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Trace volatile constituents of human urine, serum, and cerebrospinal fluid were concentrated on a porous polymer precolumn, and resolved with high-efficiency glass capillary columns. Thin-film glass columns facilitate effective resolution of underivatized compounds within the volatility range up to docosane in relatively short analysis times. Glass capillary columns coated with stationary phases of different polarity were used. Recorded volatile metabolic profiles of human urine are altered after the sample is treated with β-glucuronidase and sulphatase.

A method for multicomponent determination of steroids In small plasma samples is described. Complex mixtures of plasma steroids are resolved by means of glass capillary gas chromatography as methoxlme-trimethylsllyl derivatives. Fractionation of plasma steroids into different conjugate types Is employed prior to gas-chromatographic determination. An effective column preconcentration procedure combined with high resolving power of glass capillary columns allows hlgh-sensitivity recording of steroid profiles with the flame ionization detector. In addition, a nitrogensensitive (thermionic) detector Is conveniently used for both selective detection of ketonlc steroids within the complex profiles and for selected hlgh-sensitivity measurements. Profiles of three different conjugate fractions can be obtained from 1-5 ml plasma samples in addition to the Isolated determination of plasma testosterone by electron capture detection.