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Nanomaterials, Volume 6, Issue 5 (May 2016)

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Research

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Open AccessArticle Application of L-Aspartic Acid-Capped ZnS:Mn Colloidal Nanocrystals as a Photosensor for the Detection of Copper (II) Ions in Aqueous Solution
Nanomaterials 2016, 6(5), 82; doi:10.3390/nano6050082
Received: 9 March 2016 / Revised: 14 April 2016 / Accepted: 25 April 2016 / Published: 27 April 2016
Cited by 1 | PDF Full-text (3888 KB) | HTML Full-text | XML Full-text
Abstract
Water-dispersible ZnS:Mn nanocrystals (NCs) were synthesized by capping the surface with polar L-aspartic acid (Asp) molecules. The obtained ZnS:Mn-Asp NC product was optically and physically characterized using the corresponding spectroscopic methods. The ultra violet-visible (UV-VIS) absorption spectrum and photoluminescence (PL) emission spectrum of
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Water-dispersible ZnS:Mn nanocrystals (NCs) were synthesized by capping the surface with polar L-aspartic acid (Asp) molecules. The obtained ZnS:Mn-Asp NC product was optically and physically characterized using the corresponding spectroscopic methods. The ultra violet-visible (UV-VIS) absorption spectrum and photoluminescence (PL) emission spectrum of the NCs showed broad peaks at 320 and 590 nm, respectively. The average particle size measured from the obtained high resolution-transmission electron microscopy (HR-TEM) image was 5.25 nm, which was also in accordance with the Debye-Scherrer calculations using the X-ray diffraction (XRD) data. Moreover, the surface charge and degree of aggregation of the ZnS:Mn-Asp NCs were determined by electrophoretic and hydrodynamic light scattering methods, respectively. These results indicated the formation of agglomerates in water with an average size of 19.8 nm, and a negative surface charge (−4.58 mV) in water at ambient temperature. The negatively-charged NCs were applied as a photosensor for the detection of specific cations in aqueous solution. Accordingly, the ZnS:Mn-Asp NCs showed an exclusive luminescence quenching upon addition of copper (II) cations. The kinetic mechanism study on the luminescence quenching of the NCs by the addition of the Cu2+ ions proposed an energy transfer through the ionic binding between the two oppositely-charged ZnS:Mn-Asp NCs and Cu2+ ions. Full article
(This article belongs to the Special Issue Current Trends in Colloidal Nanocrystals)
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Open AccessArticle Noise Removal with Maintained Spatial Resolution in Raman Images of Cells Exposed to Submicron Polystyrene Particles
Nanomaterials 2016, 6(5), 83; doi:10.3390/nano6050083
Received: 5 February 2016 / Revised: 21 April 2016 / Accepted: 26 April 2016 / Published: 29 April 2016
Cited by 3 | PDF Full-text (5217 KB) | HTML Full-text | XML Full-text
Abstract
The biodistribution of 300 nm polystyrene particles in A549 lung epithelial cells has been studied with confocal Raman spectroscopy. This is a label-free method in which particles and cells can be imaged without using dyes or fluorescent labels. The main drawback with Raman
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The biodistribution of 300 nm polystyrene particles in A549 lung epithelial cells has been studied with confocal Raman spectroscopy. This is a label-free method in which particles and cells can be imaged without using dyes or fluorescent labels. The main drawback with Raman imaging is the comparatively low spatial resolution, which is aggravated in heterogeneous systems such as biological samples, which in addition often require long measurement times because of their weak Raman signal. Long measurement times may however induce laser-induced damage. In this study we use a super-resolution algorithm with Tikhonov regularization, intended to improve the image quality without demanding an increased number of collected pixels. Images of cells exposed to polystyrene particles have been acquired with two different step lengths, i.e., the distance between pixels, and compared to each other and to corresponding images treated with the super-resolution algorithm. It is shown that the resolution after application of super-resolution algorithms is not significantly improved compared to the theoretical limit for optical microscopy. However, to reduce noise and artefacts in the hyperspectral Raman images while maintaining the spatial resolution, we show that it is advantageous to use short mapping step lengths and super-resolution algorithms with appropriate regularization. The proposed methodology should be generally applicable for Raman imaging of biological samples and other photo-sensitive samples. Full article
