title: Practical method transfer from high performance liquid chromatography to ultra-high performance liquid chromatography: the importance of frictional heating.
abstract: In theory, with identical stationary phase chemistry, the transfer of an HPLC method to UHPLC conditions is straightforward and necessitates the calculation of new conditions based on column and instrument geometries. Occasionally, undesirable changes in selectivity, retention or efficiency have been reported and have been attributed to a frictional heating phenomenon that is due to the elevated generated pressure drop. In the present study, the frictional heating in a UHPLC system was evaluated experimentally under gradient elution conditions (acetonitrile/buffer at pH 3 and 9) with generated pressure drops in the range of 100-1000 bar on both 1.0mm and 2.1mm I.D. columns using a mixture of 10 representative basic, acidic and neutral pharmaceutical compounds. Under adiabatic conditions (i.e., still-air oven), the longitudinal temperature gradient was estimated at +4 °C, +8 °C and +16 °C at 300, 600 and 1000 bar, respectively, on a 2.1mm I.D. column using an empirical measurement procedure. With the 1.0mm I.D. column, these values were reduced to +3 °C, +6 °C and +12 °C, respectively. Finally, various approaches to eliminate or at least to reduce the effect of frictional heating are briefly discussed.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Nováková
authors.forename: Jean Luc
authors.initials: JL
authors.lastname: Veuthey
authors.forename: Davy
authors.initials: D
authors.lastname: Guillarme
mesh_terms: D002021:Buffers; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D017276:Friction; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D004364:Pharmaceutical Preparations / Q000737:chemistry / Q000302:isolation & purification; D011312:Pressure
chemical_list: D002021:Buffers; D004364:Pharmaceutical Preparations