Efficient endoscope inner channel surface disinfection using a two-step atmospheric pressure plasma treatment

•Plasma activated water with varying chemistry can be produced via changes in operating powers.•Cold atmospheric pressure plasma causes significant reduction in single- and mixed- species biofilms.•Plasma activated water effectively acts as an antimicrobial agent.•Combined plasma treatments are highly effective at removing biofilm contamination.•Plasma treatments used do not cause damage or functionalisation to endoscopic test pieces.