(This article belongs to the Special Issue Nanoparticles in Bioimaging)
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Open AccessArticle Rapid Nanoparticle Synthesis by Magnetic and Microwave Heating
Nanomaterials 2016, 6(5), 85; doi:10.3390/nano6050085
Received: 17 February 2016 / Revised: 5 April 2016 / Accepted: 29 April 2016 / Published: 5 May 2016
Cited by 3 | PDF Full-text (2190 KB) | HTML Full-text | XML Full-text
Abstract
Traditional hot-injection (HI) syntheses of colloidal nanoparticles (NPs) allows good separation of the nucleation and growth stages of the reaction, a key limitation in obtaining monodisperse NPs, but with limited scalability. Here, two methods are presented for obtaining NPs via rapid heating: magnetic
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Traditional hot-injection (HI) syntheses of colloidal nanoparticles (NPs) allows good separation of the nucleation and growth stages of the reaction, a key limitation in obtaining monodisperse NPs, but with limited scalability. Here, two methods are presented for obtaining NPs via rapid heating: magnetic and microwave-assisted. Both of these techniques provide improved engineering control over the separation of nucleation and growth stages of nanomaterial synthesis when the reaction is initiated from room temperature. The advantages of these techniques with preliminary data are presented in this prospective article. It is shown here that microwave assisted heating could possibly provide some selectivity in activating the nanomaterial precursor materials, while magnetic heating can produce very tiny particles in a very short time (even on the millisecond timescale), which is important for scalability. The fast magnetic heating also allows for synthesizing larger particles with improved size distribution, therefore impacting, not only the quantity, but the quality of the nanomaterials. Full article
(This article belongs to the Special Issue Current Trends in Colloidal Nanocrystals)
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Open AccessArticle Graphene FETs with Low-Resistance Hybrid Contacts for Improved High Frequency Performance
Nanomaterials 2016, 6(5), 86; doi:10.3390/nano6050086
Received: 16 February 2016 / Revised: 14 April 2016 / Accepted: 3 May 2016 / Published: 10 May 2016
Cited by 1 | PDF Full-text (4376 KB) | HTML Full-text | XML Full-text
Abstract
This work proposes a novel geometry field effect transistor with graphene as a channel—graphene field-effect transistor (GFET), having a hybrid contact that consists of an ohmic source/drain and its extended part towards the gate, which is capacitively coupled to the channel. The ohmic
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This work proposes a novel geometry field effect transistor with graphene as a channel—graphene field-effect transistor (GFET), having a hybrid contact that consists of an ohmic source/drain and its extended part towards the gate, which is capacitively coupled to the channel. The ohmic contacts are used for direct current (DC) biasing, whereas their capacitive extension reduces access region length and provides the radio frequency (RF) signal a low impedance path. Minimization of the access region length, along with the paralleling of ohmic contact’s resistance and resistive part of capacitively coupled contact’s impedance, lower the overall source/drain resistance, which results in an increase in current gain cut-off frequency, fT. The DC and high-frequency characteristics of the two chosen conventional baseline GFETs, and their modified versions with proposed hybrid contacts, have been extensively studied, compared, and analyzed using numerical and analytical techniques. Full article
(This article belongs to the Special Issue 2D Nanomaterials: Graphene and Beyond Graphene)
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Open AccessArticle Rapamycin Loaded Solid Lipid Nanoparticles as a New Tool to Deliver mTOR Inhibitors: Formulation and in Vitro Characterization
Nanomaterials 2016, 6(5), 87; doi:10.3390/nano6050087
Received: 29 January 2016 / Revised: 27 April 2016 / Accepted: 29 April 2016 / Published: 9 May 2016
Cited by 1 | PDF Full-text (4050 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Recently, the use of mammalian target of rapamycin (mTOR) inhibitors, in particular rapamycin (Rp), has been suggested to improve the treatment of neurodegenerative diseases. However, as Rp is a strong immunosuppressant, specific delivery to the brain has been postulated to avoid systemic exposure.
