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1.
In recent days, the green synthesized nanomagnetic biocomposites have been evolved with tremendous potential as the future biological agents. This has encouraged us to design and synthesis of a novel Cu NPs supported Thyme flower extract modified magnetic nanomaterial (Fe3O4/Thyme-Cu). It was meticulously characterized using advanced analytical techniques like FT-IR, FESEM, TEM, EDX, VSM, XRD and ICP-OES. After the characterization, the synthesized Fe3O4/Thyme-Cu nanocomposite was engaged in biological assays like study of anti-oxidant properties by DPPH mediated free radical scavenging test using BHT as a reference molecule. Thereafter, on having a significant IC50 value in radical scavenging assay, we extended the bio-application of the desired nanocomposite in anticancer study of A549, Calu6 and H358 human lung cell lines in-vitro through MTT assay. They had very low cell viability and high anti-human lung cancer activities dose-dependently against A549, Calu6 and H358 cell lines without any cytotoxicity on the normal cell line (MRC-5). The IC50 of Fe3O4/Thyme-Cu nanocomposite was 124, 265, and 181 µg/mL against A549, Calu6 and H358 cell lines, respectively. Maybe significant anti-human lung cancer potentials of Fe3O4/Thyme-Cu nanocomposite against common lung cancer cell lines are related to their antioxidant activities. So, these results suggest that synthesized Fe3O4/Thyme-Cu nanocomposite as a chemotherapeutic nanomaterial have a suitable anticancer activity against lung cell lines.  相似文献   

2.
In that work, we have described the synthesis of novel Cu NPs decorated polyethylene glycol (PEG2000) coated magnetic nanoparticles (Fe3O4/PEG2000/Cu NPs) in an eco-friendly pathway applying Green Tea extract as reducing/stabilizing agent. The morphological and physicochemical features of the prepared nanocomposite were determined using several advanced techniques like ICP-OES, FE-SEM, EDX, atomic mapping, TEM, VSM, and XRD studies. In the antioxidant test, the IC50 of Fe3O4/PEG2000/Cu nanocomposite and BHT against DPPH free radicals were 198 and 85 µg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with Fe3O4/PEG2000/Cu nanocomposite were assessed by MTT assay for 48 h about the cytotoxicity and anti-human gastric cancer properties on normal (HUVEC) and gastric cancer cell lines i.e. NCI-N87 and MKN45. The IC50 of Fe3O4/PEG2000/Cu nanocomposite were 316 and 131 µg/mL against NCI-N87 and MKN45 cell lines, respectively. The viability of malignant gastric cell line reduced dose-dependently in the presence of Fe3O4/PEG2000/Cu nanocomposite. It seems that the anti-human gastric cancer effect of recent nanoparticles is due to their antioxidant effects.  相似文献   

3.
This work describes an eco-friendly approach for in situ immobilization of Au nanoparticles on the surface of Fe3O4 nanoparticles, with the help of Thymbra spicata extract and ultrasound irradiations, without using any toxic reducing and capping agents. The combination of Fe3O4 NPs and Au NPs in one hybrid nanostructure (Fe3O4@Thymbra spicata/Au NPs) represents a promising strategy for targeted biomedical applications. The structure, morphology, and physicochemical properties were characterized by various analytical techniques such as fourier transformed infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP) and vibrating sample magnetometer (VSM). MTT assay was used on common ovarian cancer cell lines i.e., SW-626, PA-1, and SK-OV-3 to survey the cytotoxicity and anti-ovarian cancer effects of Fe3O4@Thymbra spicata/Au NPs. The best results of cytotoxicity and anti-ovarian cancer properties were seen in the concentration of 1000 µg/mL. Fe3O4@ Thymbra spicata/Au NPs had very low cell viability and high anti-ovarian cancer activities dose-dependently against PA-1, SW-626, and SK-OV-3 cell lines without any cytotoxicity on the normal cell line (HUVEC). For investigating the antioxidant properties of Fe3O4@ Thymbra spicata/Au NPs, the DPPH test was used in the presence of butylated hydroxytoluene as the positive control. Fe3O4@Thymbra spicata/Au NPs inhibited half of the DPPH molecules in the concentration of 107 µg/mL. Maybe significant anti-human ovarian cancer potentials of Fe3O4@Thymbra spicata/Au NPs against common human ovarian cancer cell lines are linked to their antioxidant activities. After confirming the above results in the clinical trial researches, this formulation can be administrated for the treatment of several types of human ovarian cancers in humans.  相似文献   

