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71.
Xujiang Yu Xinyi Liu Weijie Wu Kai Yang Rihua Mao Farooq Ahmad Xiaoyuan Chen Wanwan Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(7):2039-2044
The use of X‐rays instead of UV/Vis light to trigger photodynamic therapy, named X‐ray inducible photodynamic therapy, holds tremendous promise due to a high penetration capacity in tissues and is worthy of in‐depth study. In this study, a novel multifunctional nanoagent based on Merocyanine 540‐coupled Gd2(WO4)3:Tb nanoscintillators and the vitalization of its abilities for dual‐modal computed tomography and the magnetic‐resonance‐imaging‐guided synergistic radio‐/X‐ray inducible photodynamic therapy of tumors is reported. Synergistic therapies show a higher tumor growth inhibition efficiency at a lower X‐ray dose than radiotherapy alone. Through this proof‐of‐concept work, a way to tactfully understand and utilize nanoscintillators for cancer theranostics is shown. 相似文献
72.
Brajendra K. Sharma Umer Rashid Farooq Anwar Sevim Z. Erhan 《Journal of Thermal Analysis and Calorimetry》2009,96(3):999-1008
The increasing application of biobased lubricants could significantly reduce environmental pollution and contribute to the
replacement of petroleum base oils. Vegetable oils are recognized as rapidly biodegradable and are thus promising candidates
for use as base fluids in formulation of environment friendly lubricants. Although many vegetable oils have excellent lubricity,
they often have poor oxidation and low temperature stability. Here in, we report the lubricant potential of Moringa oil, which
has 74% oleic acid content and thus possess improved oxidation stability over many other natural oils. For comparison, Jatropha
oil, cottonseed oil, canola oil and sunflower oil were also studied. Among these oils, Moringa oil exhibits the highest thermo-oxidative
stability measured using PDSC and TG. Canola oil demonstrated superior low temperature stability as measured using cryogenic
DSC, pour point and cloud point measurements. The friction and wear properties were measured using HFRR. Overall, it was concluded
that Moringa oil has potential in formulation of industrial fluids for high temperature applications.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
73.
Nazar Mohammad Ranjha Jahanzeb Mudassir Naveed Akhtar 《Journal of Sol-Gel Science and Technology》2008,47(1):23-30
In the present work methyl methacrylate-co-itaconic acid (MMA-co-IA) hydrogels were synthesized by free radical copolymerization
of methyl methacrylate (MMA) and itaconic acid (IA) using ethylene glycol dimethacrylate (EGDMA) and methylene bisacrylamide
(MBAAm) as crosslinkers and benzoyl peroxide as initiator. Selected samples were loaded with model drug lactulose. For the
lactulose release, the effect of pH, monomeric compositions, degree of crosslinking were investigated. The release of lactulose
was studied for 8 h period in USP phosphate buffer solutions of varying pH 1.2, 5.5, 6.5 and 7.0. The drug release data were
fitted into various kinetics models like the zero order, first order, Higuchi and Peppas. The release kinetics of lactulose
from MMA/IA hydrogels was found to be best described by the Peppas model. Results showed that drug release increased by increasing
IA content in the hydrogels but the effect of changing of crosslinking ratio on drug release was not significant. The surface
morphology of MMA/IA drug loaded hydrogel was studied by SEM which revealed uniform distribution of the drug in the hydrogels.
In conclusion, it can be said that lactulose can be successfully incorporated into crosslinked MMA/IA hydrogels and its release
can be modulated by changing the mole fraction of the acid component in the gels. 相似文献
74.
Syed Farooq Adil Mohamed E. Assal Mohammed Rafi Shaik Mufsir Kuniyil Azhar Hashmi Mujeeb Khan Aslam Khan Muhammad Nawaz Tahir Abdulrahman Al-Warthan Mohammed Rafiq H. Siddiqui 《应用有机金属化学》2020,34(8):e5718
Graphene–metal nanocomposites have been found to remarkably enhance the catalytic performance of metal nanoparticle-based catalysts. In continuation of our previous report, in which highly reduced graphene oxide (HRG)-based nanocomposites were synthesized and evaluated, we present nanocomposites of graphene oxide (GRO) and ZnO nanoparticle-doped MnCO3 ([ZnO–MnCO3/(1%)GRO]) synthesized via a facile, straightforward co-precipitation technique. Interestingly, it was noticed that the incorporation of GRO in the catalytic system could noticeably improve the catalytic efficiency compared to a catalyst (ZnO–MnCO3) without GRO, for aerial oxidation of benzyl alcohol (BzOH) employing O2 as a nature-friendly oxidant under base-free conditions. The impacts of various reaction factors were thoroughly explored to optimize reaction conditions using oxidation of BzOH to benzaldehyde (BzH) as a model substrate. The catalysts were characterized using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, Energy dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET), and Raman spectroscopy. The (1%)ZnO–MnCO3/(1%)GRO exhibited significant specific activity (67 mmol.g−1.hr−1) with full convversion of BzOH and >99% BzH selectivity within just 6 min. The catalytic efficiency of the (1%)ZnO–MnCO3/(1%)GRO nanocomposite was significantly better than the (1%)ZnO–MnCO3/(1%)HRG and (1%)ZnO–MnCO3 catalysts, presumably due to the existence of oxygen-possessing groups on the GRO surface and as well as a very high surface area that could have been instrumental in uniformly dispersing the active sites of the catalyst, i.e., ZnO–MnCO3. Under optimum circumstances, various kinds of alcohols were selectively transformed to respective carbonyls with full convertibility over the (1%)ZnO–MnCO3/(1%)GRO catalyst. Furthermore, the highly effective (1%)ZnO–MnCO3/(1%)GRO catalyst could be successfully reused and recycled over five consecutive runs with a marginal reduction in its performance and selectivity. 相似文献
75.
