Nitrous Oxide Sensing using Oxygen-Insensitive Direct-Electron-Transfer-Type Nitrous Oxide Reductase

作者：Tsugawa Wakako^*; Shimizu Hitomi; Tatara Masahiro; Ueno Yoshiyuki; Kojima Katsuhiro; Sode Koji

来源：Electrochemistry, 2012, 80(5): 371-374.

DOI：10.5796/electrochemistry.80.371

• Nitrous Oxide
• Nitrous Oxide Reductase
• Direct Electron Transfer
• Cytochrome c

Nitrous oxide (N2O) is known as a greenhouse gas and a dominant ozone-depleting substance. It is is released mainly from agricultural processes. Therefore, the development of an on-site monitoring system is required to measure N2O concentration and control the release from the source. Using oxygen-insensitive cytochrome c-type nitrous oxide reductase, wNosZ, from Wolinella succinogenes, we have developed an electrochemical enzyme sensor. The sensor signal depends on the concentration of N2O in a reaction cell containing methoxy-5-methylphenazinium methylsulfate (mPMS) as an electron mediator under Ar atmosphere and, surprisingly, under air. Moreover, in the absence of addition of an electron mediator to the reaction cell, we observe that the reduction current depends on the concentration of N2O, which implies direct electron transfer. The wNosZ electrode is stable when stored at 4 degrees C for 2 weeks and is specific to N2O. These results suggest that wNosZ holds great promise as a component of a novel direct-electron-transfer-type electrochemical sensing system for N2O.

• 出版日期2012-5