Journal of Theoretical and Applied Physics (JTAP) Inactivation by helium cold atmospheric pressure plasma for Escherichia coli and Staphylococcus aureus Volume 14 (2020) Issue 1, October 2019 2023 11 17 Inactivation by helium cold atmospheric pressure plasma for Escherichia coli and Staphylococcus aureus 10.1007/s40094-019-00362-4 EN Khaled Lotfy Department of Biology, Faculty of Science, Branch of Tayma, Tabuk University, Tabuk, Saudi Arabia King Marriott Higher Institute of Engineering & Technology, Alexandria, Egypt Sayed Mohammed Khalil Physics Department, Faculty of Science, Sohag University, Sohag, Egypt University College, Umm Al-Qura University, Alqunfadah, Saudi Arabia Hany Abd El-Raheem Center for Materials Science, Zewail City of Science and Technology, October Gardens, 6th of October City, Giza, Egypt Journal Article 2023 11 17 AbstractA helium cold atmospheric pressure plasma jet (HCAPPJ) driven by a commercial neon power supply was designed and utilized for inactivation bacteria. The generated reactive spices by HCAPPJ were investigated by optical emission spectroscopy. The reactive species of OH, OI, OI, N21+, N21+ and He were identified in the UV–Vis wavelength region. The reactive species was not detected between 200 nm and 300 nm, as the flow rate of helium gas increased that led to the plasma temperature reducing to a value near to the room temperature. In this work, we studied the impact of HCAPPJ on Gram-positive and Gram-negative bacteria. The survival amounts of the two types of bacteria were decreased vastly when the rate flow rate was equal to 10 L/min.