Samples to be analyzed should be injected to the microcolumns
through the S ports using peristaltic pump(s). It is possible to inject
even 12 different samples parallelly to separate chromatographic packings
(6- or 8-channel peristaltic pumps are quite common in themarket).
Then, the adsorbed (preconcentrated) Cr(VI) can be eluted from the
microcolumn by pumping the eluent from the common port E (elution