Sample preparation by solid phase extraction

摘要

A flow control assembly for use in preparation of samples for analysis by solid phase extraction includes a housing assembly having a first passage communicating with a needle bore and locating a solid phase sorbent, a second fluid port, and a valve for selective aspiration or delivery of fluid across a solid phase sorbent, or bypassing the solid phase sorbent. Independent flow paths are provided for a sample via the needle, and of the elution solvent via a separate port. The valve includes relatively slideable first and second members, the second member including an elongate shank that is relatively reciprocably slideable for effecting selective aspiration or delivery of fluid between first and second relative positions. A third fluid port may be provided communicating with the elongate second passage for selective fluid communication with a port in a shank when the shank is at the second relative position.

主权项

1. A flow control assembly for use in preparation of samples for analysis by solid phase extraction, comprising:
a housing assembly adapted to be fitted as a coupling between a syringe barrel having a barrel chamber therein and a syringe needle that has a needle bore extending therealong and defines a first fluid port at its tip, which housing assembly includes structure defining a first passage arranged to be in fluid communication with the needle bore at its inner end and to locate a solid phase sorbent that contacts fluid traversing said first passage and adsorbs predetermined species; a second fluid port in said housing assembly; and a valve arrangement for selectively communicating the barrel chamber with said first passage and thereby with the needle bore or with the second fluid port for facilitating selective aspiration or delivery of fluid to or from said first fluid port across said solid phase sorbent or to or from said second fluid port bypassing the solid phase sorbent.