Method and equipment for volumetrically controlled and reproducible introduction of small amounts of liquid samples into chromatographic analysis systems

摘要

A method and apparatus for controllably and reproducibly introducing small amounts of a liquid sample into chromatographic systems, especially high resolution gas chromatographic systems and thin-layer chromatographic systems, order to obtain sampling extremely reduced in volume and presenting maximum reliability and reproducibility, uses a sample container having a pipette-like or nozzle-like outlet neck of very small diameter. The liquid placed in the container is submitted to at least one pressure pulse which is controlled in time and/or amplitude in order to determine emission of a corresponding and controlled quantity of liquid from the outlet neck. The pressure pulse can be a pneumatic pulse directly applied to the liquid sample in the container, or a mechanical pulse applied to the liquid sample through a device acting by magnetostriction or by a piezoelectric system.