Hexavalent Chromium (Cr+6), 10mg/mL in H2O, 500ml

Metoprolol (free base), 1000µg/mL, Solvent-methanol, Unit 1mL, # of units-1, Cas.no. 51384-51-1

13C3-Caffeine, 10mg

ι-1,2,5,6,9,10-Hexabromocyclododecane, 1.2ml x 50ug/ml, toluene