[13C22 15N2]-Tetracycline

Sodium 1H,1H,2H,2H-perfluoro-1-[1,2-13C2]-octane sulfonate (6:2), 50µg/ml in MeOH, 1,2ml

2,3,3',4,5,5'-Hexachlorobiphenyl-2',4',6'-d3,100 µg/mL,isooctane,1mL

3,5,6-trichloro-2-pyridinol(4,5,6-13C3, 99%) cp 97%, 100µg/ml in Acetonitrile, 1,2ml