but the aspect ratio of ZnO nanorods enlarged while ..

A schematic diagram to interpret electrospinning of polymer nanofibers is shown in Fig
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high-throughput, high-aspect-ratio ..

While plasmonic photo thermal therapy (PPTT( as local hyperthermia could act at a high temperature (56°C), It shows more specificity and a shorter time of heating in comparison to traditional (local, regional, and whole body) hyperthermia. But In order to use this advantage, some critical properties of three key parts of PPTT i.e. laser, nanoparticles and tissue condition need optimization. Herein relation between laser power and nanoparticle concentration to induce and stabilize temperatures in phantom is investigated. Gold nanorods as plasmonic nanoparticles were synthesized, purified and coated with silica. Sign characterization shown Nanorods with a length of 40nm, a width of 10.5nm and about 18nm silica coat Plasmon peak was observed at 812nm. Polyacrylamide gels were selected as tissue-equivalent materials. Different concentrations of SiGNR were mixed with polyacrylamide gels. Laser irradiation was done by diode laser 810 nm with power density of 2W/cm2 for 2 min. Laser power density and nano particle concentration were selected as variable parameters. Thermal changes were monitored online and recorded by an infrared camera. The results show that lower concentrations of SiGNR are more suitable for producing uniform thermal distributions in phantoms, while reducing the laser power decreases the heating rate but thermal distribution is not completely uniform. Frequently turning the laser on/off could induce and stabilize suitable temperature ranges. uniform thermal distribution in tumor, heating rate and prepared constant defined temperature for defining time are three qualitative parameters that need optimization during plasmonic photo thermal therapy. Laser, plasmonic nano particles and tissue are three players of PPTT that must optimize so sufficient heat (qualitative and quantitative) prepares against tumor with the least affect toward healthy tissue.

Themed collection Rising Stars and Young Nanoarchitects in Materials Science ..
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as catalysts due to their high surface-to-volume ratio compared to ..

Figure a shows time-dependent absorption spectra of the reduction with the obtained gold nanoparticles. The results showed that the KGM-capped gold nanoparticles can successfully catalyze the reduction reaction. It could be observed that the reaction was almost completed within 600 s in the presence of NaBH4 (Figure a). Since the concentration of sodium borohydride far exceeds the concentration of 4-NP, the reduction rate can be assumed to be independent of the borohydride concentration. In this context, a pseudo-first-order rate could be used to evaluate the kinetic reaction rate of the current catalytic reaction. Figure b shows the plot of ln At/A0 and At/A0 versus time. ln At/A0 decreased linearly with reaction time, indicating that the reduction reaction follows first-order kinetics. The first-order rate constant was calculated to be 6.03×10-3 s-1, and this value shows that the AuNPs prepared here with KGM possess better catalytic activity compared to other polysaccharides and some extracts (Table ). In addition, the rate constant is comparable to that of other biologically synthesized gold nanoparticle catalysts for the reduction of 4-NP in the presence of NaBH4. The catalysis of the gold nanoparticles is possibly due to the efficient electron transfer from the BH4- ion to nitro compounds mediated by the nanoparticles. This could be attributed to the higher driving force of particle-mediated electron transfer caused by their large Fermi level shift in the presence of highly electron-injecting species such as borohydride ions.

Non-destructive quantification of alignment of nanorods ..
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The success of PPTT is dependent upon the laser, nanoparticles and cells or tissue interaction. If there is an optimum concentration of nanoparticles and laser parameters for specific tumors, then maximum cell death and minimum side effects will be achieved. Thermal distribution is one of the effective qualitative parameters for thermal therapy that should be optimized. Delivering sufficient and targeted laser to elicit the plasmon particles within deeper and spatially distributed tumor environments is important. For reaching to these purposes and decreasing the effects of healthy tissue on laser absorption/scattering, Bagley and coworkers 40 designed biocompatible, implanted illumination devices that unlike the fiber optics could deliver NIR laser broadly to the large surfaces of deep tumors such as ovarian cancers40. GNR as plasmonic nano particle should pass some criteria such as surface modification and having specific size and plasmon peak. Silica layer used for surface modification because it could decrease toxicity and increase photo stability of CTAB coated GNR, silica layer protects gold nano rods from aggregation in phantom or cell growth media, modification and functionalization of SiGNR is easier than bear GNR. For investigation this correlation between GNR and laser parameter for heat production, we need some things simpler than tissue or tumors. Because using actual tissue may be impractical due to the constraints of accessibility and storage of fresh samples. Reproducibility of results may also be poor because of the difficulty in finding identical specimens or sample preparations25. However In order to decrease the complexity of tissue and increase the reproducibility of the result, polyacrylamide gels were selected as the tissue-equivalent phantom. Herein we investigate the correlation of the concentration of silica coated gold nanorods (SiGNR) and laser parameters for preparing sufficient homogenous heat in phantom as a tissue simple model. Gold nanorods were synthesized, purified and coated with a thin layer of silica. Before and after coating they were characterized by TEM and spectrophotometry. SiGNRs were dispersed in polyacrylamide gels phantom. Laser irradiations were done for 2 min by 810 nm CW laser. Temperature changes were monitored online by an infrared camera. Data were extracted by IR analytic software, and the results presented as a thermal image (qualitative) and heating rate graph (quantities) data.

Microfluidic Synthesis of Polymer and Inorganic Particulate Materials
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