Search

The development of a simplified theranostic system with high-efficiency for multifunctional imaging-guided photodynamic therapy/photothermal therapy (PDT/PTT) is a great challenge. Therefore, a versatile fabrication strategy was introduced to design new Fe3O4-black TiO2 nanocomposites (Fe–Ti NCs). The Fe–Ti NCs exhibit an intense broad light absorption, high photothermal conversion efficiency, inherited phototherapy, and favorable magnetic resonance imaging (MRI) properties. The in vitro results demonstrate synergistic PTT and PDT capability of Fe–Ti NCs under 808 nm irradiation at low concentration and power density. Fe–Ti NCs also show superior phototherapy performance (PTT/PDT) under 671 nm laser irradiation. The confocal microscopy analysis demonstrates reactive oxygen species (ROS)-mediated synergistic phototherapy. Hematological and histological analysis confirms no evident toxicity of Fe–Ti NCs. The in vivo photoinduced tumor ablation capability of Fe–Ti NCs was assessed and monitored, and a rapid increase in temperature (60 ± 2 °C) after being exposed to 808 nm laser at 0.7 W cm−2 for 5 min was observed. Then, the same change in temperature is observed under 671 nm laser at 0.5 W cm−2. Thus, in vitro and in vivo dual-wavelength laser tumor ablation ability of Fe–Ti NCs verified excellent synergistic phototherapy efficacy against tumors. Moreover, Fe–Ti NCs exhibit superparamagnetic behavior, high magnetization value (48 emu g−1), good r2 relaxivity value (38.2 mM−1 s−1), and excellent T2 imaging capability to monitor therapeutic performance. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) has emerged as one of the promising cancer therapy approaches. However, nanoparticles (NPs) which are used for PTT might be biopersistent and potentially toxic. The current research explores the promising use of Fe3O4 nanoflowers as nontoxic, efficient photothermal, and strong T2 type magnetic resonance imaging (MRI) contrast agents for imaging-guided photothermal cancer therapy. In this study, a facile solvothermal method is used to fabricate PEG-coated Fe3O4 nanoflowers with controllable dimensions. Their successful fabrication, the effect of the reaction parameters, and their magnetic properties are investigated in depth. The therapeutic performance of the Fe3O4 nanoflowers (Fe-NFs) is evaluated and compared with commercially available black TiO2 nanoparticles (b-TiO2) under an 808 nm laser. The photothermal therapy efficiency of the Fe-NFs is observed to be better than that of the reported Fe3O4 nanoparticles. In vitro and in vivo investigation demonstrates that the therapeutic performance of the Fe-NFs is comparable to that of b-TiO2. Moreover, the Fe-NFs show excellent magnetic properties and magnetic resonance imaging capability to monitor therapeutic performance. [ABSTRACT FROM AUTHOR]

Salmonella enterica serotype Typhi (S. Typhi) is the causative agent of typhoid fever and remains a major health threat in most of the developing countries. The prompt diagnosis of typhoid directly from the patient's blood requires high level of sensitivity and specificity. Some of us were the first to report PCR based diagnosis of typhoid. This approach has since then been reported by many scientists using different genomic targets. Since the number of bacteria circulating in the blood of a patient can be as low as 0.3 cfu ml−1, there is always a room for improvement in diagnostic PCR. In the present study, the role of different types of nanoparticles was investigated to improve the existing PCR based methods for diagnosis and strain typing of S. Typhi (targeting Variable Number of Tandem Repeats [VNTR]) by using optimized PCR systems. Three different types of nanoparticles were used i.e., citrate stabilized gold nanoparticles, rhamnolipid stabilized gold and silver nanoparticles, and magnetic iron oxide nanoparticles. The non-specific amplification was significantly reduced in VNTR typing when gold and silver nanoparticles were used in an appropriate concentration. More importantly, the addition of nanoparticles decreased the non-specificity to a significant level in the case of multiplex PCR thus further validating the reliability of PCR for the diagnosis of typhoid. [ABSTRACT FROM AUTHOR]

