Fabrication of a nitric oxide gas sensor using microwires and basic research for its application

Abstract

Purpose: Although nitric oxide (NO) is considered one of the initial signals that promote postsurgery liver regeneration, NO's exact role in the liver regeneration mechanism is still not clear. Therefore, developing a practical gas sensor and testing it in a clinical setting through basic research will lay the groundwork for advanced clinical research on the action mechanism of NO. Methods: A thin nano wire NO sensor was made by wrapping a pair of parlyene-coated gold wires around a needle. The NO blood concentration determined by measuring the potential difference across the oscilloscope using electrical conductivity. In order to measure changes in NO level before and after the surgery, the NO sensor was inserted in the hepatic portal vein and a 75 percent partial hepatectomy was performed. The NO blood concentration was measured regularly with both the NO kit and the sensor. Results: One significant challenge was separation of the wire upon insertion into the hepatic portal vein. Despite separation, the constant measurements of the wire-type sensor were similar to those measured by the NO measurement kit. Conclusion:The development of a needle-type sensor allowed for easier insertion. In the future, using difference in electric potential, as used in the NO sensor, may be a more effective method of measuring blood ion concentration.