A method for detecting trace quantities of organic drug material in a living animal under observation wherein samples of gaseous material effusing from the animal either by way of breath, through the skin or from a blood stream are passed through a three-stage membrane gas separator to enrich the concentration of the organic drug material in the gaseous sample. The enriched sample gas output of the membrane separator is fed to a gas analyzer such as a mass spectrometer for detecting the organic drug material, if any, in the sample gas under analysis. The detection of trace quantities of drugs may be employed for monitoring the rate of metabolism and for ascertaining the various metabolites produced by metabolism of drugs in the body.

Method for detecting trace quantities of an organic drug material in a living animal

For treating a fluid sample for introduction to a mass spectrometer or other appropriate use, a composite membrane and support assembly allows analytes from a sample flow to permeate through a membrane free from the undesired background matrix. The composite membrane and support assembly comprises a semipermeable membrane, a fiber member for supporting the membrane, and a rigid perforated member for supporting the membrane and the fiber support.

Composite membrane and support assembly

The invention provides a method and apparatus for efficiently measuring and analyzing volatile and relatively non-volatile flavor components released during oral processing of food or other products. The subject exhales a breath sample into one or more temperature-controlled collection chambers (12), preferably at predetermined time intervals during the oral processing of the product. Each breath sample is then purged from its collection chamber (12) with a non-reactive gas flow into an adsorbent, absorbent or other trap (30) containing an interface that separates and collects the volatile and relatively non-volatile components from the breath sample. The trap (30) is then transferred to a thermal desorber (36) to release the volatile and relatively non-volatile flavor components from the interface surface into a measuring and analysis apparatus (32,34).

Method and apparatus for measuring volatiles released from food products

A device for sensitive analysis of unknown organic samples is disclosed. The device is particularly useful as an interface between a gas chromatograph and a mass spectrometer which has a high pumping capacity. The device comprises an interface internal to the mass spectrometer which may either be attached directly to an inlet probe inserted into a mass spectrometer or directly to the source body of a mass spectrometer. In both cases, the sample goes directly into the source cavity and an auxiliary vacuum system is not required for sample enrichment. For mass spectrometers with marginal pumping capacity, or when very low source pressures are required, the vacuum system may be augmented by designs which either partially or completely isolate the source and interface exhaust pumping systems from each other.

Internal mass spectrometer interface to a gas chromatograph

Method and apparatus are provided for analysis of a sample of matter for at least one isotopic constituent of the sample. The method involves introduction of a sample containing an isotope of interest into an analytical detector operative to convert the sample into a product analyzable by a mass spectrometer and to detect a property of the sample representative of the quantity of at least one of its constituents, and passing the conversion product from the detector to a mass spectrometer operative to detect the isotopic ratio of interest. The method optionally includes passing the sample or a source material through a chromatograph column for separation into suitable fractions. The apparatus includes an appropriate analytical detector and a mass spectrometer with optional chromatography column. The method and instrument are particularly suited for analysis of oil-related samples such as crude oil fractions, natural gas, soil gas and oil shale as a tool in oil prospecting.

Llewellyn Peter Merlyn

Papers

Dual stage membrane gas separators with variable conductance means for varying their throughput