Insecticidal effect of graphene as surface treatment for the control of two major stored product insects

Graphene, a recently discovered material with a unique two-dimensional (2D) structure, has shown insecticidal properties similar to inert dust protectants. However, its effectiveness as a surface treatment in food storage and processing facilities remains largely unexplored. In this study, we evaluated graphene powders applied at two doses (0.5 and 1 g/m2) on three different surfaces-metallic, concrete, and ceramic-against adults of the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), and the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). After 7 days of exposure, O. surinamensis exhibited 100 % mortality across all surfaces and both graphene doses, while T. castaneum required 14 days to reach 100 % mortality under the same conditions. Statistical analyses confirmed that surface type did not significantly influence graphene's insecticidal activity beyond the first day of exposure. The results suggest that graphene can be effectively used as a surface treatment for controlling stored-product insects, providing rapid and consistent mortality.