu and
• Ji-Ming Song

Beilstein J. Nanotechnol. 2019, 10, 912–921, doi:10.3762/bjnano.10.92

• , NEXUS-870, Nicolet Instrument Co. USA), X-ray diffraction (XRD, XD-3, Purkinje General, China, Cu Kα radiation), X-ray photoelectron spectroscopy (XPS, Escalab 250Xi, America), UV–vis diffuse reflectance spectroscopy (DRS, Hitachi U-4100) at a wavelength range of 200–800 nm, and fluorescence

Polydopamine-coated Au nanorods for targeted fluorescent cell imaging and photothermal therapy

• Boris N. Khlebtsov,
• Andrey M. Burov,
• Timofey E. Pylaev and
• Nikolai G. Khlebtsov

Beilstein J. Nanotechnol. 2019, 10, 794–803, doi:10.3762/bjnano.10.79

• excitation of free rhodamine 123 (curve 1) and AuNRs-PDA-R123-folate (curve 2) solutions at roughly equivalent concentrations of dye. The fluorescence intensity of R123 was found to be quenched with a quenching factor of about 0.75. As the rhodamine 123 molecules are well separated by a 10 nm PDA shell from

• obtained composite nanoparticles that have two important theranostic modalities. First, due to the strong light absorption by the AuNR core, the nanoparticles are suitable for photothermal treatment in the NIR tissue transparency window. Second, the nanocomposite shows strong fluorescence under visible

• fluorescent microscope. As shown in Figure 2C, the fluorescence signal inside HeLa cells could be detected after the incubation of cells with folate-targeted nanocomposites, illustrating that AuNR-PDA-R123-folate could be effectively internalized into HeLa cells. The nonspecific uptake of PEG-coated

Towards rare-earth-free white light-emitting diode devices based on the combination of dicyanomethylene and pyranine as organic dyes supported on zinc single-layered hydroxide

• Jeff L. Nyalosaso,
• Rachod Boonsin,
• Pierre Vialat,
• Damien Boyer,
• Geneviève Chadeyron,
• Rachid Mahiou and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2019, 10, 760–770, doi:10.3762/bjnano.10.75

• with commercial blue or UV LEDs to generate coloured light and white light. However, most of them exhibit luminescence properties only in liquid solution when any aggregation-induced quenching is prevented. But we have shown recently that the dyes can exhibit fluorescence in the solid state when they

• the same time the organic dyes from aggregation [16]. Indeed, the aggregation of organic molecules leading to the quenching of their fluorescence occurs when the hybrid compound (SLH-Dye) is prepared in the dry solid state. The originality of our preparation process lies in the dispersion of the

• occur. Photoluminescence properties of the integrated dyes Absolute quantum yield (QYab) is defined as the efficiency at which a given material re-emits by fluorescence a certain number of photons absorbed at a given wavelength. The parameters measured in a 3.3 inch integrating sphere provide

Outstanding chain-extension effect and high UV resistance of polybutylene succinate containing amino-acid-modified layered double hydroxides

• Adam A. Marek,
• Vincent Verney,
• Christine Taviot-Gueho,
• Grazia Totaro,
• Laura Sisti,
• Annamaria Celli and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2019, 10, 684–695, doi:10.3762/bjnano.10.68

• PC spectrophotometer. Kubelka–Munk theory was applied to the LDH filler data to transform the diffuse reflectance spectra into absorption spectra. The fluorescence spectra of PBS–LDH nanocomposites were recorded with a Perkin-Elmer LS-55 luminescence spectrophotometer equipped with a front surface

• transmittance decreases during 40 h and then increases. This phenomenon may be caused by the transformation of amino acid molecules in the LDH structure or their interaction with the polymer matrix. Similar trends have been also registered using fluorescence spectroscopy (Figure 11). The intense emission band

• nanocomposites with Mg2Al LDH during photodegradation tests at 60 °C. UV–vis transmittance spectra of PBS and PBS nanocomposites with Mg2Al LDH fillers. Fluorescence spectra of PBS nanocomposites with Mg2Al LDH fillers, during photodegradation tests at 60 °C; (a) PBS–LDH/HIS and (b) PBS–LDH/PHE. The excitation

Ultrasonication-assisted synthesis of CsPbBr₃ and Cs₄PbBr₆ perovskite nanocrystals and their reversible transformation

• Longshi Rao,
• Xinrui Ding,
• Xuewei Du,
• Guanwei Liang,
• Yong Tang,
• Kairui Tang and
• Jin Z. Zhang