4.
In this study, silver nanoparticles (Ag NPs) were decorated on the surface of magnetic nanoparticles in an eco-friendly pathway applying Mentha extract as reducing/stabilizing agent. The morphological and physicochemical features of the prepared Ag/Fe3O4nanocomposite were determined using several advanced techniques. Hence, our protocol is green and advantageous in terms of- i) biochemical modified biocompatible nanocomposite; ii) nanomaterial providing high surface area and larger number reactive sites; iii) very simplistic synthetic procedure; vi) very low load of metal in the composite and v) high yield in short time. In the medicinal part, the anticancer properties of Ag/Fe3O4 nanocomposite against lung cancer cell lines were determined. The free radical for the antioxidant effects was DPPH. The IC50 of Ag/Fe3O4 nanocomposite was 200 µg/ml in the antioxidant test. The IC50 of the Ag/Fe3O4 nanocomposite were 183, 176, 169, and 125 µg/mL against lung cancer (NCI-H661, NCI-H1975, NCI-H1573, and NCI-H1563) cell lines, respectively. In addition, the current study offer that Ag/Fe3O4 nanocomposite could be a new potential adjuvant chemopreventive and chemotherapeutic agent against cytotoxic cells.  相似文献   

5.
In current nanoscience bioengineered magnetic nanoparticles (NPs) have come into prominence with considerable impact. These advanced functional materials find outstanding applications in chemical science in catalysis, environmental issues, sensing etc, as well as in biology as drug delivery agent, chemical therapeutics and others. We have been prompted to architect and synthesize a novel Au NP adorned over chitosan-biguanidine polyplex modified core–shell type magnetic nanocomposite (Fe3O4/CS-biguanidine/Au NPs). The bioshells facilitate to protect the core ferrite NPs as well as provides stability to the synthesized Au NPs by capping. The material was characterized using different analytical techniques like Fourier Transformed Infra-Red spectroscopy (FT-IR), Inductively Coupled Plasma-Optical Emission Microscopy (ICP-OES), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-ray spectroscopy (EDX), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM) and X-ray Diffraction (XRD) studies. We explored the biological application of the nanocomposite in determining cytotoxicity of three adenocarcinoma cell lines (PC-14, LC-2/ad, HLC-1) through the MTT assay. The material showed very good activity by exhibiting very low % cell viability over the cell lines dose-dependently. The IC50 of Fe3O4/CS-biguanidine/Au NPs were observed 503, 398 and 475 µg/mL respectively against the three cell lines. The best output was observed at a concentration of 1000 µg/mL of catalyst in terms of cytotoxicity and inhibition of lung cancer growth. The anti-cancer potential was found in close relation to their antioxidant potential.  相似文献   

6.
以四水合氯化亚铁和硝酸银为原料,硼氢化钠为还原剂,氧化石墨烯(GO)为载体,通过原位还原法制备了具有磁分离功能的银/四氧化三铁/还原氧化石墨烯(Ag/Fe_3O_4/rGO)纳米复合抗菌材料.采用X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)、透射电子显微镜(TEM)等对复合材料进行了表征.结果显示,Fe_3O_4和Ag纳米颗粒均匀分布在rGO片层上.复合材料的饱和磁化率(Ms)为40.5 A·m~2·kg·(-1),表明其具有较强的磁性,将其与菌液混合后,在磁场作用下10 min即可吸附沉降完成磁分离.以大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)为实验菌株,通过琼脂扩散法评价了复合材料的抗菌性能.结果表明,该复合材料具有良好的抗菌效果,对E.coli和S.aureus的抑菌圈直径分别为18 mm和13 mm,最低抑菌浓度值(MIC)分别为50 mg/L和80 mg/L,最低杀菌浓度值(MBC)分别为30 mg/L和50 mg/L.  相似文献   

