Technological advances in the past 30 years have boosted the use of PSM （membrane separation processes）, important for its efficiency and flexibility of operation. These processes can be used in many types of separa...Technological advances in the past 30 years have boosted the use of PSM （membrane separation processes）, important for its efficiency and flexibility of operation. These processes can be used in many types of separation, with some advantages over the usual separation processes. NF （nanofiltration） is a membrane separation technique, which has properties intermediate between reverse osmosis and ultrafiltration in terms of separated species, because the average of the pores is in the range of 1/2 to 10 nm, and the separation occurs in function of load and size of the species. Usually removes species in solution with an effective diameter of about 1 nm or larger and multivalent ions to a greater extent than monovalent ions. The objective was to study the formation of biofouling on the surface of commercial nanofiltration membrane （Osmonics/GE） and surface membrane synthesized in our laboratory. The study was conducted in permeation system with filtration cell with tangential displacement of 15 bar for 8 days flow. DBNPA （2,2-dibromo-3-nitrilopropionamide） was used as a biocide agent, and an anti-fouling, in concentrations of 5 and 300 ppm, respectively, added to the water coming from the Beach Sea Galleon, RJ. The results demonstrated that there was no change in the flow and rejection of sulphate ions, even in the presence of anti-fouling. The count of aerobic, anaerobic and BRS （sulfate reducing bacteria） in seawater before and after using the DBNPA showed efficiency in controlling these groups of microorganisms and biofouling microbial consortium consisting of the existing in seawater.展开更多
Bacterial infections may lead to diverse acute or chronic diseases （e.g., inflammation, sepsis and cancer）. New antibiotics against bacteria are rarely discovered in recent years, which necessitates the exploration ...Bacterial infections may lead to diverse acute or chronic diseases （e.g., inflammation, sepsis and cancer）. New antibiotics against bacteria are rarely discovered in recent years, which necessitates the exploration of new antibacterial agents. Engineered nanomatetials {ENMs） have been extensively studied for antibacterial use because of their long lasting killing effects in wide spectra of bacteria. Graphene oxide （GO） is one of the most widely studied ENMs and exhibit strong bactericidal effects. The physicochemical properties of GO play important roles in bacterial killing by triggering a cascade of toxic events. Many studies have explored the signaling pathways of GO in bacteria. Although molecular initiating events （MIEs） of GO in bacteria dominate its killing efficiency as well as toxicity mechanisms, they have been rarely reviewed. In this report, we discussed the structure-activity relationships （SARs） involved in GOinduced bacterial killing and the MIEs including redox reaction with biomolecules, mechanical destruction of membranes and catalysis of extracellular metabolites. Furthermore, we summarized the clinical or commercial applications of GO-based antibacterial products and discussed their biosafety in mammal. Finally, we reviewed the remaining challenges in GO for antibacterial applications, which may offer new insights for the development of nano antibacterial studies.展开更多
文摘Technological advances in the past 30 years have boosted the use of PSM （membrane separation processes）, important for its efficiency and flexibility of operation. These processes can be used in many types of separation, with some advantages over the usual separation processes. NF （nanofiltration） is a membrane separation technique, which has properties intermediate between reverse osmosis and ultrafiltration in terms of separated species, because the average of the pores is in the range of 1/2 to 10 nm, and the separation occurs in function of load and size of the species. Usually removes species in solution with an effective diameter of about 1 nm or larger and multivalent ions to a greater extent than monovalent ions. The objective was to study the formation of biofouling on the surface of commercial nanofiltration membrane （Osmonics/GE） and surface membrane synthesized in our laboratory. The study was conducted in permeation system with filtration cell with tangential displacement of 15 bar for 8 days flow. DBNPA （2,2-dibromo-3-nitrilopropionamide） was used as a biocide agent, and an anti-fouling, in concentrations of 5 and 300 ppm, respectively, added to the water coming from the Beach Sea Galleon, RJ. The results demonstrated that there was no change in the flow and rejection of sulphate ions, even in the presence of anti-fouling. The count of aerobic, anaerobic and BRS （sulfate reducing bacteria） in seawater before and after using the DBNPA showed efficiency in controlling these groups of microorganisms and biofouling microbial consortium consisting of the existing in seawater.
基金supported by the National Natural Science Foundation of China (31671032)Key Project of Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (17KJA310003)+2 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)supported by the Recruitment Program of Global Youth Experts of ChinaStrategic Project for Developing Outstanding Institutes in Suzhou (MCMX201604)
文摘Bacterial infections may lead to diverse acute or chronic diseases （e.g., inflammation, sepsis and cancer）. New antibiotics against bacteria are rarely discovered in recent years, which necessitates the exploration of new antibacterial agents. Engineered nanomatetials {ENMs） have been extensively studied for antibacterial use because of their long lasting killing effects in wide spectra of bacteria. Graphene oxide （GO） is one of the most widely studied ENMs and exhibit strong bactericidal effects. The physicochemical properties of GO play important roles in bacterial killing by triggering a cascade of toxic events. Many studies have explored the signaling pathways of GO in bacteria. Although molecular initiating events （MIEs） of GO in bacteria dominate its killing efficiency as well as toxicity mechanisms, they have been rarely reviewed. In this report, we discussed the structure-activity relationships （SARs） involved in GOinduced bacterial killing and the MIEs including redox reaction with biomolecules, mechanical destruction of membranes and catalysis of extracellular metabolites. Furthermore, we summarized the clinical or commercial applications of GO-based antibacterial products and discussed their biosafety in mammal. Finally, we reviewed the remaining challenges in GO for antibacterial applications, which may offer new insights for the development of nano antibacterial studies.
