International Journal of Analytical Chemistry / 2015 / Article / Tab 1 / Research Article
Comparison of Electrospray Ionization and Atmospheric Chemical Ionization Coupled with the Liquid Chromatography-Tandem Mass Spectrometry for the Analysis of Cholesteryl Esters Table 1 Time-scheduled SIM conditions,
ions and corresponding structures used in the LC-ESI-MS/MS analysis of CEs.
Compound Retention time (RT, min) Molecular weight (Mw)
SRM transitions ( ) Precursor ion → Product ion Coll. energy (v) Corresponding structure NL Fatty acid ESI APCI ESI APCI ESI APCI ESI APCI Chl-butyrate 7.02 456.8 479.4 → 119 457.5 → 105.20 40 62 M+Na]+ M+H]+ 2.82E + 03 1.22E + 02 4:0 479.4 → 369 457.5 → 369 5 7 Chl-valerate 7.69 470.8 493.4 → 105 471 → 369 39 20 M+Na]+ M+H]+ 8.14E + 03 9.54E + 01 5:0 493.4 → 369 — 9 Chl-heptanoate 8.93 498.8 521.4 → 147 499.6 → 369 31 8 M+Na]+ M+H]+ 1.28E + 04 1.14E + 01 7:0 521.4 → 369 — 9 Chl-caprylate 9.77 512.8 535.5 → 147 514 → 369 22 10 M+Na]+ M+H]+ 1.44E + 04 2.94E + 01 8:0 535.5 → 369 — 13 Chl-nonanoate 10.64 526.9 549.5 → 105 528 → 369 42 5 M+Na]+ M+H]+ 1.24E + 04 6.03E + 01 9:0 549.5 → 369 — 10 Chl-caprate 11.64 540.9 563.5 → 107 542 → 369 30 11 M+Na]+ M+H]+ 1.50E + 04 2.88E + 02 10:0 563.5 → 369 — 18 Chl-undecanoate 12.51 555 577.5 → 161 556 → 369 32 8 M+Na]+ M+H]+ 1.76E + 04 3.42E + 02 11:0 577.5 → 369 — 14 Chl-laurate 13.68 569 591.5 → 161 570 → 146.9 32 32 M+Na]+ M+H]+ 1.50E + 04 1.40E + 03 12:0 591.5 → 369 570 → 369 13 10 Chl-arachidonate 13.98 673.11 690.6 → 109 674 → 147.14 43 36 M+NH4 ]+ M+H]+ 5.03E + 05 2.46E + 04 20:4 690.6 → 369 674 → 369 10 14 Chl-tridecanoate 15.09 583 605.5 → 105 584 → 369 46 10 M+Na]+ M+H]+ 1.22E + 04 1.96E + 02 13:0 605.5 → 369 — 13 Chl-linoleate 15.55 649.08 666.6 → 161 650 → 373.26 30 15 M+NH4 ]+ M+H]+ 2.77E + 05 1.14E + 04 18:2 666.6 → 369 650 → 361.26 9 15 Chl-palmitelaidate 15.92 623.05 640.6 → 108 624 → 335.21 35 15 M+NH4 ]+ M+H]+ 6.73E + 04 4.10E + 03 16:2 640.6 → 369 624 → 369 9 13 Chl-myristate 16.06 597 619.5 → 108 598 → 369 39 14 M+Na]+ M+H]+ 1.57E + 04 2.61E + 02 14:0 619.5 → 369 — 16 Chl-pentadecanoate 17.52 611.1 633.6 → 369 612 → 369 12 5 M+Na]+ M+H]+ 5.06E + 03 1.75E + 03 15:0 Chl-oleate 18.13 651.1 668.6 → 147 652 → 363.28 33 20 M+NH4 ]+ M+H]+ 1.62E + 05 8.79E + 03 18:1 668.6 → 369 652 → 369 8 11 Chl-palmitate 18.6 625.1 647.6 → 147 626 → 161.1 28 23 M+Na]+ M+H]+ 1.17E + 04 2.23E + 03 16:0 647.6 → 369 626 → 369 14 11 Chl-heptadecanoate 19.92 639.1 661.6 → 105 640 → 146.89 69 32 M+Na]+ M+H]+ 1.43E + 04 1.67E + 03 17:0 661.6 → 369 640 → 369 16 10 Chl-stearate 21.31 653.1 675.6 → 135 654 → 273.16 38 31 M+Na]+ M+H]+ 9.78E + 03 7.03E + 02 18:0 675.6 → 369 654 → 369 15 6 Chl-nonadecanoate 22.53 667.2 689.6 → 119 668 → 147 45 28 M+Na]+ M+H]+ 1.24E + 04 7.34 19:0 689.6 → 369 668 → 369 19 9 Chl-arachidate 23.85 681.2 703.6 → 335 682 → 228.75 16 33 M+Na]+ M+H]+ 7.32E + 04 6.00E + 02 20:0 703.6 → 369 682 → 369 15 5 Chl-heneicosanoate 25.14 695.2 717.7 → 349.5 696 → 272.6 17 31 M+Na]+ M+H]+ 5.94E + 04 2.92E + 03 21:0 717.7 → 369 696 → 369 19 14 Chl-behenate 26.39 709.2 731.7 → 363 710 → 386.13 17 14 M+Na]+ M+H]+ 6.73E + 04 1.82E + 03 22:0 731.7 → 369 710 → 369 23 9 Chl-lignocerate 28.49 737.3 754.7 → 132 738 → 108.96 50 28 M+NH4 ]+ M+H]+ 4.86E + 04 5.01E + 03 24:0 754.7 → 369 738 → 369 11 16