  Chemotherapy treatment usually involves the delivery of fluorouracil (5-Fu)
together with other drugs through central venous catheters. Catheters and their
connectors are increasingly coated (or impregnated) with silver or argentic
alloys/compounds. Complications such as broken catheters are common, leading to
additional suffering for patients and increased medical costs. Here, we uncover
a likely cause of such failure through a study of the surface chemistry
relevant to chemotherapy drug delivery, i.e. between 5-Fu and silver. We show
that silver catalytically decomposes 5-Fu, releasing HF as a product. This
reaction compromises the efficacy of the treatment, and at the same time,
releases HF which is damaging to both patient and catheter. Our study not only
reveals an important reaction which has so far been overlooked, but
additionally allows us to propose that graphene coatings inhibit such a
reaction and offer superior performance for cancer treatment applications.
