Keywords: high resolution mass spectrometry Substances: 5-Fluoro Cytosine (XRECTZIEBJDKEO-UHFFFAOYSA-N) 2-4-D (OVSKIKFHRZPJSS-UHFFFAOYSA-N) 3-5-Diiodo-L-tyrosine (NYPYHUZRZVSYKL-ZETCQYMHSA-N) 5-Hydroxy Diclofenac (VNQURRWYKFZKJZ-UHFFFAOYSA-N)