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Zhan S.,Nankai University | Zhu D.,Nankai University | Ma S.,Nankai University | Yu W.,Nankai University | And 4 more authors.
ACS Applied Materials and Interfaces

Magnetic Fe3O4/graphene composite (abbreviated as G-Fe3O4) was synthesized successfully by solvothermal method to effectively remove both bacteriophage and bacteria in water, which was tested by HRTEM, XRD, BET, XPS, FTIR, CV, magnetic property and zeta-potential measurements. Based on the result of HRTEM, the single-sheet structure of graphene oxide and the monodisperse Fe3O4 nanoparticles on the surface of graphene can be observed obviously. The G-Fe3O4 composite were attractive for removing a wide range of pathogens including not only bacteriophage ms2, but also various bacteria such as S. aureus, E. coli, Salmonella, E. Faecium, E. faecalis, and Shigella. The removal efficiency of E. coli for G-Fe3O4 composite can achieve 93.09%, whereas it is only 54.97% with pure Fe3O4 nanoparticles. Moreover, a detailed verification test of real water samples was conducted and the removal efficiency of bacteria in real water samples with G-Fe3O4 composite can also reach 94.8%. © 2015 American Chemical Society. Source

Zhan S.,Nankai University | Zhan S.,University of Notre Dame | Yang Y.,Nankai University | Shen Z.,Institute of Health and Environmental Medicine | And 5 more authors.
Journal of Hazardous Materials

A novel amine-functionalized magnetic Fe3O4-SiO2-NH2 nanoparticle was prepared by layer-by-layer method and used for rapid removal of both pathogenic bacteria and viruses from water. The nanoparticles were characterized by TEM, EDS, XRD, XPS, FT-IR, BET surface analysis, magnetic property tests and zeta-potential measurements, respectively, which demonstrated its well-defined core-shell structures and strong magnetic responsivity. Pathogenic bacteria and viruses are often needed to be removed conveniently because of a lot of co-existing conditions. The amine-modified nanoparticles we prepared were attractive for capturing a wide range of pathogens including not only bacteriophage f2 and virus (Poliovirus-1), but also various bacteria such as S. aureus, E. coli O157:H7, P. aeruginosa, Salmonella, and B. subtilis. Using as-prepared amine-functionalized MNPs as absorbent, the nonspecific removal efficiency of E. coli O157:H7 or virus was more than 97.39%, while it is only 29.8% with Fe3O4-SiO2 particles. From joint removal test of bacteria and virus, there are over 95.03% harmful E. coli O157:H7 that can be removed from mixed solution with polyclonal anti-E. coli O157:H7 antibody modified nanoparticles. Moreover, the synergy effective mechanism has also been suggested. © 2014 Elsevier B.V. Source

Guo C.,Huazhong Agricultural University | Zhou C.,Huazhong Agricultural University | Sai N.,Tianjin University | Ning B.,Institute of Health and Environmental Medicine | And 4 more authors.
Sensors and Actuators, B: Chemical

A new opal photonic crystal sensor (OPCS) that allows the detection of label-free bisphenol A (BPA) is proposed in the current study. The concept of developing photonic-based sensors using combined photonic crystal technology and molecular imprinting techniques is introduced. First batches of the BPA-imprinted monodisperse PMMA spheres with a diameter of 220 (±5) nm were prepared based on the suspension polymerization, so numerous nanocavities derived from BPA imprinting were distributed in the PMMA spheres. The liquid monodisperse microspheres were made into a polymerized crystalline colloidal array (PCCA) opal photonic crystal sensor. The inherent high affinity of the nanocavities distributed in the sphere allows OPCS to recognize BPA specifically. The sensor is characterized by a 3D-ordered interconnected lattice structure. Between the monospheres, there are well-arranged pores allowing the target molecules to embed and transport. As a result, changes in diffraction intensity which are related to BPA concentrations can be observed with the sensor. The detection ranges of OPCS are at 1 ng/ml-1 μg/ml level. The new sensory system has high selectivity of the target molecules in their natural forms, is easy to use, and costs low. Overall, the proposed approach provides a versatile analytical system for the establishment of a new sensor for the detection of endocrine-disrupting chemicals. © 2011 Elsevier B.V. All rights reserved. Source

Hong X.,Tianjin University | Peng Y.,Institute of Health and Environmental Medicine | Bai J.,Institute of Health and Environmental Medicine | Ning B.,Institute of Health and Environmental Medicine | And 3 more authors.

