www.promochrom.com
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Online SPE for water analysis
Online SPE for Direct Analysis of Water Samples
Online SPE
is for direct analysis
of water samples. It combines
sample extraction and LC or LC-
MS analysis.
1. Working principle
The online SPE uses valves and a
syringe pump to transfer sample to
SPE column and then to the HPLC
system.
The control software looks after the
detailed valve switches. Users only
need to select the necessary
actions. Such as “load sample”,
“add reagent 1”, “inject”, “start
LC”, etc. The device uses remote
signal to trigger start of HPLC.
While the HPLC is running a
sample, online SPE can carry out
extraction of next sample. The
overlapped introduction saves
the time for sample preparation.
2. Applications
Below is an example for direct
analysis of polycyclic aromatic
hydrocarbons (PAH) in tap water at
ppt level. A 40-mL tap water is
analyzed directly. Since the whole
portion of the sample is injected to
the analytical column, the detection
limit can go down to 5 ppt without
using fluorescence detection. By
using the overlapped injection
feature, the processing time for one
sample is only 15 minutes.