Highly efficient visible-light-driven WO3/Fe2(WO4)3·10.7H2O porous microplates have been fabricated for the first time by a simple one-step hydrothermal method using sodium tungstate and iron chloride as precursors. The photocatalyst was characterized by employing X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-VIS absorption, photoluminescence (PL), and Fourier transform infrared spectroscopy (FTIR). From the FESEM and TEM analysis, the size of as-prepared porous microplates was estimated to be ca. 2 μm. The as-prepared sample maintained a high specific surface area (96.906 m2 g−1) and showed remarkably high photocatalytic performance (k = 0.06771 min−1) for the degradation of methyl orange (MO) under visible light irradiation. The improved performance of the product was found to be 3.3 times greater than pure WO3 and about 6.7 times greater than that of P25 TiO2. The enhanced optical absorption in the visible region, large specific surface area, suitable band position and efficient separation of photogenerated electron–hole pairs at the heterojunction interface between the two materials were the key factors involved in the enhancement of the photocatalytic activity. [ABSTRACT FROM AUTHOR]

We have developed a facile, scaled up, efficient and morphology-based novel WO3–g-C3N4 photocatalyst with different mass ratios of WO3 and g-C3N4. It was used for the photodegradation of rhodamine B (RhB) under visible light irradiation and it showed excellent enhanced photocatalytic efficiency as compared to pure g-C3N4 and WO3. The apparent performance of the composite/hybrid was 3.65 times greater than pure WO3 and 3.72 times greater than pure g-C3N4 respectively, and it was also found to be much higher than the previously reported ones. Furthermore, the optical properties of composite samples were evaluated. The bandgap of composite samples lies in the range of 2.3–2.5 eV, which was favourable for photodegradation. The possible mechanism for enhanced catalytic efficiency of the WO3–g-C3N4 photocatalyst is discussed in detail. It was found that the enhanced performance is due to the synergistic effect between the WO3 and g-C3N4 interface, improved optical absorption in the visible region and suitable band positions of WO3–g-C3N4 composites. [ABSTRACT FROM AUTHOR]

Well controlled nanosheets-based hierarchical microspheres (NSHMS) of pure covellite phase CuS were synthesized using a facile PVP assisted solvothermal process. The reaction conditions were optimized using various amounts of PVP to develop unique hierarchical structured hollow microspheres. CuS hollow structures have a bandgap of ~1.97 eV. These mesoporous structures exhibit excellent photocatalytic activity in degradation of organic dyes (Methylene Blue) under natural light in comparison to other structures of copper sulphide. These photocatalysts show extraordinary reusability with over 96.5% degradation of organic dye after 6th cycle. A "bottom-up" assembly was successfully developed to synthesize hollow microspheres with unique and well defined architectures at large scale, which offer a good opportunity to understand the fundamental significance of unusual and complex hierarchical structures for their potential applications. [ABSTRACT FROM AUTHOR]

We report the synthesis of ZnV2O4 spinel oxide novel nanosheets via a template free route to explore its potential hydrogen storage properties for the first time. 2D layered nanostructures are excellent candidates for storage applications. This attracted our interest to synthesize novel spinel oxide nanosheets (NSNs) of ZnV2O4. The maximum value for hydrogen absorption in ZnV2O4 nanosheets at 473 K is 1.36 wt.% and 1.74 wt.% at 573 K, respectively. Our hydrogen storage measurements along ZnV2O4 reveal its superiority over previous reports on hydrogen absorption values concerning oxides, nitrides and chalcogenides. To understand the rate-limiting mechanism, various kinetics models are applied. The calculations show that kinetics is governed by 3D growth with constant interface velocity. The measurements point to ZnV2O4 spinel oxide as a promising hydrogen storage material. PL measurements demonstrate the potential for violet/blue optoelectronic devices. [ABSTRACT FROM AUTHOR]

