Thermo Scientific IonPac CG16, Руководство по эксплуатации продукта

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Product Manual for IonPac CS16 Page 13 of 65
3.4. The Injection Loop
Table 5
Smallest Injectable Volumes (µL)
Valve Type Using 0.012” ID
Tefzel Tubing
Using 0.007” ID
Tefzel Tubing
Using 0.010” ID
PEEK Tubing
Using 0.005” ID
PEEK Tubing
Dionex
BF2 Valve
(8 µL Internal Volume)
(10 cm Loop) 15.2 10.5 13.1 9.2
Dionex
MicroInject Valve
(10.5 µL Internal Volume)
(14 cm Loop) 20.5 14.0 17.6 12.2
Dionex
Microinjection Valve
Model 9126
(0.8 µL Internal Volume)
(10 cm Loop) 8.0 3.3 5.9 2.0
For most applications on a standard bore analytical system, a 10–50 µL injection loop will be sufficient. Dionex recommends
that a 10 µL injection loop be used to avoid overloading the CS16 5-mm Analytical Column. Generally, do not inject more
than 10 nanomoles (100–200 ppm) of any one analyte onto the 5-mm analytical column. Injecting larger volumes of samples
can result in overloading the column which can affect the detection linearity. This phenomenon will be more prevalent at
higher concentrations of the analytes of interest. In the case of the CS16 3-mm, do not inject more than 4 nanomoles (35–70
ppm) of any one analyte onto the 3-mm analytical column.
3.5. Sample Concentration
The IonPac CG16 Guard Column or the Low-Pressure Trace Cation Concentrator, TCC-LP1, should be used for trace cation
concentration. Trace cation concentrators are used primarily in high purity water analysis. The function of a trace cation
concentrator in these applications is to strip ions from a measured volume of a relatively clean aqueous sample matrix. This
can be accomplished by concentrating large volumes of the sample onto a concentrator column and then using this column in
place of the sample loop. The sample should be pumped into the concentrator column in the OPPOSITE direction of the
eluent flow, otherwise the chromatography will be compromised. This process “concentrates” all cationic analyte species
onto the trace cation concentrator (the TCC-LP1 or the CG16) leading to a lowering of detection limits by 2–5 orders of
magnitude. The unique advantage of the trace cation concentrator (TCC-LP1 or the CG16) for the analytical chemist in these
applications is the capability of performing routine trace analyses of sample matrix ions at ng/L levels without extensive and
laborious sample pretreatment.
The IonPac CG16 5-mm Guard Column (P/N 057574) or the Low-Pressure Trace Cation Concentrator (TCC-LP1, P/N
046027) should be used for sample concentration with the IonPac CS16 5-mm Analytical Column. The IonPac CG16 3-mm
Guard Column (P/N 059595) or the Low-Pressure Trace Cation Concentrator (TCC-LP1, P/N 046027) should be used for
sample concentration with the IonPac CS16 3-mm Analytical Column. For the Trace Cation Concentrator to work with the
CS16 0.5 mm Column use the CG16 0.5 mm Column or the IonSwift MCC-100 (0.5 x 80 mm) or MCC-200 (0.75 x 80 mm)
Concentrator Column.
CAUTION
!
The Trace Cation Concentrator (TCC-2, P/N 043103) should NOT be used for sample concentration. The
TCC-2 column packing is a strong cation exchange resin functionalized with sulfonic acid. The
recommended IonPac CS16 eluents will not properly elute ions concentrated on this column.
Document No. 031747-05 © 2010 Dionex Corporation December 2010