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Recently, the use of mammalian target of rapamycin (mTOR) inhibitors, in particular rapamycin (Rp), has been suggested to improve the treatment of neurodegenerative diseases. However, as Rp is a strong immunosuppressant, specific delivery to the brain has been postulated to avoid systemic exposure. In this work, we fabricated new Rp loaded solid lipid nanoparticles (Rp-SLN) stabilized with polysorbate 80 (PS80), comparing two different methods and lipids. The formulations were characterized by differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), wide angle X-ray scattering (WAXS), cryo-transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS) and particle tracking. In vitro release and short-term stability were assessed. Biological behavior of Rp-SLN was tested in SH-SY5Y neuroblastoma cells. The inhibition of mTOR complex 1 (mTORC1) was evaluated over time by a pulse-chase study compared to free Rp and Rp nanocrystals. Compritol Rp-SLN resulted more stable and possessing proper size and surface properties with respect to cetyl palmitate Rp-SLN. Rapamycin was entrapped in an amorphous form in the solid lipid matrix that showed partial crystallinity with stable Lβ, sub-Lα and Lβ′ arrangements. PS80 was stably anchored on particle surface. No drug release was observed over 24 h and Rp-SLN had a higher cell uptake and a more sustained effect over a week. The mTORC1 inhibition was higher with Rp-SLN. Overall, compritol Rp-SLN show suitable characteristics and stability to be considered for further investigation as Rp brain delivery system. Full article
(This article belongs to the Special Issue Nanomaterials for Tissue Engineering)
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Open AccessArticle Investigation of the Structural, Electrical, and Optical Properties of the Nano-Scale GZO Thin Films on Glass and Flexible Polyimide Substrates
Nanomaterials 2016, 6(5), 88; doi:10.3390/nano6050088
Received: 7 March 2016 / Revised: 21 April 2016 / Accepted: 29 April 2016 / Published: 10 May 2016
Cited by 2 | PDF Full-text (4198 KB) | HTML Full-text | XML Full-text
Abstract
In this study, Ga2O3-doped ZnO (GZO) thin films were deposited on glass and flexible polyimide (PI) substrates at room temperature (300 K), 373 K, and 473 K by the radio frequency (RF) magnetron sputtering method. After finding the deposition
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In this study, Ga2O3-doped ZnO (GZO) thin films were deposited on glass and flexible polyimide (PI) substrates at room temperature (300 K), 373 K, and 473 K by the radio frequency (RF) magnetron sputtering method. After finding the deposition rate, all the GZO thin films with a nano-scale thickness of about 150 ± 10 nm were controlled by the deposition time. X-ray diffraction patterns indicated that the GZO thin films were not amorphous and all exhibited the (002) peak, and field emission scanning electron microscopy showed that only nano-scale particles were observed. The dependences of the structural, electrical, and optical properties of the GZO thin films on different deposition temperatures and substrates were investigated. X-ray photoemission spectroscopy (XPS) was used to measure the elemental composition at the chemical and electronic states of the GZO thin films deposited on different substrates, which could be used to clarify the mechanism of difference in electrical properties of the GZO thin films. In this study, the XPS binding energy spectra of Ga2p3/2 and Ga2p1/2 peaks, Zn2p3/2 and Zn2p1/2 peaks, the Ga3d peak, and O1s peaks for GZO thin films on glass and PI substrates were well compared. Full article
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Open AccessArticle Modification of the Interfacial Interaction between Carbon Fiber and Epoxy with Carbon Hybrid Materials
Nanomaterials 2016, 6(5), 89; doi:10.3390/nano6050089
Received: 4 March 2016 / Revised: 3 May 2016 / Accepted: 3 May 2016 / Published: 12 May 2016
Cited by 5 | PDF Full-text (3760 KB) | HTML Full-text | XML Full-text
Abstract
The mechanical properties of the hybrid materials and epoxy and carbon fiber (CF) composites were improved significantly as compared to the CF composites made from unmodified epoxy. The reasons could be attributed to the strong interfacial interaction between the CF and the epoxy
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The mechanical properties of the hybrid materials and epoxy and carbon fiber (CF) composites were improved significantly as compared to the CF composites made from unmodified epoxy. The reasons could be attributed to the strong interfacial interaction between the CF and the epoxy composites for the existence of carbon nanomaterials. The microstructure and dispersion of carbon nanomaterials were characterized by transmission electron microscopy (TEM) and optical microscopy (OM). The results showed that the dispersion of the hybrid materials in the polymer was superior to other carbon nanomaterials. The high viscosity and shear stress characterized by a rheometer and the high interfacial friction and damping behavior characterized by dynamic mechanical analysis (DMA) indicated that the strong interfacial interaction was greatly improved between fibers and epoxy composites. Remarkably, the tensile tests presented that the CF composites with hybrid materials and epoxy composites have a better reinforcing and toughening effect on CF, which further verified the strong interfacial interaction between epoxy and CF for special structural hybrid materials. Full article