Ali Farooq H. Hamzah Hameed K. Mozaffari Masoud Mehryan S. A. M. Ghalambaz Mohammad 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1801-1816
Journal of Thermal Analysis and Calorimetry - In this study, the heat transfer, fluid flow and heat capacity ratio are analyzed in an annulus enclosure filled with porous and saturated by a... 相似文献
76.
The interaction of the antidepressant drug nortriptyline hydrochloride (NOT) with the surface-active ionic liquid (SAIL), 1-decyl-3-methylimidazolium chloride, [C10mim][Cl], has been studied using multiple techniques, including conductometric titration, tensiometric, fluorometric, dynamic light scattering and UV–visible spectrophotometric measurements. There is a significant decrease in the cmc of SAIL on the addition of the drug NOT, indicating adsorption of drug molecules in the outer portion of the micelle. In the present study, the values of the packing parameter, P, lie in the range of 0–0.3, which suggests that the micelles formed are spherical in nature. More negative values of the standard Gibbs energy of adsorption, \( \Delta G_{\text{ad}}^{ \circ } \), compared to \( \Delta G_{\text{m}}^{ \circ } \) support our contention that adsorption of SAIL on the air-solution interface is relatively more favorable than its micellization in the presence of NOT. Fluorescence and DLS studies indicate that the aggregation number, Nagg, and hydrodynamic radius of SAIL increase with increase in concentration of NOT. The UV–visible spectroscopic study confirms the formation of a new complex between SAIL and NOT; this is also supported by the negative Gibbs energy of complexation. 相似文献
77.
Aiza Azam Gulzar Muhammad Muhammad Shahbaz Aslam Muhammad Mudassir Iqbal Muhammad Arshad Raza Naeem Akhtar Muhammad Ajaz Hussain Noreen Sajjad Asad Syed Ali H. Bahkali Zahid Shafiq 《应用有机金属化学》2023,37(1):e6923
The multifunctional zinc oxide nanoparticles are synthesized using a cost-effective, efficient, eco-friendly, simple, and clean synthesis approach. Herein, we reported the antibacterial and wound healing potential of zinc oxide nanoparticles (ZnO-NPs) prepared using psyllium gel (PG) as the reducing and stabilizing agent. The PG-mediated zinc oxide nanoparticles (PG-ZnO-NPs) were characterized using UV–Vis, photoluminescence (PL), FTIR, XRD, Raman, and SEM. UV–Vis spectral studies confirmed the surface plasmonic resonance (SPR) band at 364 nm. PL results demonstrated the fluorescent or emission nature of PG-ZnO-NPs. FTIR analysis confirmed characteristic peaks at 873.82 and 619.88 cm−1 due to the tetrahedral coordination of zinc and the formation of the Zn-O bond. XRD and Raman confirm the formation of PG-ZnO-NPs, whereas SEM analysis revealed PG-ZnO-NPs are rod-shaped, having hexagonal prism-like bases, and EDX exhibited the elemental composition of PG-ZnO-NPs. The as-synthesized PG-ZnO-NPs possessed prominent microbicidal potential against gram-positive (Bacillus subtilis and Bacillus licheniformis) and gram-negative (Escherichia coli and Salmonella shigella) bacterial strains in terms of zone of inhibition (ZOI), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). In vivo biological investigations with mice show that the synthesized PG-ZnO-NPs possess outstanding biocompatibility and wound healing potential. PG-ZnO-NPs dressing significantly speeds up full-thickness wound repair by triggering a decrease in MMP-1 and MMP-2 and escalating the mRNA levels of collagen types (I & III) and fibronectin. Thus, our work validates that the inclusion of PG-ZnO-NPs in dressing shows excellent potential for acute wound management. 相似文献
78.
