A method for manufacturing plasma-activated saline for treatment of cancer cells. The method comprises the steps of immersing a cathode in saline solution in a container, positioning an anode at a fixed distance from a surface of said saline solution in said container and applying electrical energy to said anode for a fixed period of time, wherein said fixed distance and said fixed period of time are selected to cause a plasma self-organized pattern at a surface of said saline solution with an atmospheric discharge between said anode and said cathode.