Technical data

44 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 Figure 18 on
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
Tabl e 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
Tabl e 6 System delay times for gradient to reach head of column
Flow
Rate
(ml/min)
System Delay Volume (microliters)