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151.
Shokoh Parham Dedy H. B. Wicaksono Saeedeh Bagherbaigi Siew Ling Lee Hadi Nur 《中国化学会会志》2016,63(4):385-393
Many nanomaterials can be used as metal oxides (Ti, Ag, Zn, Cu, Mg, Ca, Ce, Yt, Al). Metal oxide nanoparticles have strong antimicrobial properties. The oxides that play a large role as antimicrobial agents can be divided into two major groups based on their mechanism of action i.e., those that involve oxidation and those that inhibit the production of Reactive Oxygen Species (ROS). Previous studies have shown that, toxic metals like silver and titanium, and their metals oxides, employ the ROS‐mediated mechanism that leads to oxidative stress‐related cytotoxicity, cancer, and heart diseases. Oxidative stress further leads to increased ROS production and also delays the cellular processes involved in wound heal‐ ing. Other metal oxide nanoparticles, like Y2O3, CeO2 and Al2O3 act as free radical scavengers. Out of these, aluminium oxide nanoparticles are more effective antimicrobial agents, than the other metal oxide nanoparticles. A combination of Al2O3 and other antimicrobial agents such as TiO2 may act as ideal antimicrobial agents, along with possessing free radical scavenging activity. This critical review aims to study the antimicrobial properties of different metal oxide nanoparticles and the mechanism of action in‐ volved, besides comparing their efficacy to eliminate bacteria. 相似文献
152.
Norbani Abdullah Zainudin Arifin Edward R. T. Tiekink Naima Sharmin Nur Syamimi Ahmad Tajidi Siti Amira Mat Hussin 《Journal of Coordination Chemistry》2016,69(5):862-878
A covalent mononuclear complex, [Cu(p–HOC6H4COO)2(cyclam)] (1), and two ionic mononuclear complexes, [Cu(cyclam)(H2O)2](p–CH3OC6H4COO)2 (2) and [Cu(cyclam)(H2O)2](p–CH3(CH2)15OC6H4COO)2·H2O (3), were formed from reaction of cyclam with [Cu2(p–HOC6H4COO)4(H2O)2], [Cu2(p–CH3OC6H4COO)4(H2O)2] and [Cu2(p-CH3(CH2)15OC6H4COO)4(H2O)2], respectively. These complexes were isolated as purple crystals with molecular structures showing distorted octahedral N4O2 geometry. Complexes 1 and 2 were irreversibly reduced to Cu(I) and oxidized to Cu(III), while 3 was redox inactive. Complex 2 reacted with N-(hexadecyl)isonicotinamide (L) to form [Cu(cyclam)(L)2](p–CH3OC6H4COO)2 (4). These complexes were thermally stable (Tdec > 200 °C for 1–3 and 174 °C for 4). Complexes 3 and 4 behaved as ionic liquids (melting temperatures lower than 100 °C) and exhibited mesomorphism. 相似文献
153.
Norwahyu Jusoh Thiam Leng Chew Kok Keong Lau Azmi Mohd Shariff 《Separation & Purification Reviews》2016,45(4):321-344
In the early stage of membrane technology development in gas separation, utilization of polymeric membranes has gained attention due to their robustness and ease of fabrication. However, the performance of polymeric membranes is limited by the trade-off between permeability and selectivity. Meanwhile, inorganic membrane is capable to exhibit great enhancement in separation performance but unfortunately its fabrication process is hard and costly. Thus, development of mixed matrix membranes (MMMs) by incorporating inorganic fillers into the polymer matrix has become a potential alternative to overcome the limitations of polymeric and inorganic membranes in gas separation. Nevertheless, fabrication of defect-free MMMs with improved separation performance and without compromising the mechanical and thermal stability is extremely difficult and challenging. In the current review paper, various types of inorganic fillers for MMMs fabrication and recent reported efforts to tailor the underlying problems on MMMs fabrication were discussed. The future outlook to advance the performance of MMMs in gas separation especially for CO2/CH4 separation was highlighted. 相似文献
154.
