Anti-bacterial activity of graphene is a well-researched and controversial topic where contradictory results have been published by various researchers.1,2 These contradictions are because of various parameters like concentration, exposure time, thickness, GO flake size, are among a few to mention.3 Assuming that graphene is anti-bacterial, several mechanisms like physical cell membrane damage, ROS generation, wrapping of bacteria by GO flakes and membrane stress were put forward.3 Our studies are directed towards studying the anti-bacterial activity of different graphene derivatives on different substrates and has been realized that the roughness of the substrate plays a determinant role in deciding the mode of anti-bacterial effect. Both bactericidal and bacteriostatic mechanisms were observed on rough surfaces and soft substrates respectively. We would like to conclude that graphene/graphene derivatives themselves act as both bactericidal and bacteriostatic, depending on the form they are used, irrespective of the substrate they are present on (conductor, semi-conductor or insulator).

Anti-bacterial activity of graphene is a well-researched and controversial topic where contradictory results have been published by various researchers.1,2 These contradictions are because of various parameters like concentration, exposure time, thickness, GO flake size, are among a few to mention.3 Assuming that graphene is anti-bacterial, several mechanisms like physical cell membrane damage, ROS generation, wrapping of bacteria by GO flakes and membrane stress were put forward.3 Our studies are directed towards studying the anti-bacterial activity of different graphene derivatives on different substrates and has been realized that the roughness of the substrate plays a determinant role in deciding the mode of anti-bacterial effect. Both bactericidal and bacteriostatic mechanisms were observed on rough surfaces and soft substrates respectively. We would like to conclude that graphene/graphene derivatives themselves act as both bactericidal and bacteriostatic, depending on the form they are used, irrespective of the substrate they are present on (conductor, semi-conductor or insulator).