Mateusz Imiołek

This article explores three case studies where autosampler injection programs help to (i) reduce the carry-over observed for large nucleic acids during anion-exchange chromatography (AEX), (ii) reduce peak distortion and breakthrough for monoclonal antibodies (mAbs) during hydrophilic-interaction chromatography (HILIC), and (iii) facilitate dissolution of lipid nanoparticles (LNPs) so that a size-exclusion chromatography (SEC) method can be applied for ribonucleic acid (RNA) payload analysis.

The purpose of this short tutorial article is to review the terms and official nomenclatures for size-exclusion separations and to provide some guidance and recommendations for practicing chromatographers. The interconversion between the different metrics is explained and some examples are presented.

Pressure-enhanced liquid chromatography (PE-LC) offers a new approach for improving selectivity for large molecule separations. Examples shown here include short oligonucleotides in ion-pairing reversed-phase (IP-RP) liquid chromatography and larger nucleic acids in ion-exchange (IEX) chromatography.