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Introduction The current tendency of using oxidic materials as nanoparticles leaded to the permanent development of new unconventional synthesis methods [ 1 – 4 ]. This is due to the different properties of the nanomaterials

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. 29 , 221 – 236 . Anita , S. , Ramachandran, T. , Koushik , C. V. , Rajendran , R. and Mahalakshmi , M. ( 2010 ): Preparation and characterization of zinc oxide nanoparticles and a study of their antibacterial property of cotton fabric

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Journal of Thermal Analysis and Calorimetry
Authors: Grażyna Janowska, Teresa Mikołajczyk, Dorota Wołowska-Czapnik, and M. Boguń

Summary  

The paper discusses the thermal properties of alginate fibres made from alginic acid or sodium alginate and from alginates substituted with divalent metal ions during the fibre-forming stage. Alginate fibres with an addition of silica nanoparticles have also been examined. The selection of fibre-forming parameters was intended to obtain the best either sorption or strength properties depending on the specific fibre application. Thermal curves of the fibres under investigations obtained by under air atmosphere and differential scanning calorimetry (DSC) under neutral gas atmosphere have been interpreted from the view of physical and chemical changes in the fibre-forming material. Based on thermogravimetric curves, the fibre thermal stability indices have been determined. It has been found that the addition of silica nanoparticles exerts a positive influence on the thermal properties of the examined fibres.

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Abstract  

Plasmon-resonant nanoparticles are being integrated into a variety of actuators, sensors and calorimeters due to their extraordinary optical capabilities. We show a continuum energy balance accurately describes thermal dynamics and equilibrium temperatures in plasmon-resonant nanoparticle systems. Analysis of 18 data sets in which temperature increased ≤10.6 °C yielded a mean value of R 2 > 0.99. The largest single relative temperature error was 1.11%. A characteristic temperature was introduced into a linear driving force approximation for radiative heat transfer in the continuum energy description to simplify parameter estimation. The maximum percent error of the linearized description rose to 1.5% for the 18 sets. Comparing the two descriptions at simulated temperature increases up to 76.6 °C gave maximum relative errors ≤7.16%. These results show for the first time that the energy balance and its linearized approximation are applicable to characterize dynamic and equilibrium temperatures for sensors, actuators and calorimeters containing nanoparticles in microfluidic and lab-on-chip systems over a broad range of heat-transfer lengths, power inputs and corresponding temperature increases.

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. Tartaj , P , Morales , MDP , Veintemillas-Verdaguer , S , Gonzáalez-Carreño , T , Serna , CJ . The preparation of magnetic nanoparticles for applications in biomedicine . J Phys D . 2003 ; 36R : 182 – 197 . 10

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, S.H. , Kang , C.B. & Ko , S. ( 2011 ): Preparation of size-controlled bovine serum albumin (BSA) nanoparticles by a modified desolvation method . Food Chem., 127 , 1892 – 1898

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Huan Meng, Zhen Chen, Gengmei Xing, Hui Yuan, Chunying Chen, Feng Zhao, Chengcheng Zhang, Yun Wang, and Yuliang Zhao

Abstract  

Recently, it was reported that the toxicity of copper particles increases with the decrease of the particle size on a mass basis. To understand this phenomenon, inductively coupled plasma mass spectrometry (ICP-MS) techniques and in vitro chemical studies were carried out to explore how they produce toxicity in vivo. The results suggest that when the sizes of particles become small and down to a nanoscale, copper becomes extremely reactive in a simulative intracorporeal environment. The nanosized copper particles consume the hydrogen ions in stomach more quickly than micron ones. These processes further convert the copper nanoparticles into cupric ions whose toxicity is very high in vivo.

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., Laurencin, C. T.: Nanofibers and nanoparticles for orthopaedic surgery applications. J. Bone Joint Surg. Am., 2008, 90 , 128–131. Laurencin C. T. Nanofibers and nanoparticles for

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This study examined the applications of novel non-polymer magnetic ferrite nanoparticles (Fe3O4 NPs) labeled with 99mTc-pertechnetate (99mTcO4 ). The radiochemistry, chemistry, and biodistribution of Fe3O4 NPs labeled with 9mTcO4 were analyzed. This paper employed instant thin layer chromatography and magnetic adsorption to evaluate the labeling efficiency and stability of 99mTc-Fe3O4 at various reaction conditions. A scanning electron microscope, X-ray diffractometer, Fourier transform infrared spectrometer, laser particle size analyzer, and superconducting quantum interference device magnetometer were used to analyze the physical and chemical properties of the Fe3O4 and 99Tc-Fe3O4 nanoparticles. The biodistribution and excretion of 99mTc-Fe3O4 were also investigated. Radiochemical analyses showed that the labeling efficiency was over 92% after 1 min in the presence of a reducing agent. Hydroxyl and amine groups covered the surface of the Fe3O4 particles. Therefore, 99Tc (VII) reduced to lower oxidation states and might bind to Fe3O4 NPs. The sizes of the 99Tc-Fe3O4 NPs were about 600 nm without ultrasound vibrations, and the particle sizes were reduced to 250 nm under ultrasound vibration conditions. Nonetheless, Fe3O4 NPs and 99Tc-Fe3O4 NPs exhibited superparamagnetic properties, and the saturation magnetization values were about 55 and 47 emu/g, respectively. The biodistribution showed that a portion of the 99mTc-Fe3O4 nanoparticles might embolize in a pulmonary capillary initially; the embolism radioactivity was cleared from the lungs and was then taken up by the liver. 99mTc-Fe3O4 metabolized very slowly only 1–2% of the injected dose (ID) was excreted in urine and about 2.37% ID/g was retained in the liver 4 h after injection. Radiopharmaceutically, 99mTc-Fe3O4 NPs displayed long-term retention, and only 99mTc-Fe3O4 NPs that dissociated to free pertechnetate could be excreted in urine. This research evaluated the feasibility of non-polymer magnetic ferrite NPs labeled with technetium as potential radiopharmaceuticals in nuclear medicine.

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Abstract  

Hypocrellins, natural photosensitizers including hypocrellin A (HA) and hypocrellin B (HB), have been used as a traditional Chinese herbal medicine to cure various skin diseases. Hypocrellins have excellent antiviral activity, which can inhibit the growth of human immunodeficiency virus. They also exhibit significant light-induced antitumor property. In this article, thermal analysis technologies (e.g., differential scanning calorimetry and thermogravimetry) are employed to characterize whether the photosensitive hypocrellin A could be encapsulated with silica nanoparticle (SN) material or not, and evaluate the stability of inclusion complex. The results show that the inclusion complex exhibits improved performance in both stability and hydrophilicity than natural hypocrellin A. Fluorescence spectrophotometry studies have also been performed to verify the thermal analysis results. The results suggest that the thermal analysis technology could be used as an effective and rapid tool to characterize the encapsulation properties of the novel anticancer HA–SN complex.

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