Direct serum injection in micellar liquid chromatography. Recovery of serum proteins and assay of hydrophilic drugs

The recovery of serum proteins from reversed-phase and internal-surface reversed-phase (ISRP) silica supports following direct serum injection was investigated using an eluent containing a micellar solution of sodium dodecyl sulphate (SDS). The results indicated that the recoveries of serum proteins were 98-103% for both supports. On the basis of the above findings, the separation and recovery of hydrophilic drugs (cephalosporins and salicylic acid) from human serum were investigated using acidic eluents including micellar solutions of SDS. They were completely separated from the components of serum, and the recoveries were 94-98% despite protein binding. Although the recommended eluent pH range is 6.0-7.5 for the ISRP support, eluents of pH 2-8 can be used with the micellar chromatographic system.