Surrogate Standard Stock Solution, 1.2ml, nonane

Monocrotophos, 10 µg/ml, Ethyl acetate, 10ml

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

Metformin, 1000μg/ml in MeOH, 1ml