7.
Via a facile, one-pot solvothermal synthesis, highly uniform FePt/Fe3O4 core-shell nanoparticles are successfully developed, which further demonstrates their superiority in the MR imaging of living cells.  相似文献   

8.
The preparation of pyrazolo pyrimidinone derivatives was performed by using five component reactions of phthalaldehyde, cyanomethylamine, electron deficient acetylenic compounds, isocyanate, hydrazine, and catalytic amounts of ZnO/Fe3O4-magnetic nanoparticles as a high performance catalyst under ultrasonic conditions at ambient temperature in aquause media at room temperature. It should be mentioned that this catalyst was prepared using Spinacia oleracea water extract. In addition, for investigation of antioxidant ability, radical trapping by DPPH and reducing power of ferric ion experiments was performed. As a result, synthesized compounds show excellent radical trapping by DPPH and good reducing ability of ferric ion. The current procedure has the benefits for instance excellent yield of reaction, green media, and easy separation of product and catalyst.  相似文献   

9.
Regarding applicative, facile, green chemical research, a bio-inspired approach is being reported for the synthesis of Ag nanoparticles by pectin as a natural reducing and stabilizing agent without using any toxic and harmful reagent. The biosynthesized Pectin/Ag NPs were characterized by advanced physicochemical techniques like ultraviolet–visible (UV–Vis), Fourier Transformed Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), High-Resolution Transmission Electron Microscopy (HR-TEM), Energy Dispersive X-ray spectroscopy (EDX), and X-ray Diffraction (XRD) study. It has been established that pectin-stabilized silver nanoparticles have a spherical shape with a mean diameter from 15 to 20 nm. After that, the biological performance of those biomolecules functionalized Ag NPs was investigated. In the MTT assay, human colorectal carcinoma (HCT-8 [HRT-18], Ramos.2G6.4C10, HT-29, and HCT 116) and normal cell lines (HUVEC) were used to study the cytotoxicity and anticancer potential of human colorectal over the AgNO3 and Pectin/Ag NPs. The cell viability of Pectin/Ag NPs was very low against human colorectal carcinoma cell lines without any cytotoxicity on the normal (HUVEC) cell line. The best anti-human colorectal carcinoma properties of Pectin/Ag NPs against the above cell lines was in the case of the HCT 116 cell line. The antioxidant properties of the AgNO3 and Pectin/Ag NPs were calculated against DPPH free radicals. The IC50 of Pectin/Ag NPs was 167 µg/mL. According to the above results, the Pectin/Ag NPs may be administrated to treat human colorectal carcinoma in humans.  相似文献   

10.
Green chemistry-assisted biocompatible copper (Cu), silver (Ag), and iron oxide (Fe2O3) nanoparticles (NPs) synthesis along with surface modification using Koelreuteria apiculata is demonstrated in this research, for the first time. Appropriate analytical techniques were utilized to confirm the preparation, spherical morphology, and crystalline structure of each of the NPs. The antioxidant nature of synthesized NPs was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. Besides, the antimicrobial activity was also performed using bacterial strains of Staphylococcus aureus, Escherichia coli, and Salmonella typhi. Aspergillus sp. was designed as marker specie for the antifungal studies. The outcomes of NPs exposure, analyzed with reference to Chlorella sp. of the algal family exhibit the numerical values around 833% for AgNPs, 497% of CuNPs, and 456% for Fe2O3NPs. Phytotoxicity assay performed on the seeds of Vigna radiata and Cicer arietinum further validate the accordant nature of NPs towards vivacity. Allium cepa was also used as a test model to ascertain the genotoxic effects of the NPs wherein the mitotic index (MI) was calculated for AgNPs, CuNPs, and Fe2O3NPs as 42.1, 51.7, and 54.2% respectively. The outcomes of this research proved the suitability and affordability of our NPs developed using green synthesis for new industrial applications of in-situ reduction of carcinogenic compounds from water and soil.  相似文献   

