抄録
We designed the metal coating hollow fiber membrane coated with metal on the outer surface of the capillary membrane. We found that bacteria on the membrane were sterilized by a direct electric current passed through the metal on the membrane surface. The sterilization mechanism was created as follows: The leakage of intracellular contents was confirmed when bacteria were sterilized by the electric current. This leakage proved indirectly that the cell membrane was partially broken. In this paper, the leakage phenomenon and the mechanism on the sterilization were focused, and the possibility of whether the metal coating hollow fiber membrane became a new gene extraction device was examined. After the direct current to the membrane-surface-trapped Escherichia coli O157 was passed, the gene was examined. As a result, the vero toxin type 1 gene could be detected. The detection sensitivity on the gene extraction mainly depended on the concentration of sodium dodecyl sulfate (SDS), which was an anion surfactant, and on the value of the direct electric current. The highest sensitivity in the extraction was obtained under 5% SDS and 300mA. Under these conditions, the vero toxin type 1 genes were obtained when the bacterial number in a physiological salt solution was more than 105CFU/ml. This system needed time to extract the gene in only 10 minutes. The system used also simpler equipment because it consisted of the perista pump and the power supply in addition to the membrane. Therefore the gene extraction method that used the metal coating hollow fiber membrane has the advantages of (a) requiring less time than a chemical extraction, which needs about an hour; (b) low contamination because of a simpler extraction process; and (c) the possibility of automation of the simple system.
