Real-Time Detection of Nitric Oxide Release in Live Cells Utilizing Fluorinated Xerogel-Derived Nitric Oxide Sensor

Abstract

Nitric oxide (NO) is an important signaling molecule that regulates a diverse range of physiological and cellular processes in many tissues. Therefore, the accurate de‐ tection of physiological NO concentration is crucial to the understanding of NO sig‐ naling and its biological role. There has been growing interest in the development of electrochemical sensors for direct and real-time monitoring of NO. As the direct electrooxidation of NO requires a relatively high working potential, further surface modification with permselective membranes is required to achieve the desired se‐ lectivity for NO via size exclusion or electrostatic repulsion. Here we reported a pla‐ nar-type NO sensor with a fluorinated xerogel-derived gas permeable membrane for real-time detection of NO release in live cells. First, we evaluated the biocompat‐ ibility of xerogel-derived NO permeable membranes modified with fluorinated functional groups by growing RAW 264.7 macrophages on them. And we per‐ formed the AFM measurements to examine the morphology of RAW 264.7 macro‐ phages on xerogel membrane. Finally, we successfully detected NO release in RAW 264.7 macrophages, using a planar-type xerogel-derived NO sensor. As a result, flu‐ orinated xerogel-derived membrane could be utilized as both NO permeable and cell-adhesive membranes. Besides, planar-type xerogel-based NO sensors can be easily applied to the cellular sensing system, with a simple coating procedure.