11.
In this study, an eco-friendly and low-cost procedure for the synthesis of White tea plant extract modified magnetic nanocomposite (Fe3O4@W.tea) has been demonstrated. Ag nanoparticles (Ag NPs) were further decorated in situ over the designed Fe3O4@W.tea nanocomposite exploiting the plant derived phytochemicals as bio-reductant and stabilizer. The resulting Fe3O4@W.tea/Ag nanocomposite was characterized by various analytical methods like Fourier Transformed Infra Red (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), energy dispersive X-ray analysis (EDX) elemental mapping, transmission electron microscopy (TEM), vibrating-sample magnetometer (VSM), X-ray diffraction analysis (XRD), and inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. The as-synthesized bio-nanomaterial was used as an excellent heterogeneous and magnetically retrievable catalyst in the three-component condensation of 4-hydroxycoumarin, malononitrile and various aldehydes in refluxing aqueous media. A broad range of aromatic aldehydes underwent the reaction to produce diverse pyrano[3,2-c]chromene derivatives in very good yields irrespective of the nature of bearing functional groups or their respective geometrical positions. Due to superparamagnetic character, the material was easily magnetically decanted out and recycled for 8 successive times with preservation of its catalytic activity. After the chemical applications we also explored the material biologically in the resistance of human colon cancer and thereby studied the cytotoxicity over two standard cell lines, HT-29 and Caco-2. The conventional MTT assay was carried out over them which revealed an increase in % cell viability dose dependently. The IC50 values observed in the two cell lines were 384.2 μg/ml and 254.6 μg/ml respectively. In addition, DPPH radical scavenging test was performed for studying anti-oxidant activity. The results validate the administration of Fe3O4@W.tea/Agnanocomposite as a competent colon protective drug in the clinical trial studies over human.  相似文献   

12.
《Comptes Rendus Chimie》2014,17(9):927-933
Fe3O4 nanoparticles were prepared and modified with chloropropyl trimethoxysilane (Cl-PTMS). The N,N′-bis(3-salicylidenaminopropyl)amine (salpr) Schiff base ligand was then immobilized on modified Fe3O4, which was followed by the addition of VOSO4 in order to complex it with immobilized sa0lpr. The obtained nanocatalyst designated as VO(Salpr)/SCMNPs was characterized by FT–IR, XRD, SEM, TEM, and VSM techniques. It was found that VO(salpr)/SCMNPs successfully catalyze the epoxidation of allyl alcohols, such as limonene, 1-octene-3-ol, trans-2-hexene-1-ol and geraniol with 50 to 100% conversion and 62 to 100% selectivity with tert-butylhydroperoxide (TBHP). The study of this catalyst's stability and reusability revealed that VO(salpr)/SCMNPs behaves heterogeneously with no desorption during the course of the epoxidation reactions.  相似文献   

13.
The present work demonstrated an eco-friendly and facile method for the preparation of starch/Fe3O4/zeolite-bionanocomposite (BNC) at moderate temperature. Zeolite and starch were used as solid support and stabilizer, respectively. The analysis of UV–vis showed the appearance of surface plasmon resonance. From PXRD analysis, the incorporation of magnetite nanoparticles (NPs) in zeolite substrate results in reducing of intensities and broadening of the zeolite peaks of BNC. The TEM analysis showed the formation of highly distributed Fe3O4-NPs with an average diameter and standard deviation of 9.24 ± 3.57 nm. The FESEM and EDX analyses imply that Fe3O4-NPs were homogeneously formed on the surface of the zeolite substrate. VSM analysis illustrated the as prepared BNC possessed magnetic behaviour with a saturation magnetization and coercivity of 1.84 emu g−1 and 17.76 G, respectively. The prepared BNC showed potential applicability in energy as low-cost electrode material. The BNC was used as a non-precious catalyst for oxygen reduction reaction (ORR) in the alkaline medium. The presence of starch and zeolite promoted long term stability up to 1000 cycles and avoid the dissolution and agglomeration of iron oxide. The ORR commences at the onset potential of 0 V follows by the two successive reduction peaks at −0.48 V and −1.00 V.  相似文献   

