Khaled Najieb Elshuraydeh, Professor Hanan Issa Malkawi, and Mona Hassuneh (2008) Method for the Production of Bare (Non-functionalized) Multiple element Magnetic Nanoparticles and their use in Fast Detection and Removal of Pathogenic Bacteria from Water Resources. Registered Patent # (2450), Ministry of Industry and Trade, Amman, Jordan.
|PDF - Accepted Version|
The invention provides a method where fly ash collected from chimneys of iron and steel factories, was used for the production of Multiple-element Magnetic Nanoparticles (MMN). Wet sieving of fly ash was performed and dried up in an oven. Magnetites in the dry product were separated through a magnetic field. This constituted 95% of the original product. The dried magnetic product was then well mixed with sodium chloride salt (NaCl) (ratio 1:10, respectively) in a ceramic pot and stirred thoroughly to provide for a good dispersion. The magnetites in the attached ash to the inner surface of the pot were harvested by applying a permanent magnet at the outer surface of the pot and attached dust was blown away by jet air using a small air pump. The magnet was removed and magnetites were collected in a test tube. This process was repeated several times until the required sample size of magnetites was produced. Characterization of the MMN in terms of sizes and chemical components were conducted using Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM) and Atomic Absorption. This invention relates also to the use of these multiple-element magnetic nanoparticles (MMN) as bare (non-functionalized) and without any surface modifications to detect, capture and remove bacterial pathogens from water suspension. The nanoparticles were attracted rapidly to the surface of the bacterial cells when mixed with bacterial suspension as viewed under the Transmission Electron Microscope (TEM). Some nanoparticles were able to penetrate inside the bacterial cells as revealed by thin sectioning imaging method and viewed under TEM. The attached bacterial-nanoparticles aggregate complexes were removed from water suspension by applying a magnet to the wall side of the tubes. The original bacterial counts, colony forming units (CFU/ml), were determined in the original suspension and were found to be (2 x 105 CFU/ml), while in the supernatant layer when applying the magnet (101-102 CFU/ml). The bacterial counts were reduced by 103 CFU/ml. The MMN was also applied to naturally contaminate environmental water samples; wastewater and grey water. The coliform bacterial counts (such as E. coli and Salmonella: often used as indicator of fecal pollution of water) were determined before and after applying the magnet. It was found that when plating on coliform bacterial selective media, the CFU/ml was reduced by a factor of 102-103 for grey water and a factor of 103-104 for wastewater. The effect of MMN on bacterial growth inhibition was tested and found to have no effect on bacterial growth and viability. Very low amount of MMN (4.5 mg/mL) was used for all the above applications.
|Subjects:||Technology > Nanotechnology and environmental applications|
Physical Science > Nanomagnetics
Biomedical Science > Nanotechnology for human health
|Deposited By:||Lesley Tobin|
|Deposited On:||14 Aug 2009 10:12|
|Last Modified:||17 Aug 2009 09:44|
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