Naproxen, 100 µg/ml, Methanol, 1ml

Mono-ethyl phthalate (ring-1,2-13C2,99%, dicarboxyl-13C2,99%) 100 µg/mL in MTBE

Calycosin-7-O-beta-D-glucoside, >98%, 20mg

4,4’-Thiodianiline