syringe pump - a popular and useful pump design for Micro-LC and SFC, consists of a single, large volume cylinder and piston assembly (typically 50 mL in volume), such that uninterrupted mobile phase flow is available without pulsation.

See syringe pump.

tailing - the phenomenon in which the normal Gaussian peak has an asymmetry factor more than 1. The peak will have skew in trailing edge. Tailing is caused by sites on the packing that have a stronger-than-normal retention for the solute. A typical example of a tailing phenomenon is the strong adsorption of amines on the residual silanol groups of a low-coverage reversed-phase packing.

theoretical plate - one equilibrium between the mobile and stationary phase; a measure of column efficiency; the more plates, the better the column efficiency.

See band broadening.

total permeation volume (Vp) - the retention volume on an SEC packing in which all molecules smaller than the smallest pore will elute. In other words, at Vp, all molecules totally permeate all of the pores and elute together. Total permeation volume is usually equal to the dead volume.