A novel opal closest-packing (OCP) photonic crystal (PC) is successfully prepared for naked-eye glucose detection. This PC is fabricated via a vertical convective self-assembly method with a new type of monodisperse microsphere polymerized by co-monomers, namely, methyl methacrylate (MMA), N-isopropylacrylamide (NIPA), and 3-acrylamidophenylboronic acid (AAPBA). The OCP PC has high stability and periodically-ordered structure, showing the desired structural color. The proposed PC material displays a red shift and reduced reflection intensity when detecting glucose molecules. The red-shift wavelength reaches 75 nm, which clearly changes the structural color from brilliant blue to emerald green. This visually distinguishable color change facilitates the detection of the glucose concentrations from 3 to 20 mm, which demonstrates the potential of the opal PC material for naked-eye detection. Thus, the novel PMMA-NIPA-AAPBA OCP PC is a simply prepared and sensitive material, which shows promising use in the diagnosis of diabetes mellitus and in real-time monitoring of diabetes. Different types of appropriated recognition groups are expected to be introduced into the 3D OCP PC to form new functional materials or chemical sensors, which will extensively broaden the PC material application. A novel opal closest-packing (OCP) photonic crystal (PC) is fabricated by self-assembly with a new type of microsphere polymerized by co-monomers. When glucose is added, this PC displays a red-shift, reduced intensity and a structural color change, which are caused by the swelling of the PC structure. These characteristics demonstrate that the proposed PC can be used in naked eye detection. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Zhang W.,Institute of Health and Environmental Medicine | Lei T.,Institute of Health and Environmental Medicine | Lin Z.-Q.,Institute of Health and Environmental Medicine | Zhang H.-S.,Institute of Health and Environmental Medicine | And 4 more authors.
Atmospheric Environment

Objection: To study the pollution of atmospheric particles at winter in Beijing and compare the lung toxicity which induced by particle samples from different sampling sites. Method: We collected samples from two sampling points during the winter for toxicity testing and chemical analysis. Wistar rats were administered with particles by intratracheal instillation. After exposure, biochemically index, esimmunity indexes, histopathology and DNA damage were detected in rat pulmonary cells. Result: The elements with enrichment factors (EF) larger than 10 were As, Cd, Cu, Zn, S and Pb in the four experiment groups. The priority control of the total concentration of polycyclic aromatic hydrocarbons (PAHs) in PM10 and PM2.5 of Near-traffic source was much higher than that of Far-traffic source, it demonstrated that near the traffic source of PAHs pollution was heavier than that of Far-traffic source, as it was close to main roads Beiyuan Road, motor vehicle emissions were much higher. The pathology of lung showed that the degree of inflammation was increased with the particle diameter minished, it was the same as the detection of biochemical parameters such as lactate dehydrogenase (LDH), Total antioxidant status(T-AOC) and total protein (TP) in BALF and inflammation cytokine(interleukin-1, interleukin-6 and tumor necrosis factor-alpha) in lung homogenate. The indexes of DNA damage including the content of DNA and Olive empennage of PM2.5 were significant higher than that of PM10 at the same surveillance point (P < 0.05), near-traffic particles were higher than the far-traffic particles at the same diameter, (P < 0.05). Conclusion: Near-traffic area particles had certain pollution at winter in Beijing. Meanwhile, atmospheric particulate matters on lung toxicity were related to the particles size and distance related sites which were exposed: smaller size, more toxicity; nearer from traffic, more toxicity. © 2010 Elsevier Ltd. Source

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