14.
A novel magnetic nanocomposite of Au-Ag nanoparticles anchored on Fe3O4/graphene oxide spheres (Fe3O4/GO/Au-Ag) was successfully fabricated by the layer-by-layer assembly technique. The prepared Fe3O4/GO/Au-Ag was fully characterized by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), field-emission scanning electron microscopy (FE-SEM), energy-dispersive x-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Raman spectroscopy. This nanocomposite showed unique catalytic performance for the synthesis of Spiro[indoline-3,5′-pyrido[2,3-d:6,5-d’]dipyrimidine]-pentaone derivatives by the three-component condensation reaction of isatins, barbituric acids and 6-amino uracil at room temperature and in aqueous media. The significant advantages of this protocol include highly stable, easily separable and reusable catalyst, simple operation, environmental friendliness and excellent yields.  相似文献   

15.
In-situ synthesis of TbAlO3 (TAP)/Tb3Al5O12 (TAG)/Tb2O3 three-component nanocomposite by sol–gel method using natural reactants and investigation of its photocatalytic activity can be considered eco-friendly aspects of this work. The bioactive components of natural compounds may play as a reductant and progress the process through auto-combustion sol–gel technique. It was found that Mulberry has more bioactive components than Capparis spinosa L., so nucleation overtook growth and produced finer particles with less agglomeration. Optical property studies represented a band gap at about 3.8 eV that is different from the amounts related to TAP and TAG. Hence, e--h+ transfers in this nanocomposite were studied by estimation of energy levels of its constituents. According to findings, these components formed a UV-active photocatalyst with Type-I configuration to degrade organic pollutants. In other words, presence of Tb2O3 helped to benefit from properties of two ferroelectric compounds, that they have large band gaps, in photocatalytic reactions. After optimizing the photocatalytic parameters, maximum yield was obtained at about 94 %. Kinetics studies showed the photocatalytic process follows zero-order kinetics. In addition, the oOH was found as the most active promoter agent.  相似文献   

16.
Herein, we represent the bio-synthesis of silver nanoparticles (Ag NPs) employing Oak gum as the green template, an efficient natural and non-toxic reductant and stabilizer based on its phytochemicals by using ultrasonic irradiation. The characterization of as-synthesized Ag NPs was performed through Fourier transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), elemental mapping, UV–Vis and X-ray diffraction (XRD). After the characterization, the synthesized Ag NPs/O. Gum was engaged in biological assays like study of anti-oxidant properties by DPPH mediated free radical scavenging test using MeOH and BHT as reference molecules. Thereafter, on having a significant IC50 value in radical scavenging assay, we extended the bio-application of the desired nanocomposite in anticancer study of A549, Calu6 and H358 human lung cell lines in-vitro through MTT assay. They had very low cell viability and high anti-human lung cancer activities dose-dependently against the cell lines without any cytotoxicity on the normal cell line (MRC-5). The IC50 of Ag NPs/O. Gum was found 161.25, 289.26 and 235.29 µg/mL against A549, Calu6 and H358 cell lines, respectively. Maybe significant anti-human lung cancer potentials of Ag NPs/O. Gum against common lung cancer cell lines are related to their antioxidant activities. So, these results suggest that synthesized Ag NPs/O. Gum as a chemotherapeutic nanomaterial have a suitable anticancer activity against lung cell lines.  相似文献   

17.
采用简便的化学浸渍法制备了新型磁性可分离的纳米复合物H5PMo10V2O40/Fe3O4/g-C3N4(PMoV/Fe3O4/g-C3N4),并进行了详细的表征,采用电位滴定法测定了催化剂酸性.该PMoV/Fe3O4/g-C3N4纳米复合物在硫化物选择氧化为砜或亚砜的反应中表现出较高的催化活性;考察了在优化反应条件下,它在含硫(包括二苯并噻吩DBT)模拟油或真实石油的催化氧化反应中的催化性能;特别考察了各种含氮化合物,以及1-环和2-环芳香烃作为共溶剂对DBT脱硫效果的影响.采用外加磁场即可方便地将该催化剂从反应混合物中分离和回收.选取最好的萃取剂,通过简单的倾滤就可很容易地将剩余反应物从产物中分离出来.该纳米催化剂具有高催化活性,且容易重复使用,至少可以重复使用4次而未见催化活性明显下降.  相似文献   

