Screening biological samples for underivatized drugs using a splitless injection technique on fused silica capillary column gas chromatography.

A rapid screening technique is presented for the detection of underivatized drugs using a multi-level temperature program. This allowed for the identification of major clinically significant drugs extracted from serum, urine, and other body fluids. Acidic or basic extractions are injected into a gas chromatograph equipped with a flame ionization detector and a single wide-bore, thick film capillary using the splitless mode of injection. Identification is by retention time relative to that of a common internal standard. Deactivation of the fused silica liner is necessary to consistently detect low concentrations of specific drugs.