Patent ID: 8070957

Claim:
A method for low pressure liquid chromatographic analysis of a material using a liquid chromatographic cartridge kit assembled by a user of the kit, said kit including a hollow cylindrical polymer container and a polymer cap with a fluid inlet for attachment to one end of said container by the user to form a chromatographic cartridge, wherein said container includes a fluid outlet at another end thereof and has a chromatographic packing material placed therein before said kit is obtained by the user, said packing material having a surface spaced from said one end of said container to form a predetermined volume between said surface and said cap sufficient to hold a sample for chromatographic analysis when said cap is attached to said container, and said container further includes a threaded portion on an external surface thereof proximate to said one end and said cap comprises a depending skirt having a threaded portion on an internal surface thereof for engaging said threaded portion on said container, the method comprising: placing the sample in said volume; thereafter screwing said cap onto said container into a final position by engaging said respective threaded portions to provide a seal between said container and said cap capable of withstanding pressures up to about 100 psi, said seal being formed between (a) an inner surface of said container proximate to said upstream end thereof, said container including an inclined lip portion surrounding said inner surface of said upstream end, and (b) a cap flange disposed for accepting said container between said skirt and said flange with said inclined container lip portion contacting said cap flange to urge said flange inwardly toward said longitudinal axis as said cap is screwed onto said container and into said final position; attaching a low pressure liquid chromatographic apparatus to said inlet for introducing chromatographic process fluid into said inlet under a pressure up to about 100 psi; and introducing said chromatographic process fluid from said outlet to said low pressure liquid chromatographic apparatus for analysis.