Magnetically propelled, encapsulated XAD-2 and microphase extraction technique for a rapid quantitation of basic drugs in serum by GC

A novel, simple, and highly economical technique is described for a rapid gas chromatographic screening and quantitation of basic drugs in serum. The drugs are adsorbed directly form 1 ml of serum onto 400 mg of XAD-2 resin, encapsulated within a rigid, porous, spherical polypropylene capsule, 2 cm in diameter. The capsule also contains a ferromagnetic bar that provides controlled agitation of contents under the influence of a rotating magnet. Resolution and quantitation of samples spiked with 18 basic drugs are provided by a nitrogen detector. The yields are quantitatively linear in both sub-therapeutic and toxic ranges for most drugs; the extracts exhibit minimal background in the range of sensitivities indicated; total extraction time is 20 min.