January 2021

Sometimes our approach to troubleshooting specific problems has to change in response to changes in high performance liquid chromatography (HPLC) technology over time. In this installment, we discuss changes in technologies for mobile-phase degassing, silica-based stationary phases, and models for reversed-phase selectivity.

Here are some great tips for optimizing liquid chromatography (LC)–electrospray ionization (ESI)–MS to achieve the best possible results every time. This is a beginner’s guide to LC-ESI–MS.

We investigate a phenomenon observed by many practitioners of reversed- phase LC: a dramatic loss in retention volume or time after the column flow is stopped and resumed when using highly aqueous mobile phases with certain columns.

Temperature is frequently employed to enhance analytical extractions, especially with solid samples or volatile analytes. Using temperature to enhance analytical extractions continues today with more recently developed techniques, which we explore.

For GC, how do data systems both assist and hinder us in obtaining maximum information from chromatograms? We explain how a chromatogram can provide a wealth of information about an individual analyte in a sample, about the sample itself, and about how well a GC instrument is performing.

New analytical workflows are needed to address the advances in biopharmaceutical product composition. A description of the multi-attribute method (MAM) is given, which has been developed to monitor critical quality attributes (CQAs) simultaneously and directly.