| 摘要 |
PURPOSE:To selectively sense the ethanol in a soln. and to measure the concn. thereof by providing the cell membrane fraction of acetic acid bacteria as an immobilized film on an O2 electrode. CONSTITUTION:The sensor formed by mounting the immobilized film 2 of the cell membrane fraction of the acetic acid bacteria to the O2 electrode 1, enclosing the same further with a gas permeable membrane 3 and fixing the same with an O-ring is connected to a recorder 4. The electrode 1 is then inserted into a thermostatic vessel 5 and the inside of the vessel 5 is filled with water, etc. The water is stirred by a magnetic stirrer 6, etc. The output of the electrode 1 stabilizes as well when the dissolved oxygen of the liquid in the vessel 5 attains a specified state. The output current value of the electrode 1 in this stage is measured. The output current decreases when an ethanol soln. of a known concn. is added to the vessel 5. The current value when the output current attains the specified state is measured and the current decrease value is measured. The calibration curve indicating the relation between the ethanol concn. and the current decrease value is formed by repeating the similar operation. The current decrease value is thereafter determined by using a sample soln. of a known concn. and the concn. corresponding to the value obtd. is read from the previously formed calibration curve. The concn. of the sample liquid is thus known. |