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Open AccessArticle Aggregation and Colloidal Stability of Commercially Available Al2O3 Nanoparticles in Aqueous Environments
Nanomaterials 2016, 6(5), 90; doi:10.3390/nano6050090
Received: 2 February 2016 / Revised: 28 April 2016 / Accepted: 3 May 2016 / Published: 13 May 2016
Cited by 4 | PDF Full-text (3459 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The aggregation and colloidal stability of three, commercially-available, gamma-aluminum oxide nanoparticles (γ-Al2O3 NPs) (nominally 5, 10, and 20–30 nm) were systematically examined as a function of pH, ionic strength, humic acid (HA) or clay minerals (e.g., montmorillonite) concentration using dynamic
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The aggregation and colloidal stability of three, commercially-available, gamma-aluminum oxide nanoparticles (γ-Al2O3 NPs) (nominally 5, 10, and 20–30 nm) were systematically examined as a function of pH, ionic strength, humic acid (HA) or clay minerals (e.g., montmorillonite) concentration using dynamic light scattering and transmission electron microscopy techniques. NPs possess pH-dependent surface charges, with a point of zero charge (PZC) of pH 7.5 to 8. When pH < PZC, γ-Al2O3 NPs are colloidally stable up to 100 mM NaCl and 30 mM CaCl2. However, significant aggregation of NPs is pronounced in both electrolytes at high ionic strength. In mixed systems, both HA and montmorillonite enhance NP colloidal stability through electrostatic interactions and steric hindrance when pH ≤ PZC, whereas their surface interactions are quite limited when pH > PZC. Even when pH approximates PZC, NPs became stable at a HA concentration of 1 mg·L−1. The magnitude of interactions and dominant sites of interaction (basal planes versus edge sites) are significantly dependent on pH because both NPs and montmorillonite have pH-dependent (conditional) surface charges. Thus, solution pH, ionic strength, and the presence of natural colloids greatly modify the surface conditions of commercial γ-Al2O3 NPs, affecting aggregation and colloidal stability significantly in the aqueous environment. Full article
(This article belongs to the Special Issue Engineered Nanomaterials in the Environment)
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Open AccessArticle Post-Plasma SiOx Coatings of Metal and Metal Oxide Nanoparticles for Enhanced Thermal Stability and Tunable Photoactivity Applications
Nanomaterials 2016, 6(5), 91; doi:10.3390/nano6050091
Received: 9 March 2016 / Revised: 29 April 2016 / Accepted: 9 May 2016 / Published: 13 May 2016
Cited by 3 | PDF Full-text (5490 KB) | HTML Full-text | XML Full-text
Abstract
The plasma-based aerosol process developed for the direct coating of particles in gases with silicon oxide in a continuous chemical vapor deposition (CVD) process is presented. It is shown that non-thermal plasma filaments induced in a dielectric barrier discharge (DBD) at atmospheric pressure
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The plasma-based aerosol process developed for the direct coating of particles in gases with silicon oxide in a continuous chemical vapor deposition (CVD) process is presented. It is shown that non-thermal plasma filaments induced in a dielectric barrier discharge (DBD) at atmospheric pressure trigger post-DBD gas phase reactions. DBD operating conditions are first scanned to produce ozone and dinitrogen pentoxide. In the selected conditions, these plasma species react with gaseous tetraethyl orthosilicate (TEOS) precursor downstream of the DBD. The gaseous intermediates then condense on the surface of nanoparticles and self-reactions lead to homogeneous solid SiOx coatings, with thickness from nanometer to micrometer. This confirms the interest of post-DBD injection of the organo-silicon precursor to achieve stable production of actives species with subsequent controlled thickness of SiOx coatings. SiOx coatings of spherical and agglomerated metal and metal oxide nanoparticles (Pt, CuO, TiO2) are achieved. In the selected DBD operating conditions, the thickness of homogeneous nanometer sized coatings of spherical nanoparticles depends on the reaction duration and on the precursor concentration. For agglomerates, operating conditions can be tuned to cover preferentially the interparticle contact zones between primary particles, shifting the sintering of platinum agglomerates to much higher temperatures than the usual sintering temperature. Potential applications for enhanced thermal stability and tunable photoactivity of coated agglomerates are presented. Full article
(This article belongs to the Special Issue Plasma Nanoengineering and Nanofabrication)
