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101.
Fluorescence Intensity Enhancement of Green Carbon Dots: Synthesis,Characterization and Cell Imaging
Fatemeh Hashemi Fatemeh Heidari Nasrin Mohajeri Farideh Mahmoodzadeh Nosratollah Zarghami 《Photochemistry and photobiology》2020,96(5):1032-1040
The hydrothermal treatment of green carbon dots (CDs) is an appropriate fluorescent probe synthesis method. CDs are exploited as biological staining agents, especially for cellular detection and imaging. The nitrogen-doped green carbon dots (N-CDs) formation can improve the fluorescence intensity property in a one-step process. Here, we report two N-CDs from lemon and tomato extraction in the presence of hydroxylamine. Lemon and tomato N-CDs showed the blue fluorescence under ultraviolet radiation of about 360 nm. The characterization of CDs and N-CDs showed the presence of N-H and C–N bonds which enhanced the fluorescence efficiency. The mean size of lemon and tomato N-CDs were about 2 and 3 nm with an increased quantum yield (QY) of 5% and 3.38%, respectively. The CDs and N-CDs cytotoxicity assay exhibited high cell viability approximately 85% and 73%, respectively. N-CDs show superior fluorescent intensity in different solvents and significant stability under long-time UV irradiation, different PH and high ionic strength. Our results indicated that the use of N-CDs in cell imaging can lead to fluorescence intensity enhancement as well as proper biocompatibility. Therefore, the safe and high fluorescence intensity of green N-CDs can be utilized for fluorescent probes in biolabeling and bioimaging applications. 相似文献
102.
Nasrin Talebian Monir Doudi Maryam Kheiri 《Journal of Sol-Gel Science and Technology》2014,69(1):172-182
This study presents the characterization and antibacterial activity of nanostructure NiO films synthesized by sol–gel dip coating method using solvents of different polarities and viscosities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvent. The antibacterial activity was tested against two common foodborne pathogenic bacteria Staphylococcus aureus (ATCC 25922) and Escherichia coli (ATCC 29213) using the so-called antibacterial drop test. X-ray diffraction, scanning electron microscopy, atomic force microscopy, UV–vis spectroscopy and static contact angles test were used to analysis the structure and morphology character, surface topography, optical property and surface wettability of different coatings, respectively. The characterization results showed different preferred crystallographic orientations, particle sizes, surface properties and optical band gap of NiO films according to the solvent physicochemical properties. The antibacterial efficiencies were affected by the physiological status of the bacterial cells and degree of bacteria adherence, morphologies and crystal growth habits, surface and optical properties of NiO samples. 相似文献
103.
Sayyed Hossein Hashemi Morteza Ziyaadini Massoud Kaykhaii Ahmad Jamali Keikha Nasrin Naruie 《Journal of separation science》2020,43(2):505-513
By synthesizing a molecular imprinted polymer as an efficient adsorbent, ciprofloxacin was micro‐extracted from seawater, human blood plasma and tablet samples by pipette‐tip micro solid phase extraction and determined spectrophotometrically. Response surface methodology was applied with central composite design to build a model based on factors affecting on microextraction of ciprofloxacin; including volume of eluent solvent, number of extraction cycles, number of elution cycles, and pH of sample. Other factors that affect extraction efficiency, such as type of eluent solvent, volume of sample, type, and amount of salt were optimized with one‐variable‐at‐a‐time method. Under optimum extraction condition, pH of sample solution was 7.0, volume of eluent solvent (methanol) was 200 µL, volume of sample solution was 10 mL, and the number of extraction and elution cycles was five and seven, respectively, amount of Na2SO4 (as salt) and MIP (as sorbent) were optimized at 150 and 2 mg, respectively. The linear range of the suggested method under optimum extraction factors was 5–150 µg/L with a limit of detection of 1.50 µg/L for the analyte. Reproducibility of the method (as relative standard deviation) was better than 7%. 相似文献
104.
