LC/MS Analysis of Barbital in BSA (ODP2 HP)

Biological sample was analyzed directly using ODP2 HP. ODP2 HP is a polymer based reversed phase column. One advantage of ODP2 HP is the very low adsorption of proteins, because the surface of the packing material has a high polarity and the pore size is small. Since proteins like BSA are eluted early and its peak shape is sharp. ODP2 HP can separate drugs from proteins. Four LC/MS chromatograms of barbital were shown. These are comparison of using ODP2 HP and ODS, and barbital without BSA and with BSA. In using ODS (right), the peak height of barbital with BSA were lower than without BSA. It means there was ion suppression by existence of BSA. The comparison data of recovery of barbital also showed influence of BSA to ODS. ODP2 HP can be used for analysis of low molecular compounds in biological sample without bad influence of protein.



Sample : Barbital (500ppb) in BSA (7.0mg/L)
1. Barbital

Column       : Shodex ODP2 HP-2B, ODS from other manufacturer(2.0mmID*50mm esch)
Eluent       : 10mM Ammonium acetate/CH3CN=70/30
Flow rate    : 0.2mL/min
Detector     : ESI-MS (SIM negatie)
Column temp. : 30°C