A: The short answer is no. High pressure is not the goal; it is simply a consequence of using small particle (sub-2m) HPLC columns. The use of these types of columns subjects hardware to greater stress due to increased resistance to flow and, subsequently, dramatically increases the back pressure, potentially sacrificing basic performance due to design constraints brought on by the need for a high pressure tolerance.
Q: Does high pressure influence consumable parts and maintenance?
A: Pushing any system to the extremes of its performance envelope, but particularly specialized systems running at higher pressures, increases stress on instrument components such as pump pistons and seals and the autosampler rotor and stator. This results in shorter consumable life and less durability even when using such specialized (more expensive) components.
Q: How does high pressure influence peak shape?
A: Under high-pressure conditions, frictional heating occurs in the column, causing a temperature gradient within the columns cross section. This means the mass transfer between the mobile phase and the packing material will be different across that area, possibly resulting in peak distortion. In such situations, any benefits to using high pressure are lost.