Fatemeh Hedayati Nasrin Moshiri‐Gomchi Mahmood Assaran‐Ghomi Sara Sabahi Naeimeh Bahri‐Laleh Shahram Mehdipour‐Ataei Javad Mokhtari‐Aliabad Seyed Amin Mirmohammadi 《先进技术聚合物》2020,31(3):566-573
In order to lower brittleness of biobased polylactic acid (PLA), its blending with polycarbonate and nanosilica is aimed. In this line, to increase compatibility of the ingredients, dicumyl peroxide (DCP) and Cobalt (II) acetylacetonate (Co) were used as grafting and transesterification catalysts, respectively. The X‐ray diffraction (XRD) spectra demonstrated high compatibility of the ingredients by broadening of the PLA characteristic peaks and, also, good dispersion of nanosilica particles, especially in PLA/PC/Silica/Co sample. The EDX maps confirmed good nanosilica dispersion, too. The silica nanoparticle size was ranged from 20 to 100 nm in transmission electron microscopy (TEM) pictures. All nanocomposites showed improved thermal stability in thermogravimetric analysis (TGA). Differential scanning calorimetry (DSC) results demonstrated lower Tg, Tm, and crystallinity values for the fabricated nanocomposites. Notably, the dynamic mechanical thermal analysis (DMTA) curves confirmed the Tg, Tm, and Tcc trend obtained in DSC; moreover, much higher surface under tan δ peak for PLA/PC/Silica/Co sample was obtained, which implies its higher toughness. The precise tensile study of the samples confirmed significantly higher elongation at break of the nanocomposites, more considerably in PLA/PC/Silica/Co sample, with nearly negligible defect on tensile strength and modulus. In a concise, the obtained results confirmed the higher efficiency of Co catalyst, which leads to the sample with improved characteristics compared with DCP. 相似文献
105.
An easy, efficient, and simple one-pot approach for the synthesis of 1,3-thiazolidine-2-thiones via multicomponent reaction is reported. The reaction of a primary amine with carbon disulfide in the presence of dibenzoylacetylene or bis(4-methyl-1-benzoyl)acetylene in a mixture of CH2Cl2 and H2O after 5 h, afforded the title compound as alkene diastereomers. 相似文献
106.
This study investigates a classic stochastic location problem in a service system with immobile servers that are represented by M/G/1 queues. It shows that 相似文献
107.
Polystyrene resin-supported copper(I) iodide-cryptand-22 complex (PS–C22–CuI) was synthesized and characterized by FT-IR, EDX, SEM, XPS, and TG-DTA analysis. This complex was found to be a highly active and robust heterogeneous catalyst for either three-component reaction of organic halides, sodium azide, and terminal alkynes, or the reaction of organic azides and alkynes to form 1,4-disubstituted 1,2,3-triazoles in good to excellent yields at room temperature, using water as the green solvent. The catalyst can be not only easily isolated from the final product by filtration but also reused without significant loss of catalytic activity. 相似文献
108.
Choitanya Dev Pegu Sheikh Benazir Nasrin Mohit L. Deb Deep Jyoti Das Kandarpa K. Saikia 《合成通讯》2017,47(21):2007-2014
CAN-catalyzed reaction of Betti bases with indoles under microwave irradiation gives 3-(α,α-diarylmethyl)indoles. Better yield of the products, especially when one of the aryl ring is phenol were achieved. The reaction is performed in solvent-free condition. The antibacterial studies of the synthesized compounds were performed and some of the compounds showed good activity against Methicillin-resistant Staphylococcus aureus bacteria. 相似文献
109.
In the present work, Cu@KCC-1-NH-CS2 as a green, efficient, and reusable nano-reactor was designed and used for the one-pot, three-component synthesis of 2-amino-4H-chromene derivatives using the reaction of cyclic 1,3-diketones, arylglyoxals, and malononitrile, under reflux conditions in EtOH. Engineered nanocatalyst characterized using different methods including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), adsorption/desorption analysis (BET), and energy dispersive X-ray spectroscopy (EDS). According to the obtained results, presented protocol for the synthesis of 2-amino-4H-chromenes using Cu@KCC-1-NH-CS2 gave the desired products in higher yields (89–98%) with short reaction times. Also, under mild reaction conditions this green nanocatalyst indicated recyclable behavior five times with minor reduce in its catalytic activity. 相似文献
110.
Esfahani Ensieh Nasli Mohammadi-Khanaposhtani Maryam Rezaei Zahra Valizadeh Yosef Rajabnia Ramazan Hassankalhori Mahdi Bandarian Fatemeh Faramarzi Mohammad Ali Samadi Nasrin Amini Mohammad Reza Mahdavi Mohammad Larijani Bagher 《Research on Chemical Intermediates》2019,45(2):223-236
Research on Chemical Intermediates - We designed and synthesized a series of new ciprofloxacin–dithiocarbamate–benzyl hybrids 5a–n as potential antibacterial agents. All of the... 相似文献