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Open AccessArticle PDE5 Inhibitors-Loaded Nanovesicles: Physico-Chemical Properties and In Vitro Antiproliferative Activity
Nanomaterials 2016, 6(5), 92; doi:10.3390/nano6050092
Received: 9 April 2016 / Revised: 8 May 2016 / Accepted: 11 May 2016 / Published: 18 May 2016
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Abstract
Novel therapeutic approaches are required for the less differentiated thyroid cancers which are non-responsive to the current treatment. In this study we tested an innovative formulation of nanoliposomes containing sildenafil citrate or tadalafil, phosphodiesterase-5 inhibitors, on two human thyroid cancer cell lines (TPC-1
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Novel therapeutic approaches are required for the less differentiated thyroid cancers which are non-responsive to the current treatment. In this study we tested an innovative formulation of nanoliposomes containing sildenafil citrate or tadalafil, phosphodiesterase-5 inhibitors, on two human thyroid cancer cell lines (TPC-1 and BCPAP). Nanoliposomes were prepared by the thin layer evaporation and extrusion methods, solubilizing the hydrophilic compound sildenafil citrate in the aqueous phase during the hydration step and dissolving the lipophilic tadalafil in the organic phase. Nanoliposomes, made up of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine monohydrate (DPPC), cholesterol, and N-(carbonyl-methoxypolyethylene glycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE-mPEG2000) (6:3:1 molar ratio), were characterized by a mean diameter of ~100 nm, a very low polydispersity index (~0.1) and a negative surface charge. The drugs did not influence the physico-chemical properties of the systems and were efficiently retained in the colloidal structure. By using cell count and MTT assay, we found a significant reduction of the viability in both cell lines following 24 h treatment with both nanoliposomal-encapsulated drugs, notably greater than the effect of the free drugs. Our findings demonstrate that nanoliposomes increase the antiproliferative activity of phosphodiesterase-5 inhibitors, providing a useful novel formulation for the treatment of thyroid carcinoma. Full article
(This article belongs to the Special Issue Nanomaterials for Cancer Therapies)
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Open AccessArticle Mechanochemical Synthesis of TiO2 Nanocomposites as Photocatalysts for Benzyl Alcohol Photo-Oxidation
Nanomaterials 2016, 6(5), 93; doi:10.3390/nano6050093
Received: 3 March 2016 / Revised: 4 May 2016 / Accepted: 7 May 2016 / Published: 18 May 2016
Cited by 5 | PDF Full-text (3075 KB) | HTML Full-text | XML Full-text
Abstract
TiO2 (anatase phase) has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO2-magnetically-separable nanocomposites (MAGSNC) photocatalysts with different TiO2 loading were synthesized using a simple
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TiO2 (anatase phase) has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO2-magnetically-separable nanocomposites (MAGSNC) photocatalysts with different TiO2 loading were synthesized using a simple one-pot mechanochemical method. Photocatalysts were characterized by a number of techniques and their photocatalytic activity was tested in the selective oxidation of benzyl alcohol to benzaldehyde. Extension of light absorption into the visible region was achieved upon titania incorporation. Results indicated that the photocatalytic activity increased with TiO2 loading on the catalysts, with moderate conversion (20%) at high benzaldehyde selectivity (84%) achieved for 5% TiO2-MAGSNC. These findings pointed out a potential strategy for the valorization of lignocellulosic-based biomass under visible light irradiation using designer photocatalytic nanomaterials. Full article
(This article belongs to the Special Issue Nanoparticles for Catalysis)
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Open AccessArticle Effects of Atomization Injection on Nanoparticle Processing in Suspension Plasma Spray
Nanomaterials 2016, 6(5), 94; doi:10.3390/nano6050094
Received: 4 February 2016 / Revised: 30 March 2016 / Accepted: 11 May 2016 / Published: 20 May 2016
Cited by 1 | PDF Full-text (4291 KB) | HTML Full-text | XML Full-text
Abstract
Liquid atomization is applied in nanostructure dense coating technology to inject suspended nano-size powder materials into a suspension plasma spray (SPS) torch. This paper presents the effects of the atomization parameters on the nanoparticle processing. A numerical model was developed to simulate the
