HPLC

Authors: Anne Marie Smith, Richard Lee, Alexey Galin, Andrey Vazhentsev

Introduction

Investment in systematic processes (such as Quality by Design processes) has improved the quality and efficiency of method development projects. But these processes still require significant repetitive labor. Automation can help improve productivity. Method development software can automatically generate lists of experiments for a user-defined design space, communicate with chromatography data systems (CDSs) to run those experiments, and perform some automated processing.

Here, we present a new automated processing method in AutoChrom software, featuring targeted MS based peak tracking.

Methods

A temperature- and gradient- optimization project was created in ACD/AutoChrom. Two peptides and their related impurities angiotensin I and melittin were used as model substances.  Chromatographic conditions: BEH C18 AX column (150 x 2.1 mm, 1.7 μm), 0.1% TFA in water (A eluent) and acetonitrile (B eluent), 30-95%B at 0.4 mL/min, diode array and single quadrupole MS detection.

Nine experiments: 3 temperatures (30, 45, and 60 °C) and 3 gradient times (19, 39, and 58 minutes).

For automated processing, AutoChrom was provided with the masses of target compounds (manually determined from the run with the best separation) and peak picking parameters.

Results

The new processing algorithm presents a significant improvement to the post-experiment automation within AutoChrom. The automated targeted peak tracking and identification algorithm found all compounds of interest and peaks not of interest did not clutter peak tables.

Targeted peak tracking improved the automated results for isobaric compounds, which are challenging to monitor across chromatographic traces. Some manual review was still required, however, to separate coeluted isobaric compounds. The algorithm automatically produced extracted ion chromatograms from the masses in the target list simplifying the review process.

The new method for processing LC/MS data provides a good balance between automation and autonomy. Initial processing is automated, reducing time spent on tasks like simple integration. But experts can intervene as necessary to correct/refine results. Users can define a list of targets to track across chromatograms, focusing only on compounds of interest. Finally, reports can be generated quickly and results databased for future use.