Substances: 5-Fluorouracil (GHASVSINZRGABV-UHFFFAOYSA-N) 5-Methyl-Benzotriazole (LRUDIIUSNGCQKF-UHFFFAOYSA-N) 4-Formylaminoantipyrin (4-FAA) (WSJBSKRPKADYRQ-UHFFFAOYSA-N) Keywords: monitoring