High Performance Liquid Chromatography, popularly known as HPLC, had some common benefits that users looked forward to and these were such as high resolution, high sensitivity and the speed of analysis that it had to come with. The interesting bit in all this is the fact that most of these, if not all, benefits looked forward in HPLC, actually became a reality when the UHPLC, Ultra High Performance Liquid Chromatography came in.
By far and large, column efficiencies were known to increase with the reduction of the particle sizes. By and large, in the conventional analytical separations, the particle sizes used would often be between the ranges of 3 and 5 nanometers. 2 nanometer was seen as a subpar barrier. This be as it was, the barrier was broken in later years and there were actually demonstrated columns packed with the 2 nanometer particle sizes. By and large, it is with this particular development that we actually saw the final coming in of the Ultra High Performance Liquid Chromatography, UHPLC, in the whole chemistry of analytical separation.
As we seek to understand this better, we will be taking a look at some of the basic differences there are between UHPLC and the conventional HPLC.
As we look at these key differences, we start by looking at the column dimension differences. The UHPLC columns have actually been found to be much shorter and a lot narrower as compared to what would be with the HPLC columns in a general sense. Analytical columns are in most cases up to 4.6mm ID by 250mm length while the UHPLC columns would be 2.1mm ID by 50mm long.
Another notable key difference there is between these two is looking at their operating pressure capacities. In this, it is to be noted that the UHPLC columns can actually handle higher pressure limits, up to 18000 psi, as compared to the analytical pressure range that doesn’t go beyond 6000 psi. Actually, the pumps will be able to handle such extreme pressure conditions with the least of effects of wear and tear on their parts.
Not to forget mention the fact of better detection with the UHPLC columns. The reason for this is looking at the fact that the UHPLC columns produce rather fewer peaks as compared to the HPLC columns which have lesser number of data points as such being rather poor in detection.