Michael McGinley | Authors


Protein Aggregates and Gel Filtration Chromatography: Improving Quantitation and Throughput of a UHPLC Method

Gel filtration chromatography (GFC) is the most widely used method for quantitating protein aggregates in therapeutic drugs. It is a simple method, but prone to error as a result of poor method development and column selection. GFC columns tend to non-specifically adsorb large proteins and aggregates resulting in poor quantitation of “true” aggregate amount. Sample “priming” and mobile phase optimization can help reduce such irregularities. Simple method development rules using new column technologies are presented that demonstrate improved accuracy for these methods.

Evaluating Particle Size and Back Pressure in Peptide Mapping by UHPLC

Ultrahigh-pressure liquid chromatography (UHPLC) columns are used in peptide mapping to improve the resolution of highly complex peptide mixtures. It is commonly assumed that small particle columns increase performance, but this is not always the case. This study presents a comparison of peak count, column length, and resolution between core–shell and fully porous UHPLC columns.

Optimizing Gel Permeation Chromatography for Analyzing Polymers used as Drug Excipients

Although gel permeation chromatography (GPC) is not as widely used as other chromatography methods, it continues to be a useful technique for analyzing the size and solution characteristics of organic polymers. In this study, GPC was applied to analyze different polar polymers that are commonly used in drug excipients. As a result of their polarity, some specialized operating conditions were required. Optimizing the separation brought to light many of the common parameters involved in optimizing GPC separations, and those are discussed in detail here.