Retention time precision of Agilent 1290 Infinity Quaternary Pump Analysis of clopidol using dynamically and premixed gradients

The most important performance parameter for an ultrahigh performance liquid chromatography (UHPLC) pump is precision of retention times. Highest precision is required to identify compounds by retention times and subsequently accurately quantify the analyzed sample compounds. Gradient analysis can be done using either premixed mobile phases applying gradients from 0 to 100% B, as described in some USP methods, or using dynamically-mixed mobile phases applying gradients, for example, from 10 to 80% B. This Technical Overview shows that premixing mobile phases for gradient applications provides retention time precisions below specifications, even under demanding chromatographic conditions. It also shows that dynamically-mixed gradients with the Agilent 1290 Infinity Quaternary Pump improve retention time precision significantly. The results of the 1290 Infinity Quaternary Pump are compared to results obtained using a quaternary pump from a non-Agilent manufacturer. Author Angelika Gratzfeld-Huesgen Agilent Technologies, Inc. Waldbronn, Germany min 6.2 6.4 6.6 6.8 7 7.2 7.4 7.6 250 300 mAU 0 50 100 150 200 Dynamically mixed gradient RSD RT = 0.015%