Characterization of triacylglycerols in the seeds ofAquilegia vulgaris by chromatographic and mass spectrometric methods

Abstract

A combination of analytical techniques is generally necessary to properly characterize complex lipid materials. Chromatographic separation in conjunction with spectroscopic characterization was utilized for the analysis of the triacylglycerols in the seeds ofAquilegia vulgaris. Reversed-phase high-performance liquid chromatography (HPLC), micropacked argentation supercritical fluid chromatography (SFC), and combinations of the two techniques were used. The fatty acid profile was determined by gas chromatography/mass spectrometry of the picolinyl esters and by gas chromatography/flame-ionization detection of the methyl esters. The major components were also identified by direct inlet mass spectrometry. The excellent selectivity of packed fused silica argentation SFC for the separation of triacylglycerols was demonstrated.

Stationary phases for silver ion chromatography of lipids: Preparation and properties

“…In general, under the conditions applied in most SFC experiments, the stationary phase shows excellent stability. Leakage of silver ions has been reported, however, if the mobile phase contains components that can displace silver ions from the active sites of the supporting material (chloroform, for example) [97]. These silver loaded stationary phases show good thermal stability, and retentive properties remain unchanged after conditioning at 1308C and 300 atm for 24 h [99].…”

“…The SFC columns with silver loaded Nucleosil TM SA enabled the resolution of FAME differing in number and configuration of the double bonds [97,98]. Resolution of the two positional isomers, 20:4(n-6) and 20 : 4(n-3) (eluting in this order), has been achieved as well (Figure 7).…”

“…Demirbuker and co-workers [97] have outlined several advantages of these columns in lipid analysis: (i) excellent separation efficiency; (ii) low thermal mass, an advantage when employing temperature programming; (iii) the low flow of mobile phase, which greatly simplifies preheating of the mobile phase in temperature programmed runs and facilitates the connection to MS; (iv) cheap preparation. In addition, the low mobile phase consumption results in generally lower costs.…”

“…Columns are prepared from fused silica capillary tubing (Chrompack) of 160 mm [99], 250 mm [98], 290 mm [100], or 330 mm [101] length with 0.25 mm inner diameter, with 0.05 mm silica for the transfer lines. The packed bed is supported by glass fibre filters, and the transfer line to the detector is attached to the column by epoxy glue [99].…”

“…The stationary phase for Ag-SFC is the same as in Ag-HPLC: silica-based cation exchanger Nucleosil TM 4SA [97,98] or Nucleosil TM 5SA [99 -102] loaded with silver ions. Columns are prepared from fused silica capillary tubing (Chrompack) of 160 mm [99], 250 mm [98], 290 mm [100], or 330 mm [101] length with 0.25 mm inner diameter, with 0.05 mm silica for the transfer lines.…”