Beilstein J. Nanotechnol. 2019, 10, 666–676, doi:10.3762/bjnano.10.66

• -sonication at a power of 120 W for 40 min. During the sonication, the colorless reaction medium gradually transformed into a yellow and then an orange-yellow solution, which suggests the formation of PNCs and demonstrates strong fluorescence emission under 365 nm UV light excitation. After completion of the

• UV–vis spectrometer (Shimadzu, Japan) over the wavelength range from 300 to 700 nm, at 1 nm intervals. The PL spectra of the PNCs were recorded using a fluorescence spectrophotometer (RF-6000, Shimadzu, Japan) using a Xe lamp as an excitation source. Characterization of the CsPbBr3 PNCs prepared

Ceria/polymer nanocontainers for high-performance encapsulation of fluorophores

• Kartheek Katta,
• Dmitry Busko,
• Yuri Avlasevich,
• Katharina Landfester,
• Stanislav Baluschev and
• Rafael Muñoz-Espí

Beilstein J. Nanotechnol. 2019, 10, 522–530, doi:10.3762/bjnano.10.53

• an increase in the fluorescence of the model organic fluorophore terrylene diimide by avoiding the ground-state molecular oxygen to react with electronically excited states of the fluorescent hydrocarbon molecule. Keywords: cerium oxide; crystallization; miniemulsion; nanocapsule; photoluminescence

• unwanted chemical reactions [13]. Molecular oxygen is a well-known quencher of fluorescence. Consequently, the shell properties of the nanocontainers are often customized to protect the fluorophore encapsulated into a liquid core. Higher lying singlet states of a fluorophore are relatively short living and

• , singlet oxygen is obtained through the process of fluorescence quenching [13][14][15][16]. Photooxidation significantly changes the emission properties of fluorophores because of an irreversible chemical reaction. In a simple description, the longer the fluorescence lifetime and the lower the fluorescence

Integration of LaMnO_3+δ films on platinized silicon substrates for resistive switching applications by PI-MOCVD

• Raquel Rodriguez-Lamas,
• Dolors Pla,
• Odette Chaix-Pluchery,
• Benjamin Meunier,
• Fabrice Wilhelm,
• Andrei Rogalev,
• Laetitia Rapenne,
• Xavier Mescot,
• Quentin Rafhay,
• Hervé Roussel,
• Michel Boudard,
• Carmen Jiménez and
• Mónica Burriel

Beilstein J. Nanotechnol. 2019, 10, 389–398, doi:10.3762/bjnano.10.38

• beamline (Grenoble, France). Measurements were taken under vacuum at 25 °C in fluorescence mode using a nearly constant 200 mA beam current. Two silicon photodiodes detectors were used to collect the total fluorescence, one in back-scattering geometry and a second diode mounted at 90° with respect to the

Surface plasmon resonance enhancement of photoluminescence intensity and bioimaging application of gold nanorod@CdSe/ZnS quantum dots

• Siyi Hu,
• Yu Ren,
• Yue Wang,
• Jinhua Li,
• Junle Qu,
• Liwei Liu,
• Hanbin Ma and
• Yuguo Tang

Beilstein J. Nanotechnol. 2019, 10, 22–31, doi:10.3762/bjnano.10.3

• with them [6][7][8][9][10][11][12]. Research conducted to date shows that the fluorescence intensity of QDs changes when other chemical materials or ions are added. The CdSe/ZnS heterostructures of QDs are of interest due to their high quantum efficiency [13][14][15]. Furthermore, the heterostructure

• metal materials play a role in the enhancement of fluorescence in QDs, especially gold nanorods (GNRs) and Cu or Ca+ ion binding of QDs [16][17][18][19]. GNRs possess two plasmonic resonance bands – a longitudinal band and a transverse band. These bands correspond to the electron oscillations along the

• , and fluorescence enhancement. When QDs bind with GNRs, the fluorescence intensity of the QDs is enhanced by the near-fired plasmonic resonance from the GNR surface and their photoluminescence (PL) emission increases [20][21][22][23]. Richard A. Vaia and co-authors reported a five times higher

The nanoscaled metal-organic framework ICR-2 as a carrier of porphyrins for photodynamic therapy

• Jan Hynek,
• Sebastian Jurík,
• Martina Koncošová,
• Jaroslav Zelenka,
• Ivana Křížová,
• Tomáš Ruml,
• Kaplan Kirakci,
• Ivo Jakubec,
• František Kovanda,
• Kamil Lang and
• Jan Demel

