Chromatographic Conditions Variation Retention time
DBPN SBZ MP PP
Temperature (°C) 22 15.781 3.337 4.235 7.543
30 17.019 3.598 4.712 8.135
Flow rate (ml/min.) 0.8 20.949 4.426 5.842 9.936
1.2 13.960 2.937 3.882 6.638
Amount of Acetonitrile (%) 48 15.972 3.543 4.566 7.782
52 15.398 2.897 3.959 7.165
Table 4: Robustness of the method.