EPA Method 551.1 Performance Check Soln

(±)-Verapamil-d3 hydrochloride (N-methyl-d3) ,1000 µg base/mL,MeOH,1mL

Diphenylacetic acid, 1000mg

2,2',3,4,5,6,6'-Heptachlorobiphenyl ,100 µg/mL,isooctane,1mL,