An adsorptive stripping square wave voltammetric (AdSqW) method was developed for the determination of 3-nitrotyrosine (3-NT), a biomarker of in vivo oxidative damage in Alzheimer, ALS, Parkinson’s, cardiovascular diseases and cancer, in some biological fluids. Voltammetric measurements were performed in 0.30 M (pH 9.0) phosphate solution as supporting electrolyte, a reduction peak was observed at–0.487 V (vs. Ag/AgCl–3 M KCl) with a hanging mercury drop electrode by square wave voltammetry. Cyclic voltammetric measurements showed that the current was adsorption-controlled. LOD and LOQ values were as 0.25 and 1.5 nM, respectively, for the AdSqW method. 3-NT was determined in plasma and cerebrospinal fluid using AdSqW method, which allowed to work at low concentrations. Recovery value was measured as 96.3 ± 2.3%. 相似文献
155.
Norashiqin Misni Zurainee Mohamed Nor Rohani Ahmad Nur Raihana Ithnin Ngah Zasmy Unyah 《Molecules (Basel, Switzerland)》2021,26(12)
Essential oils have been widely used as an active ingredient in mosquito repellent products. However, essential oils are highly unstable and prone to degradation when exposed to the environment during storage. Microencapsulation techniques help to maintain the stability of molecules in essential oils that are sensitive to environmental stress, and therefore improve shelf life. In this study, the physical stability and efficacy of a repellent formulation consisting of encapsulated Citrus grandis essential oil (CGEO) were evaluated under different storage conditions over a 12-month period by comparing the formulation with a non-encapsulated formulation. The formulations were both stored under two different storage conditions, i.e., 25 ± 2 °C/60% ± 5% relative humidity (RH) and 40 ± 2 °C/75% RH ± 5%, for 12 months. Droplet size, zeta potential, and pH value were measured after 1, 6, and 12 months of storage to determine their stability. For the study of efficacy, each formulation was tested against Aedes aegypti under laboratory conditions. We found that the microencapsulated formulation’s physical characteristics showed insignificant changes as compared with the non-encapsulated formulation during storage. The microencapsulated formulation demonstrated better repellent effects, sustaining high protection (>80%) for 4 more hours of exposure after 12 months of storage as compared with the non-encapsulated formulation that demonstrated high protection for only an hour post application. Microencapsulation helped to preserve the stability of the formulation, which resulted in high protection being maintained for over 12 months of storage. 相似文献
156.
Gamze G
GER Ümmühan TÜRKYOLU Ezgi Nur GÜREN Süleyman YUR Abdullah Burak KARADUMAN Fatih G
GER Mehmet TEKN Gülmira
ZEK 《Turkish Journal of Chemistry》2021,45(2):387
In the present work, essential oil and fatty acids and extracts obtained from aerial parts of Phlomis linearis Boiss. & Bal. were investigated for chemical composition and biological activities. The phytochemical analyses were conducted with gas chromatography-mass spectrometry/flame ionisation detector (GC-MS/FID) and liquid chromatography-mass spectromtetry (LC-MS/MS) techniques. The extracts and essential oil were studied for α-amylase and acetylcholinesterase activities with two different spectrophotometric methods. Antimicrobial activities of the extracts were investigated by microdilution. The extracts were evaluated in vitro for cytotoxic effects against cancer and normal cell lines by MTT assay. The essential oil (EO) contained α-pinene (12.5%) and β-caryophyllene (10.7%) as main compounds. Palmitic (26.5%) and nonadecanoic acids (26.6%) were determined as fatty acids. Phytochemical analysis of the extracts found phenolic acids, phlinosides, verbascoside, and flavonoids. The extracts and essential oil demonstrated poor α-amylase inhibitory activity. The best acetylcholinesterase inhibitory activity was obtained for diethly ether extract of P. linearis (67.2 ± 3.4%) at 10 mg /mL concentration. Ethyl acetate extract found to be effective against Staphlococcus aureus at a minimum inhibitory concentration (MIC) of 156.26 µg/mL. Diethyl ether extract of P. linearis was active on A549 cell lines with an IC50 = 316 ± 4.16 µg/mL when compared with cisplatin IC50 = 24.43 ± 0.14 µg/mL. To the best of our knowledge, the present work is the first comprehensive report on anti-acetylcholinesterase, anti-α-amylase, and antimicrobial activities, as well as cytotoxic effects of P. linearis. 相似文献
157.