18.
In the current study, a green and facile route for the synthesis of iron nanoparticles (FeNPs) was adopted. The FeNPs were fabricated via a single step green route using aqueous leaves extract of Plumeria obtusa (P. obtusa) as a capping/reducing and stabilizing agents. The FeNPs were characterized by UV/Vis (Ultraviolet/Visible), FTIR (Fourier Transform Infra-Red spectroscopy), TEM (Transmission Electron Microscopy), SEM (Scanning Electron Microscopy) and XRD (X-Ray Diffraction) techniques. The FeNPs were of spheroidal shape with average size of 50 nm. The biosynthesized FeNPs were further evaluated for their biological activities like antimicrobial, antioxidant and biocompatibility. The FeNPs displayed auspicious antimicrobial activity against bacterial (E. coli, B. subtilis) and fungal strains (A. niger) and S. commune. The test performed against red blood cells (RBCs) lysis (1.22 ± 0.02%) and macrophage (31 ± 0.09%) showed biocompatible nature of FeNPs. In vitro cytotoxicity against AU565 (82.03 ± 0.08–23.65 ± 0.065%) and HeLa (88.61 ± 0.06–33.34 ± 0.06%) cell lines showed cell viability loss in dose dependent manner (FeNPs 25–100 μg/mL). The antioxidant activities values were determined through DPPH, TRPA, NO and H2O2 assays with values 70.23 ± 0.02%, 76.65 ± 0.02 μg AAE/mg, 74.43 ± 0.04% and 67.34 ± 0.03%, respectively. Based on the bioactivities, the green synthesized FeNPs have potential for therapeutic applications.  相似文献   

19.
采用共沉淀法制备了Fe3O4磁性纳米粒子,将其负载于氨基吡啶修饰多壁碳纳米管(MWCNT-AP)上,得到具有良好的分散性和超顺磁性的Fe3O4/MWCNT-AP复合物.通过傅里叶变换红外(FT-IR)光谱、X射线衍射(XRD)和磁滞回线测量等方法对Fe3O4/MWCNT-AP复合物进行了表征.扫描电镜(TEM)结果表明:Fe3O4磁性纳米粒子多集中于碳纳米管MWCNT-AP的端部,形成的复合物在极性溶剂中具有良好的分散性和超顺磁性;辣根过氧化酶(HRP)可通过物理作用吸附于Fe3O4/MWCNT-AP复合物表面.酸性条件下(pH 4.0),Fe3O4/MWCNT-AP复合物使HRP的最大反应速率(Vmax)提高了3倍.  相似文献   

20.
采用共沉淀法, 以替加氟(Tegafur, TF)插层层状双金属氢氧化物(LDHs)纳米杂化物(TF-LDHs)包覆磁性基质Fe3O4, 得到了具有核/壳结构的纳米复合体[Fe3O4@(TF-LDHs)], 采用XRD, FTIR, TEM, VSM和元素分析等技术对样品的化学组成、 晶体结构\, 形貌及磁性等进行了表征, 探讨了药物分子在LDHs层间的存在状态, 考察了其药物释放行为. 结果表明, Fe3O4@(TF-LDHs)纳米复合体具有顺磁性, 其比饱和磁化强度随磁性基质含量的增大而增强; TF分子在LDHs层间以长轴略倾斜于LDHs层板的方式呈双层排布; Fe3O4@(TF-LDHs)纳米复合体具有明显的药物缓释性能, 其释放动力学过程符合准二级动力学方程, 颗粒内部扩散为释放过程的速率控制步骤.  相似文献   

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