Patent ID: 6989129

Claim:
An automatic capillary liquid chromatography chemical analysis system comprising, in combination, a capillary defining a fluid passageway having an inlet end, and outlet end, and an intermediate branch outlet, said capillary being filled with a porous material to form a trapping pre-concentration column between said inlet end and said intermediate branch outlet and a separation column between said branch outlet and said outlet end, loading flow control means coupled to said inlet end and to said branch outlet for passing a liquid sample through said trapping pre-concentration column, analysis flow control means for terminating the further introduction of said liquid sample into said pre-concentration column via said inlet end and for thereafter passing a concentrated liquid sample from said pre-concentration column through said separation column at a separation flow rate between 10 and 1,000 nanoliters per minute to deliver chromatography eluent through said outlet end, and an analyzer positioned at said outlet end for receiving and analyzing said chromatography eluent delivered from said separation column via said outlet end.