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Liquid atomization is applied in nanostructure dense coating technology to inject suspended nano-size powder materials into a suspension plasma spray (SPS) torch. This paper presents the effects of the atomization parameters on the nanoparticle processing. A numerical model was developed to simulate the dynamic behaviors of the suspension droplets, the solid nanoparticles or agglomerates, as well as the interactions between them and the plasma gas. The plasma gas was calculated as compressible, multi-component, turbulent jet flow in Eulerian scheme. The droplets and the solid particles were calculated as discrete Lagrangian entities, being tracked through the spray process. The motion and thermal histories of the particles were given in this paper and their release and melting status were observed. The key parameters of atomization, including droplet size, injection angle and velocity were also analyzed. The study revealed that the nanoparticle processing in SPS preferred small droplets with better atomization and less aggregation from suspension preparation. The injection angle and velocity influenced the nanoparticle release percentage. Small angle and low initial velocity might have more nanoparticles released. Besides, the melting percentage of nanoparticles and agglomerates were studied, and the critical droplet diameter to ensure solid melting was drawn. Results showed that most released nanoparticles were well melted, but the agglomerates might be totally melted, partially melted, or even not melted at all, mainly depending on the agglomerate size. For better coating quality, the suspension droplet size should be limited to a critical droplet diameter, which was inversely proportional to the cubic root of weight content, for given critical agglomerate diameter of being totally melted. Full article
(This article belongs to the Special Issue Plasma Nanoengineering and Nanofabrication)
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Review

Jump to: Research

Open AccessReview Dye-Doped Fluorescent Silica Nanoparticles for Live Cell and In Vivo Bioimaging
Nanomaterials 2016, 6(5), 81; doi:10.3390/nano6050081
Received: 14 February 2016 / Revised: 20 April 2016 / Accepted: 20 April 2016 / Published: 27 April 2016
Cited by 6 | PDF Full-text (3701 KB) | HTML Full-text | XML Full-text
Abstract
The need for novel design strategies for fluorescent nanomaterials to improve our understanding of biological activities at the molecular level is increasing rapidly. Dye-doped fluorescent silica nanoparticles (SiNPs) emerge with great potential for developing fluorescence imaging techniques as a novel and ideal platform
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The need for novel design strategies for fluorescent nanomaterials to improve our understanding of biological activities at the molecular level is increasing rapidly. Dye-doped fluorescent silica nanoparticles (SiNPs) emerge with great potential for developing fluorescence imaging techniques as a novel and ideal platform for the monitoring of living cells and the whole body. Organic dye-containing fluorescent SiNPs exhibit many advantages: they have excellent biocompatibility, are non-toxic, highly hydrophilic, optically transparent, size-tunable and easily modified with various biomolecules. The outer silica shell matrix protects fluorophores from outside chemical reaction factors and provides a hydrophilic shell for the insoluble nanoparticles, which enhances the photo-stability and biocompatibility of the organic fluorescent dyes. Here, we give a summary of the synthesis, characteristics and applications of fluorescent SiNPs for non-invasive fluorescence bioimaging in live cells and in vivo. Additionally, the challenges and perspectives of SiNPs are also discussed. We prospect that the further development of these nanoparticles will lead to an exciting breakthrough in the understanding of biological processes. Full article
(This article belongs to the Special Issue Nanoparticles in Bioimaging)
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Open AccessReview Biosynthesis of Metal Nanoparticles: Novel Efficient Heterogeneous Nanocatalysts
Nanomaterials 2016, 6(5), 84; doi:10.3390/nano6050084
Received: 17 February 2016 / Revised: 19 April 2016 / Accepted: 26 April 2016 / Published: 5 May 2016
Cited by 3 | PDF Full-text (5810 KB) | HTML Full-text | XML Full-text
Abstract
This review compiles the most recent advances described in literature on the preparation of noble metal nanoparticles induced by biological entities. The use of different free or substituted carbohydrates, peptides, proteins, microorganisms or plants have been successfully applied as a new green concept
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This review compiles the most recent advances described in literature on the preparation of noble metal nanoparticles induced by biological entities. The use of different free or substituted carbohydrates, peptides, proteins, microorganisms or plants have been successfully applied as a new green concept in the development of innovative strategies to prepare these nanoparticles as different nanostructures with different forms and sizes. As a second part of this review, the application of their synthetic ability as new heterogonous catalysts has been described in C–C bond-forming reactions (as Suzuki, Heck, cycloaddition or multicomponent), oxidations and dynamic kinetic resolutions. Full article
(This article belongs to the Special Issue Nanoparticles for Catalysis)
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