Toxic gas emissions are a critical global health concern, responsible for numerous deaths each year. These hazardous gases can cause severe physiological reactions and even death upon exposure. To address this issue, we propose a graphene-Kaptonbased flexible biosensor for non-invasive toxic gas detection. The sensor is designed to accurately detect and identify several harmful gases, including carbon monoxide (CO), fluorine azide ( FN3), hydrogen iodide (HI), nitrogen ( N2), methane ( CH4), nitrous oxide ( N2O), and ozone ( O3). Utilizing the Computer Simulation Technology (CST) Studio Suite 2024, we simulate the detection process, focusing on advanced techniques and miniature flexible structures. The sensor’s active element is a graphene patch embedded within a polyimide (Kapton) film, which allows for precise determination of the RF planar resonant structure’s frequency response. The graphene–Kapton biosensor is shown to have remarkable detection performance, as demonstrated by the results of the simulation, with a diffusivity of 9.09e−08[m2∕S] , an accuracy of 6.62e−13 , and a power loss of 1.5mW . These findings highlight the sensor’s potential as an effective tool for detecting and identifying toxic gases with high precision and efficiency.

The detection of toxic gases (CO, FN3, HI, N2, CH4, N2O, and O3) using a wearable Kapton–graphene biosensor for environmental and biomedical applications
    Abstract
        Graphical abstract
    1 Introduction
    2 Materials and methods
        2.1 Sensor design and structure
        2.2 Gas detection mechanisms
        2.3 Mathematical analysis
    3 Result and discussion
    4 Conclusion
    Acknowledgements 
    References

• Marzieh Ramezani Farani(Department of Biological Sciences and Bioengineering, NanoBio High-Tech Materials Research Center, Inha University, 100 Inha‑ro, Incheon 22212, Republic of Korea) Corresponding author
• Hanseung Kim(Department of Biological Sciences and Bioengineering, NanoBio High-Tech Materials Research Center, Inha University, 100 Inha‑ro, Incheon 22212, Republic of Korea)
• Munirah Alhammadi(Department of Biological Sciences and Bioengineering, NanoBio High-Tech Materials Research Center, Inha University, 100 Inha‑ro, Incheon 22212, Republic of Korea)
• Yun Suk Huh(Department of Biological Sciences and Bioengineering, NanoBio High-Tech Materials Research Center, Inha University, 100 Inha‑ro, Incheon 22212, Republic of Korea)