Early Studies in Ultrahigh Pressure Liquid Chromatography of Intact Proteins

The analysis of proteomic mixtures is quite complex due to the abundance of species to characterize. Most modern methods utilize a bottom-up approach, but as mass spectrometer methods improve, the need to high-resolution top-down methods have also been identified. The separation of intact proteins for top-down proteomics by reverse-phase liquid chromatography (RPLC) has received renewed interest due to the ease of coupling to ESIMS. Unfortunately, modern RPLC methods do not have high enough resolving power to analyze complex proteomic mixtures with great success. It has been well documented that the use of smaller diameter packing material in a chromatographic column can greatly increase the resolving power. These particles, which have a diameter of