Studies on the retention behavior of quercetin, phenol, and caffeine as test substances on selected neutral and charged hydrophilic interaction liquid chromatography stationary phases

Abstract

The influence of mobile phase composition and column temperature on the retention behavior of quercetin, phenol, and caffeine as test analytes was analyzed. The experiments were conducted in columns filled with the charged amine phase and the neutral amide phase. As mobile phases, the varying fractions of methanol or acetonitrile in water solutions were applied. The most likely retention mechanisms have been discussed. The results of investigations confirm the importance of a mixed adsorption‐partition retention mechanism in the hydrophilic interaction liquid chromatography process, regardless of the mobile phase composition and type of stationary phase. Investigations have also shown that in the tested systems the retention mechanism is also strongly column temperature‐dependent. Additionally, the efficiency of the tested columns was determined and analyzed as a function of the linear flow velocity. The obtained literature known as van Deemter plots confirms generally higher column efficiencies in the systems with acetonitrile as an organic component of the mobile phase. However, in some cases, the application of methanol allows obtaining similar column efficiencies. Furthermore, the results show that both columns tested exhibit comparable efficiency in the most tested systems and provide very good efficiency preservation over the wide range of eluent velocities.

Studies on the Effects of Process Conditions on Separation of B1, B2 and B3 Vitamin Mixture Using HILIC and RPLC Chromatography

“…Due to the increased interest in the simultaneous determination of the water-soluble vitamins (WSVs), methods, such as capillary electrophoresis techniques [8][9][10], and chromatographic techniques, such as thin-layer chromatography [11], micellar electrokinetic chromatography [12][13][14], micellar liquid chromatography [15], pressurized capillary electrochromatography [16] and high-performance liquid chromatography (HPLC), were used, with the last one being of the greatest interest due to apparatus improvements and a variety of stationary phases and eluents. Among the HPLC techniques, reversed-phase chromatography (RP-HPLC) has been applied most often for simultaneous determination of the VSWs due to simplicity and enhanced efficiency of the stationary phases [7,[17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. However, the chromatographic separation of the WSVs under isocratic conditions is possible only for a mixture of two or three vitamins [17,18], while the simultaneous chromatography of more complicated mixtures usually requires a gradient elution involving buffer phases [19][20][21][22][23][24][25][26][27] or specialized detection techniques [28].…”

“…The HILIC method proposed by Alpert [29] in 1990 is considered to be a technique enabling the analysis of polar and medium polar compounds and an alternative method to previously used normal phase (NPLC) and reversed-phase (RPLC) liquid chromatography. Within the past few decades, the HILIC technique has filled the gap between the RPLC and NPLC, providing effective separation of the compounds that caused difficulties and were hitherto associated with unsatisfactory results when analyzed under the RP [30,31] or the aqueous conditions [32]. Generally, the HILIC mixed-mode retention mechanism assumes partitioning of the polar solute between the mobile eluent and a layer of the water-enriched mobile phase immobilized on the polar stationary phase [29,[33][34][35].…”

Studies on the Effects of Process Conditions on Separation of B1, B2 and B3 Vitamin Mixture Using HILIC and RPLC Chromatography

“…The hydrophilic interaction liquid chromatography (HILIC) proposed by Alpert [1] in 1990 is considered as a technique enabling the analysis of polar and medium polar compounds and as an alternative method to previously known the normal phase (NPLC) and the reversed phase (RPLC) liquid chromatography. Within the past decades the HILIC technique has filled the gap between the RPLC and the NPLC providing effective separation of the compounds that caused difficulties and were hitherto associated with unsatisfactory results when analyzed under the RP [2,3] or the aqueous conditions [4]. Generally, the HILIC mixed mode retention mechanism assumes partitioning of the polar solute between the mobile eluent and a layer of the water-enriched mobile phase immobilized on the polar stationary phase [1, [5][6][7].…”