Sharp Peaks, Low Backpressure: Filtration of Sample Extends the Life Time of Your HPLC Column and Improves Separation Performance

摘要

Today HPLC is standard in a broad range of application fields, e.g. separation of complex mixtures of proteins or amino acids or identification and quantification of organic molecules or inorganic ions. The trend to miniaturisation and increased sensitivity in HPLC requires paying more attention on the technical equipment. Small diameter columns with IDs of 1 mm or less are very vulnerable to damage and misuse, especially if they are packed with media in the range of 1-3 (mu)m in particle size. Sample preparation is one factor to extend the life time of the columns and keep their performance on a high level, but it is crucial to time, costs and particularly the analytical result. Samples are the main source of particle contamination in HPLC columns. So, usually the last preparation step before sample injection into the HPLC-instrument is to remove small particulates from the sample by filtration. Elimination of solid materials is important, as those particles can interfere with the compound of interest and very easily clog up the separation column. This has an impact on the separation performance, i.e. back pressure, retention time, peak size and peak shape. In the worst case, the column is irreversibly blocked and has to be replaced. It is not just the replacement of the column that is an issue, because of downtime and additional costs, but also the loss of valuable samples might be of even greater importance for the operator.