High throughput screening of drug impurity profiles using gradients in normal phase chromatography

Developmental drug substances and a variety of precursors and process-relat ed impurities were separated using mobile phase gradients under normal phas e conditions. These separation conditions produced efficient separations in a fraction of the time necessary for comparable reversed-phase separations . The use of elevated temperatures, polar modifiers and moderate levels of acidic and basic additives allowed highly polar analytes to be eluted with high efficiency and selectivity using fast flow rates. Reproducibility for retention time and peak areas was demonstrated to be very good despite very short equilibration times.