B&M Carb-GCB (graphite-carbon black)/PSA (ethylene diamine – n-propyl) double SPE composite column has the same retention capacity as GCB/NH2, which is suitable for the purification of samples of pesticide residue detection. PSA has more a secondary amine than NH2, so the ion exchange capacity is larger and can be used as a complexation ligand for some metal ions, providing a different selectivity than GCB/NH2.

The equivalent of Waters Sep-Pak Carbon Black/PSA。