Jayachamarajapura Pranesh Shubha Haralahalli Shivappa Savitha Syed Farooq Adil Mujeeb Khan Mohammad Rafe Hatshan Kiran Kavalli Baji Shaik 《Molecules (Basel, Switzerland)》2021,26(15)
Zinc oxide-ternary heterostructure Mn3O4/ZnO/Eu2O3 nanocomposites were successfully prepared via waste curd as fuel by a facile one-pot combustion procedure. The fabricated heterostructures were characterized utilizing XRD, UV–Visible, FT-IR, FE-SEM, HRTEM and EDX analysis. The photocatalytic degradation efficacy of the synthesized ternary nanocomposite was evaluated utilizing model organic pollutants of methylene blue (MB) and methyl orange (MO) in water as examples of cationic dyes and anionic dyes, respectively, under natural solar irradiation. The effect of various experimental factors, viz. the effect of a light source, catalyst dosage, irradiation time, pH of dye solution and dye concentration on the photodegradation activity, was systematically studied. The ternary Mn3O4/ZnO/Eu2O3 photocatalyst exhibited excellent MB and MO degradation activity of 98% and 96%, respectively, at 150 min under natural sunlight irradiation. Experiments further conclude that the fabricated nanocomposite exhibits pH-dependent photocatalytic efficacy, and for best results, concentrations of dye and catalysts have to be maintained in a specific range. The prepared photocatalysts are exemplary and could be employed for wastewater handling and several ecological applications. 相似文献
79.
Hamid Saeed Shah Usman Nasrullah Sumera Zaib Faisal Usman Ajmal Khan Umar Farooq Gohar Jalal Uddin Imtiaz Khan Ahmed Al-Harrasi 《Molecules (Basel, Switzerland)》2021,26(22)
The rapidly growing global burden of cancer poses a major challenge to public health and demands a robust approach to access promising anticancer therapeutics. In parallel, nanotechnology approaches with various pharmacological properties offer efficacious clinical outcomes. The use of new artificial variants of nanosponges (NS) as a transporter of chemotherapeutic drugs to target cells has emerged as a very promising tool. Therefore, in this research, ethylcellulose (EC) NS were prepared using the ultrasonication assisted-emulsion solvent evaporation technique. Withaferin-A (WFA), an active ingredient in Withania somnifera, has been implanted into the nanospongic framework with enhanced anticancer properties. Inside the polymeric structure, WFA was efficiently entrapped (85 ± 11%). The drug (WFA) was found to be stable within polymeric nanosponges, as demonstrated by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) studies. The WFA-NS had a diameter of 117 ± 4 nm and zeta potential of −39.02 ± 5.71 mV with a polydispersity index (PDI) of 0.419 ± 0.073. In addition, scanning electron microscopy (SEM) revealed the porous surface texture of WFA-NS. In vitro anticancer activity (SRB assay) results showed that WFA–NS exhibited almost twice the anticancer efficacy against MCF-7 cells (IC50 = 1.57 ± 0.091 µM), as quantified by flow cytometry and comet tests. Moreover, fluorescence microscopy with DAPI staining and analysis of DNA fragmentation revealed apoptosis as a mechanism of cancer cell death. The anticancer activity of WFA-NS was further determined in vivo and results were compared to cisplatin. The anticancer activity of WFA-NS was further investigated in vivo, and the data were consistent to those obtained with cisplatin. At Day 10, WFA-NS (10 mg/kg) significantly reduced tumour volume to 72 ± 6%, which was comparable to cisplatin (10 mg/kg), which reduced tumour volume to 78 ± 8%. Finally, the outcomes of molecular modeling (in silico) also suggested that WFA established a stable connection with nanosponges, generating persistent hydrophobic contacts (polar and nonpolar) and helping with the attractive delayed-release features of the formulation. Collectively, all the findings support the use of WFA in nanosponges as a prototype for cancer treatment, and opened up new avenues for increasing the efficacy of natural product-derived medications. 相似文献
80.
Muhammad Mohsin Iqbal Muhammad Imran Tousif Hussain Muhammad Asif Naeem Abdullah A. Al-Kahtani Ghulam Mustafa Shah Sajjad Ahmad Amjad Farooq Muhammad Rizwan Abdul Majeed Abdul Rehman Khan Shafaqat Ali 《Journal of Saudi Chemical Society》2021,25(2):101176
Widespread application of dyes and disposal of their untreated effluents into water bodies adversely affect the ecosystem due to their complex aromatic structures and persistent nature. The present study aims to utilize the cotton stalks biochar (CSB) and its composite with zinc oxide nanoparticles (CSB/ZnONPs) to evaluate for the decontamination their batch scale potential of Congo red dye from wastewater. The characterization of CSB and CSB/ZnONPs was performed with Fourier-transform infra-red (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray (EDX) and point of zero charge (PZC) to get insight of their potential for the decontamination of CR. The effects of initial CR concentration (25–500 mg/L), dosage of CSB and CSB/ZnONPs (0.5–2 g/L), solution pH (2–10) and contact time (0–180 min) were evaluated on CR removal at temperature (25 ± 1.5 °C). The results disclosed that CSB/ZnONPs showed excellent adsorption potential (556.6 mg/g) in comparison with CSB (250 mg/g) and most of the other adsorbents previously studies in the literature. The equilibrium experimental data were equally explained with Freundlich and Langmuir isotherm models (R2 > 0.98) while kinetic data demonstrated the best fit with pseudo second order model. The CSB/ZnONPs composite exhibited excellent reusability (89.65%) after five adsorption/desorption cycles for the sequestration of CR from contaminated systems. The present study demonstrated that metallic nanocomposite of CSB (CSB/ZnONPs) is an excellent candidate for the cost effective and environment friendly decontamination of CR from industrial wastewater and is suggested to be considered for the decontamination of other pollutants from the wastewater. 相似文献