Beilstein J. Nanotechnol. 2018, 9, 2960–2967, doi:10.3762/bjnano.9.275

• by powder XRD, TEM, DLS, and UV–vis and fluorescence spectroscopy. The powder XRD patterns of all composites, depicted in Figure 4 and Figure S5 (Supporting Information File 1), do not show significant changes in comparison with that of the parent nanoICR-2. Also, the coherent diffraction domain of

• in PBS it resulted in amorphisation of the ICR-2 nanoparticles, and in the case of nanoICR-2/porphyrin in partial dissolution of the porphyrin. In order to ascertain the effects of the MOF structure on the porphyrin units, UV–vis absorption and fluorescence spectra were measured and compared with the

• because of partial porphyrin aggregation. The magnitude of aggregation is in the order TPPPi(Ph) < TPPPi(iPr) ≈ TPPPi(Me). When excited at 415 nm, the dispersions of nanoICR-2/porphyrin in EtOH exhibit red fluorescence with two bands at 655 and 720 nm (Figure S9, Supporting Information File 1). The

Time-resolved universal temperature measurements using NaYF₄:Er³⁺,Yb³⁺ upconverting nanoparticles in an electrospray jet

• Kristina Shrestha,
• Arwa A. Alaulamie,
• Ali Rafiei Miandashti and
• Hugh H. Richardson

Beilstein J. Nanotechnol. 2018, 9, 2916–2924, doi:10.3762/bjnano.9.270

• UCNPs minimizes tissue damage [2], is relatively free of background fluorescence [3], and has a high penetration depth [3][4]. Time-resolved temperature measurements using the luminescence intensity ratio (LIR) of UCNPs are rare [5][6]. Here we show that NaYF4:Er3+,Yb3+ UCNPs can provide time-resolved

Near-infrared light harvesting of upconverting NaYF₄:Yb³⁺/Er³⁺-based amorphous silicon solar cells investigated by an optical filter

• Daiming Liu,
• Qingkang Wang and
• Qing Wang

Beilstein J. Nanotechnol. 2018, 9, 2788–2793, doi:10.3762/bjnano.9.260

• ULTRA 55 scanning electron microscope at high voltage of 20 kV. Photoluminescence spectra from 500 to 700 nm were recorded with a steady-state & time-resolved fluorescence spectrofluorometer (QM/TM/IM, Photon Technology International) in conjunction with a 980 nm diode laser. The power during

Magnetic and luminescent coordination networks based on imidazolium salts and lanthanides for sensitive ratiometric thermometry

• Pierre Farger,
• Cédric Leuvrey,
• Mathieu Gallart,
• Pierre Gilliot,
• Guillaume Rogez,
• João Rocha,
• Duarte Ananias,
• Pierre Rabu and
• Emilie Delahaye

Beilstein J. Nanotechnol. 2018, 9, 2775–2787, doi:10.3762/bjnano.9.259

• attributed to the S1→S0 (peaking at ca. 415 nm) fluorescence and T1→S0 (peaking at 503 nm) ligand phosphorescence. This assignment is supported by the time-resolved emission spectra recorded at 12 K excited at 350 nm (Figure S6, Supporting Information File 1), which demonstrates a much faster time dependence

Comparative biological effects of spherical noble metal nanoparticles (Rh, Pd, Ag, Pt, Au) with 4–8 nm diameter

• Alexander Rostek,
• Marina Breisch,
• Kevin Pappert,
• Kateryna Loza,
• Marc Heggen,
• Manfred Köller,
• Christina Sengstock and
• Matthias Epple

Beilstein J. Nanotechnol. 2018, 9, 2763–2774, doi:10.3762/bjnano.9.258

• morphology of the incubated cells were analysed with calcein acetoxymethyl ester (calcein-AM, Calbiochem, Schwalbach, Germany) fluorescence staining. For this, the cells were incubated with 1 μM calcein-AM for 30 min at 37 °C under cell culture conditions and subsequently analysed by fluorescence microscopy

• (Olympus MVX10, Olympus, Hamburg, Germany). The quantification of cell viability was performed by phase analysis (CellSens Dimensions, Olympus, Hamburg, Germany) of calcein-positive fluorescence signals calculating the fluorescent area. For calculating the phase analysis data, a threshold was set which