3-D flower like CoNi alloys nanostructures composed of nanorods have been synthesized by template free hydrothermal method at relatively low temperature (120 °C). The detailed characterizations confirm the formation of good crystalline fcc CoNi alloy, average crystallite size of 18.8 ± 1.0 nm, lattice parameter of 3.531 ± 0.01 Å, and the nearly equiatomic composition (Co50Ni50). Highly uniform flower like nano structures are built up with nanorod of diameter about 100 nm and length in range of 200–400 nm. The nanorods (building blocks of flower) have single crystalline nature with [111] preferred growth direction. The concentration of NaOH plays a vital role in formation of alloys and high concentration promotes the formation of CoNi alloy at low temperature. The concentration of NaOH also affects the morphology remarkably by changing the growth/reaction rate of CoNi nanostructures and results in hollow spheres to nanoplate flower of CoNi alloys. Based on the evolution of the morphology of the products, a step wise growth mechanism is rationally proposed for flower like nanostructures by considering the effects of kinetic parameters on growth. Magnetic measurements show Co50Ni50 flower like nanostructure have high saturation magnetization, coercivity, remanent magnetization, and high effective anisotropy constant of value 101.3 emu g−1, 210.5 Oe, 16.2 emu g−1, and 4.457 × 104 J m−3 respectively. The enhancements of coercivity and effective anisotropy constant are attributed to nanoscale effects such as shape/surface anisotropy. [ABSTRACT FROM AUTHOR]

Hollow core–shell η-Fe2O3microspheres exhibit not only superior electrochemical performance as lithium storage electrodes but also excellent sensitivities to trace levels of gases. [ABSTRACT FROM AUTHOR]

The development of a simplified theranostic system with high-efficiency for multifunctional imaging-guided photodynamic therapy/photothermal therapy (PDT/PTT) is a great challenge. Therefore, a versatile fabrication strategy was introduced to design new Fe 3 O 4 -black TiO 2 nanocomposites (Fe-Ti NCs). The Fe-Ti NCs exhibit an intense broad light absorption, high photothermal conversion efficiency, inherited phototherapy, and favorable magnetic resonance imaging (MRI) properties. The in vitro results demonstrate synergistic PTT and PDT capability of Fe-Ti NCs under 808 nm irradiation at low concentration and power density. Fe-Ti NCs also show superior phototherapy performance (PTT/PDT) under 671 nm laser irradiation. The confocal microscopy analysis demonstrates reactive oxygen species (ROS)-mediated synergistic phototherapy. Hematological and histological analysis confirms no evident toxicity of Fe-Ti NCs. The in vivo photoinduced tumor ablation capability of Fe-Ti NCs was assessed and monitored, and a rapid increase in temperature (60 ± 2 °C) after being exposed to 808 nm laser at 0.7 W cm -2 for 5 min was observed. Then, the same change in temperature is observed under 671 nm laser at 0.5 W cm -2 . Thus, in vitro and in vivo dual-wavelength laser tumor ablation ability of Fe-Ti NCs verified excellent synergistic phototherapy efficacy against tumors. Moreover, Fe-Ti NCs exhibit superparamagnetic behavior, high magnetization value (48 emu g -1 ), good r 2 relaxivity value (38.2 mM -1 s -1 ), and excellent T 2 imaging capability to monitor therapeutic performance.

Photothermal therapy (PTT) has emerged as one of the promising cancer therapy approaches. However, nanoparticles (NPs) which are used for PTT might be biopersistent and potentially toxic. The current research explores the promising use of Fe 3 O 4 nanoflowers as nontoxic, efficient photothermal, and strong T 2 type magnetic resonance imaging (MRI) contrast agents for imaging-guided photothermal cancer therapy. In this study, a facile solvothermal method is used to fabricate PEG-coated Fe 3 O 4 nanoflowers with controllable dimensions. Their successful fabrication, the effect of the reaction parameters, and their magnetic properties are investigated in depth. The therapeutic performance of the Fe 3 O 4 nanoflowers (Fe-NFs) is evaluated and compared with commercially available black TiO 2 nanoparticles (b-TiO 2 ) under an 808 nm laser. The photothermal therapy efficiency of the Fe-NFs is observed to be better than that of the reported Fe 3 O 4 nanoparticles. In vitro and in vivo investigation demonstrates that the therapeutic performance of the Fe-NFs is comparable to that of b-TiO 2 . Moreover, the Fe-NFs show excellent magnetic properties and magnetic resonance imaging capability to monitor therapeutic performance.

Hollow core-shell eta-Fe(2)O(3) microspheres exhibit not only superior electrochemical performance as lithium storage electrodes but also excellent sensitivities to trace levels of gases.