Khalid Saifuddin Zakaria Irnie Azmi W. H. Mohamed W. A. N. W. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1555-1567
Journal of Thermal Analysis and Calorimetry - Hybrid nanofluid is a new revolutionized cooling liquid with improved thermo-physical properties as compared to conventional coolant. This paper... 相似文献
158.
Hairul Hisham Hamzah Nur Hidayah Saleh Bhavik Anil Patel Mohd Muzamir Mahat Saiful Arifin Shafiee Turgut Snmez 《Molecules (Basel, Switzerland)》2021,26(1)
The development of low-cost electrode devices from conductive materials has recently attracted considerable attention as a sustainable means to replace the existing commercially available electrodes. In this study, two different electrode surfaces (surfaces 1 and 2, denoted as S1 and S2) were fabricated from chocolate wrapping aluminum foils. Energy dispersive X-Ray (EDX) and field emission scanning electron microscopy (FESEM) were used to investigate the elemental composition and surface morphology of the prepared electrodes. Meanwhile, cyclic voltammetry (CV), chronoamperometry, electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) were used to assess the electrical conductivities and the electrochemical activities of the prepared electrodes. It was found that the fabricated electrode strips, particularly the S1 electrode, showed good electrochemical responses and conductivity properties in phosphate buffer (PB) solutions. Interestingly, both of the electrodes can respond to the ruthenium hexamine (Ruhex) redox species. The fundamental results presented from this study indicate that this electrode material can be an inexpensive alternative for the electrode substrate. Overall, our findings indicate that electrodes made from chocolate wrapping materials have promise as electrochemical sensors and can be utilized in various applications. 相似文献
159.
Nur Hilwani Ismail Khairul Osman Aini Farzana Zulkefli Mohd Helmy Mokhtar Siti Fatimah Ibrahim 《Molecules (Basel, Switzerland)》2021,26(11)
Gelam honey (GH) is a prized natural product synthesized from the nectar of flowers from Gelam trees (Melaleuca sp.). Gelam is an evergreen tree species that grows in tropical regions such as Malaysia. GH is a multifloral honey with proven antioxidant and anti-inflammatory properties. However, the beneficial effect of GH on female reproductive tissue has yet to be substantiated. Herein, we investigated the effects of GH administration on the uterine and vaginal epithelial thickness of sexually mature Sprague–Dawley rats. Epithelia thickness could be an indicator of an atrophy manifesting as a symptom of a cardio syndrome. Rats were given oral doses of GH in four groups for 14 days; the lowest dose was 0.2 g GH/kg body weight (bw) rat/day and the highest dose was 8 g GH/kg bw rat/day. The physicochemical characteristics of GH were assessed through hydroxymethylfurfural and moisture content determination and sugar identification. GH attenuated the atrophy of the uterine and vaginal epithelia and increased the thickness of the endometrial stroma and endometrial surface endothelial layer. However, the dissonance observed in the effect of GH administration on the vaginal epithelium requires further investigation. Nevertheless, GH may have a strong potential in attenuating uterine and vaginal atrophies. 相似文献
160.
Güven Kuzey Nur Cemaloğlu Reşit Yakut Mehtap Asmafiliz Nuran Kılıç Zeynel Aydın Betül Açık Leyla Hökelek Tuncer 《Research on Chemical Intermediates》2021,47(10):3933-3962
Research on Chemical Intermediates - The N3P3 ring of hexachlorocyclotriphosphazene, N3P3Cl6 (1) (HCCP; trimer), was used significantly as a scaffold for the syntheses of... 相似文献