Manuela Melucci replied: We used commercial graphene oxide powder (Abalonyx) and commercial hollow ber cartridges (Plasmart 25, Versatile PES Medica). The loading is performed by using a water suspension of GO and the xation is done in an oven (air, ambient pressure). Thus, the method is intrinsically scalable.The performance curves (removal vs. GO loading) were done by performing experiments in duplicate on two independent cartridges. All the deviation standards reported in the paper were calculated from two independent experiments. In general, the performance of the cartridges at lower loadings were highly reproducible while the results at 10% GO loading were affected by the lower water permeability of the membranes. We are currently using 1% inner coated bers and related lters for the removal of other contaminants from water with good reproducibility.