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Agilent 1290 Infinity LC System Manual and Quick Reference
3
Optimization of the Agilent 1290 Infinity LC System
How to Configure the Optimum Delay Volume
For very fast gradients over 0.5 min, which can only be achieved in the Agilent
1290 Infinity Binary LC System, the delay volume of the system can be easily
reduced without changing the physical configuration of the system. This
change is achieved by changing the behavior of the autosampler.
The 80 µl delay volume of the Agilent 1290 Infinity Autosampler is due to the
flow path from the injection valve through the metering device, needle, needle
seat and connecting capillaries back to the injection valve (see
page 32). To make an injection the valve switches from mainpass to bypass so
that the metering device can draw the sample into the needle capillary. The
1.5
0.01
0.04
0.06
0.08
0.24
0.29
0.34
0.39
2.0
0.01
0.03
0.04
0.06
0.18
0.22
0.26
0.29
3.0
0.01
0.02
0.03
0.04
0.12
0.14
0.17
0.19
4.0
0.01
0.01
0.02
0.03
0.09
0.11
0.13
0.15
5.0
0.00
0.01
0.02
0.02
0.07
0.09
0.10
0.12
Table 7
Approximate volume of liquid in typical column dimensions assuming that
porosity = 0.6
Column
Diameter
(mm)
Column Length (mm)
30
50
100
150
250
Column Volume - Liquid Phase (microliters)
2.1
62 104
208
312
520
3.0
127
212
424
636
1060
4.0
226
377
754
1131
1885
4.6
299
499
997
1496
2493
Table 6
System delay times for gradient to reach head of column
Flow
Rate
(ml/min)
System Delay Volume (microliters)
