Substances: 4-Hydroxy Diclofenac (KGVXVPRLBMWZLG-UHFFFAOYSA-N) 1-Methyl-Benzotriazole (HXQHRUJXQJEGER-UHFFFAOYSA-N) 5-Hydroxy Diclofenac (VNQURRWYKFZKJZ-UHFFFAOYSA-N) Keywords: monitoring