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121.
Abdulla-Al-Mamun M Kusumoto Y Zannat T Islam MS 《Physical chemistry chemical physics : PCCP》2011,13(47):21026-21034
The photocatalytic and plasmonic photothermal cancer cell-killing activity of the metallic Au-capped TiO(2) (Au@TiO(2)) composite colloidal nanopellets has been investigated on HeLa cells under UV-visible (350-600 nm) light irradiation. The Au@TiO(2) composite nanopellets with the uniform Au-capped TiO(2) structure were successfully synthesized by simple reduction of HAuCl(4) on the surface of TiO(2) nanoparticles. The morphological structure and surface properties of Au@TiO(2) were characterized by using UV-visible absorption spectroscopy, TEM, SEM, XPS, EDX and XRD analyses. The formation of hydroxyl radicals (˙OH) was confirmed by photoluminescence (PL) spectra. The photocatalytic and photothermal cell-killing activity of the Au@TiO(2) nanopellets was found to vary with the molar ratio of Au to TiO(2). The direct involvement of the metal particles in mediating the electron transfer from the photoexcited TiO(2) under the band gap excitation is considered to carry out the efficient photocatalytic reaction on the cells. The plasmonic absorption spectra of Au@TiO(2) suspensions were also measured for the evaluation of photothermal cell killing. The charge separation, the interfacial charge-transfer and photothermal activity promoted the photocatalytic-photothermal cancer-cell killing more than TiO(2) alone. The cytotoxic effect of Au@TiO(2) nanopellets with low concentration of gold (TiO(2) : Au molar ratio > 1 : 1) was found to be 100%, whereas that of the commercial TiO(2) (P25) was ca. 50%. The comparative study of the cell viability using Au alone and TiO(2) alone revealed that the synergistic effect of photocatalytic hydroxyl radical formation and Au-plasmonic photothermal heat generation plays a vital role in the cancer cell killing. A plausible mechanism was also proposed for photocatalytic cancer cell killing based on the obtained results. 相似文献
122.
Matthew Monari Ombaba V. J. Logeeswaran M. Saif Islam 《Applied Physics A: Materials Science & Processing》2013,111(1):251-259
In this paper we report a novel application of electrically conductive film (ECF) of Ag sub-micron particles that includes both isotropic and anisotropic film technologies in providing simultaneous electrical contact and mechanical anchor between fracture transfer-printed (1-D) single crystal semiconductor micro- and nano-pillars and a carrier substrate. We assembled silver sub-micron particles (AgSP) monolayers with varying particle diameters and investigated their optical and electrical characteristics prior to their incorporation into thermoplastic polymers. It was found that transfer-printing of the Si micropillar arrays, into electrically conductive thermoplastic receiver substrates, made of films of AgSP/PMMA blends atop metallic substrates could be effectively achieved to yield electrically interfaced 1-D Si micropillar arrays with retention of their orientation and integrity according to the SEM images. The carrier substrate can potentially be reused to generate additional Si micropillar arrays that can be similarly harvested. 相似文献
123.
124.
Mohamed Morsy Ahmed I. Abdel-Salam Islam Gomaa Hesham Moustafa Haitham Kalil Ahmed Helal 《Molecules (Basel, Switzerland)》2023,28(1)
The demand for reactive dyes in industries has increased rapidly in recent years, and producing a large quantity of dye-containing effluent waste contaminates soils and water streams. Current efforts to remove these harmful dyes have focused on utilizing functionalized nanomaterials. A 3D polyurethane foam loaded with reduced graphene oxide (rGO) and ZnO nanocomposite (PUF/rGO/ZnO) has been proposed as an efficient structural design for dye degradation under the influence of visible light. The proposed structure was synthesized using a hydrothermal route followed by microwave irradiation. The resultant 3D PUF/rGO/ZnO was examined and characterized by various techniques such as XRD, FTIR, SEM, EDAX, BET, and UV–visible spectroscopy. SEM data illustrated that a good dispersion and embedment of the rGO/ZnO NPs within the PUF matrix occurred. The adsorption capacity for neat PUF showed that around 20% of the Methylene blue (MB) dye was only adsorbed on its surface. However, it was found that an exceptional adsorption capacity for MB degradation was observed when the rGO/ZnO NPs inserted into the PUF, which initially deteriorated to ~ 70 % of its initial concentration. Notably, the MB dye was completely degraded within 3 h. 相似文献
125.