• incubated with different nanoparticles (50 µg mL−1 = 50 ppm) under cell culture conditions and subsequently stained with calcein-AM. Viable cells are indicated by green fluorescence (A: control: untreated hMSC). Influence of noble metal nanoparticles on the viability of human mesenchymal stem cells. The

Oriented zinc oxide nanorods: A novel saturable absorber for lasers in the near-infrared

• Pavel Loiko,
• Tanujjal Bora,
• Josep Maria Serres,
• Haohai Yu,
• Magdalena Aguiló,
• Francesc Díaz,
• Uwe Griebner,
• Valentin Petrov,
• Xavier Mateos and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2018, 9, 2730–2740, doi:10.3762/bjnano.9.255

• , where M = Co, Mn, Ni or Cu). The energy levels of the intrinsic defects are located between the valence and conduction bands and have different ionization energies ranging from ≈0.05 to 2.8 eV [10]. Various emissions (fluorescence) in the visible (green, yellow and red) originating from the defects in

Low cost tips for tip-enhanced Raman spectroscopy fabricated by two-step electrochemical etching of 125 µm diameter gold wires

• Antonino Foti,
• Francesco Barreca,
• Enza Fazio,
• Cristiano D’Andrea,
• Paolo Matteini,
• Onofrio Maria Maragò and
• Pietro Giuseppe Gucciardi

Beilstein J. Nanotechnol. 2018, 9, 2718–2729, doi:10.3762/bjnano.9.254

• the () planes. (b) x–y fluorescence map of a gold tip (2.5 × 2.5 µm2, step size 125 nm). The dotted lines highlight the shape of the tip. (c) x–z fluorescence map of the gold tip (1.9 × 2.4 µm2, step size 100 nm). The pictograms illustrate the different focusing conditions. Each pixel represents the

Size-selected Fe₃O₄–Au hybrid nanoparticles for improved magnetism-based theranostics

• Maria V. Efremova,
• Yulia A. Nalench,
• Eirini Myrovali,
• Anastasiia S. Garanina,
• Ivan S. Grebennikov,
• Polina K. Gifer,
• Maxim A. Abakumov,
• Marina Spasova,
• Makis Angelakeris,
• Alexander G. Savchenko,
• Michael Farle,
• Natalia L. Klyachko,
• Alexander G. Majouga and
• Ulf Wiedwald

Beilstein J. Nanotechnol. 2018, 9, 2684–2699, doi:10.3762/bjnano.9.251

• full culture medium and in medium with NPs at 37 °C without AMF, were used as controls. The obtained preparations were analyzed using a fluorescence microscope (EVOS, life technologies), with a PlanFluor objective 10×/0.3. The further processing of the photos was carried out by ImageJ software. ROS

• and 10 mM HEPES (pH 7.4 adjusted with 1 N NaOH), and stained with 2 µM H2DCFDA solution (life technologies) for 30 min at 37 °C in darkness. Then the cells were carefully washed with HBSS three times for 5 min. The obtained preparations were analyzed using the EVOS fluorescence microscope with a

Cytotoxicity of doxorubicin-conjugated poly[N-(2-hydroxypropyl)methacrylamide]-modified γ-Fe₂O₃ nanoparticles towards human tumor cells

• Zdeněk Plichta,
• Yulia Kozak,
• Rostyslav Panchuk,
• Viktoria Sokolova,
• Matthias Epple,
• Lesya Kobylinska,
• Pavla Jendelová and
• Daniel Horák

Beilstein J. Nanotechnol. 2018, 9, 2533–2545, doi:10.3762/bjnano.9.236

• undifferentiated cells, mesenchymal stem cells were utilized. Cellular uptake of agents was studied by fluorescence microscopy and induction of cell death was visualized by live/dead assay. Dox-conjugated γ-Fe2O3@P(HPMA-MMAA) particles showed enhanced cytotoxicity in drug-sensitive and drug-resistant tumor cells

• attached to the cells. The cellular uptake was measured by fluorescence microscopy with a Keyence Biorevo BZ-9000 instrument (Osaka, Japan) equipped with filters for Texas Red (EX 560/40, DM 585, BA 630/75) at 20× magnification. Dox and its complexes were visible as red fluorescing dots. Live/dead assay

• -9000 fluorescence microscope. The live/dead kit determined the cell viability based on the cell membrane integrity. Living cells were stained by calcein AM, which emits green fluorescence (517 nm) after excitation by blue light (494 nm), whereas dead cells were stained by EthD-1, which emits red