User manual

68 1200 Series Variable Wavelength Detector User Manual
5 How to optimize the detector
Traditionally LC analysis with UV detectors is based on comparing
measurements with internal or external standards. To check photometric
accuracy of the Agilent 1200 Series VWD it is necessary to have more precise
information on path lengths of the VWD flow cells.
The correct response is:
expected response * correction factor
Please find below the details of the Agilent 1200 Series VWD flow cells:
Figure 27 Influence of Cell Path Length on Signal Height
Absorbance
Time (min)
Analysis of pesticide standard
10-mm optical path length
6-mm optical path length
Table 11 Correction factors for Agilent 1200 Series VWD flow cells
Flow cell type Cell
volume
Part number Path length
(nominal)
Path length
(actual)
Correction
factor
Standard flow cell 14 µl G1314-60086 10 mm 10.15 ± 0.19 mm 10/10.15
Semi-micro flow cell 5 µl G1314-60083 6 mm 6.10 ± 0.19 mm 6/6.10
Micro flow cell 1 µl G1314-60081 5 mm 4.80 ± 0.19 mm 5/4.8
High Pressure flow cell 14 µl G1314-60082 10 mm 10.00 ± 0.19 mm 6/5.75
NOTE
However you have to be aware that there are additional tolerance of gasket thickness and
its compression ratio which is supposed to be very small in comparison with the machining
tolerance.