METHOD AND SENSOR FOR MEASURING CARBON DIOXIDE

摘要

PURPOSE:To obtain a carbon dioxide sensor which is so constructed that the deterioration of the life thereof by drying of microorganism bacteria is prevented and that the carbon dioxide past a gas permeable membrane is made hardly dissipatable by providing a buffer soln. reservoir or layer near the microorganism bacteria. CONSTITUTION:The sensor for measuring carbon dioxide has an oxygen electrode body 7, a cathode 5 consisting of platinum and an anode 6 consisting of lead and is provided with an electrolyte 8. The top end of the electrode 7 is coated with the gas permeable membrane 4 in such a manner that the part of the cathode 5 is fully coated. An immobilizing film 2 for the microorganisms 3 disposed to the outside of the membrane 4 is coated with a dialysis membrane 10 made of acetyl cellulose in the form of enclosing the entire part thereof. The immobilized microorganisms 2 and the membrane 10 are immersed into the buffer soln. 13 of a high pH value stored form a spacer 11. The sensor is so constituted that the buffer soln. 13 and the outside contact each other via a gas permeable membrane 12. The membrane 12 is fixed by rubber ring (may be an O-ring) 9. The microorganism bacteria are thus preserved without being dried.