Comparison of different types of stationary phases for the analysis of soy isoflavones by HPLC

Fast Analysis of Bioactive Compounds by Reverse Phase Liquid Chromatography

“…For example, mixtures of water/acetonitrile show maximum viscosity at 35% (v/v) while water/methanol show the highest viscosity near 50% of each component (35). Furthermore, as can be observed in Figure 3, water/acetonitrile mixture produce a much lower difference in the pressure when compared to mixtures of water/ methanol (18). Nevertheless, acetonitrile is convenient for HPLC/MS methods because of the lower level of total volume of gases generated related to methanol based methods.…”

“…Acetonitrile present lower viscosity than methanol and therefore generate a lower column backpressure which in turn allows the use of higher flow rates. This aspect can be observed in Figure 3, where the allowed flow rate by the mobile phase composed by acetonitrile was almost 30% higher than the flow rate allowed by the mobile phase composed by methanol (18).…”

“…The conceptual design of these columns is to reduce analysis time through low column backpressure and high efficiency, allowing high flow rates, and faster transfer kinetics. Using monolithic columns it is possible explore flow rates that are 2 to 3 times higher than those allowed with columns of the same dimensions packed with totally porous particles of 3.5 µm or with partially porous particles of 2.7 µm (Figure 3) (18). In this case, the large pores (2μm) allow the application of high eluent flow rates due to the low flow resistance while the small pores (about 12nm) provide higher separation efficiency because of the high surface area (9,10).…”

Qualitative and quantitative determination of ten iridoids and secoiridoids in Gentiana straminea Maxim. by LC-UV-ESI-MS

“…In RP-HPLC, the elution ability of acetonitrile is better than methanol. Separation could be achieved in less time using acetonitrile than using methanol [23], but there may not be ideal separation in the reduced time using acetonitrile owing to more analytes. Also, the compounds with moderate polarities may have good solubility and separation in the system containing methanol and water.…”

“…In previous reports, the qualitative and quantitative determination and the fingerprintings of iridoids and secoiridoids in G. straminea and other Qinjiao herbs were undertaken using the HPLC method [17][18][19][20][21][22][23]. However, most scholars studied the simultaneous quantitative determination of gentiopicroside, loganic acid, swertiamarin, and sweroside in Qinjiao plants.…”