Nagaraja Sreeharsha Samathoti Prasanthi Satyavarapu Veera Venkata Naga Satya Mahalakshmi Prakash S. Goudanavar Nimbagal Raghavendra Naveen Buduru Gowthami Santosh Fattepur Girish Meravanige Syed Mohammed Basheeruddin Asdaq Md. Khalid Anwer Bandar Aldhubiab Mohammed Monirul Islam Mohammed Habeebuddin Mallikarjun Telsang Mazen Al Gharsan Michelyne Haroun 《Molecules (Basel, Switzerland)》2022,27(22)
A brand-new nano-crystal (NC) version of the hydrophobic drug Paclitaxel (PT) were formulated for cancer treatment. A stable NC formulation for the administration of PT was created using the triblock co-polymer Pluronic F127. To achieve maximum entrapment effectiveness and minimal particle size, the formulation was improved using the central composite design by considering agitation speed and vacuum pressure at five levels (coded as +1.414, +1, 0, −1, and −1.414). According to the Design Expert software’s predictions, 13 runs were created and evaluated for the chosen responses. The formulation prepared with an agitation speed of 1260 RPM and a vacuum pressure of 77.53 mbar can meet the requirements of the ideal formulation in order to achieve 142.56 nm of PS and 75.18% EE, according to the level of desirability (D = 0.959). Folic acid was conjugated to Pluronic F127 to create folate receptor-targeted NC. The drug release profile of the nano-crystals in vitro demonstrated sustained release over an extended period. Folate receptor (FR)-targeted NC (O-PT-NC-Folate) has also been prepared by conjugating folic acid to Pluronic F127. MTT test is used to validate the targeting efficacy on the FR-positive human oral cancer cell line (KB). At pharmacologically relevant concentrations, the PT nano-crystal formulation did not cause hemolysis. Compared to non-targeted NC of PT, the O-PT-NC-Folate showed a comparable but more sustained anti-cancer effect, according to an in vivo anti-tumor investigation in NCI/ADR-RES cell lines. The remarkable anti-tumor effectiveness, minimal toxicity, and simplicity of scale-up manufacturing of the NC formulations indicate their potential for clinical development. Other hydrophobic medications that are formulated into nano-systems for improved therapy may benefit from the formulation approach. 相似文献
126.
Jing Yan Takumi Sakamoto Ariful Islam Yashuang Ping Soho Oyama Hiroyuki Fuchino Hitomi Kawakami Kayo Yoshimatsu Tomoaki Kahyo Mitsutoshi Setou 《Molecules (Basel, Switzerland)》2022,27(20)
The global population is aging, and intervention strategies for anti-aging and the prevention of aging-related diseases have become a topic actively explored today. Nicotinamide adenine dinucleotide (NAD+) is an important molecule in the metabolic process, and its content in tissues and cells decreases with age. The supplementation of nicotinamide mononucleotide (NMN), an important intermediate and precursor of NAD+, has increased NAD+ levels, and its safety has been demonstrated in rodents and human studies. However, the high content of NMN in natural plants has not been fully explored as herbal medicines for drug development. Here, we identified that the leaf of Cinnamomum verum J. Presl (C. verum) was the highest NMN content among the Plant Extract Library (PEL) with food experience, using ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). To validate this result, the extraction and quantitative analysis of bark, leaf, root, and stem of fresh C. verum was conducted. The results revealed that the bark had the highest NMN content in C. verum (0.471 mg/100 g). Our study shed light on the prospects of developing natural plants in the context of NMN as drugs for anti-aging and prevention of aging-related diseases. The future should focus on the development and application of C. verum pharmaceutical formulations. 相似文献
127.
A theoretical investigation at density-functional level of Li ion conduction at the interfaces in Li2O:B2O3 nanocomposites is presented. The structural disorder at the Li2O(111):B2O3(001) interface leads to reduced defect formation energies for Li vacancies and Frenkel defects compared to Li2O surfaces. The average activation energy for Li+ diffusion in the interface region is in the range of the values for Li2O. It is therefore concluded that the enhanced Li conductivity of Li2O:B2O3 nanocomposites is mainly due to the increased defect concentration. 相似文献
128.
S. Islam 《Nuclear Physics B》1973,59(2):600-610
The validity and consistency of the Morrison rule for the process ππ→πA2 is considered at asymptotic energy in the context of the ABFST multiperipheral model. The Morrison rule turns out to be inconsistent with the model. 相似文献
129.
W. V. Prestwich M. A. Islam T. J. Kennett 《Zeitschrift für Physik A Hadrons and Nuclei》1984,315(1):103-111
Values or upper limits for the radiative widths of 12 primaryE2 transitions observed in thermal neutron capture for nuclei with 144≦A≦180 are presented. The results are compared with the predictions of the Axel-Brink hypothesis using the systematics of the isoscalar and isovector quadrupole resonances. The strengths are on the average lower than expected. Analysis of previously reported average resonance data results in the same conclusion. 相似文献
130.
Results of an analysis of the fluctuations observed in the neutron total cross sections of nine different nuclei in the energy range between 1.0 and 2.0 MeV are presented. It has been found that in general these may be explained to be due to fluctuations in the widths and spacings of the compound-nucleus level. The cross section data for some of the nuclei seem to indicate the presence of structures with widths much larger than the compound-nucleus width. 相似文献