Ref. Analytical column (length mm × i.d. mm, particle size μ m) Elution type Flow rate (mL/min) Retention time (min) [1 ] Inertsil ODS-3v (250 × 4.6, 5) Isocratic 1.5 5.82 [2 ] PartiSphere 5 C18 (250 × 4.6, 5) Gradient 1.0 10.95 [10 ] Fused core Kinetex C18 (100 × 4.6, 2.6) Gradient 2.2 1.79 [13 ] Poroshell 120 EC-C18 (50 × 4.6, 2.7) Isocratic 0.5 5.0 [15 ] BDS HypersilGold C18 (250 × 4.6, 5) Isocratic 1.4 8.2 [15 ] Merck monolithic Rp-18 e (100 × 4.6) Isocratic 1.4 2.6 [19 ] Chromolith SpeedRod (50 × 4.6) Isocratic 3.0 0.68 [20 ] Hexyl methacrylate monolith (150 × 0.53) Isocratic 0.041 1.16 [20 ] Betasil C18 (150 × 4.6, 3) Isocratic 0.5 15.41 [37 ] Kinetex C18 (150 × 4.6, 5) Gradient 1.0 11.71 [38 ] UPLC C18 BEH (50 × 2.1, 1.7) Isocratic 0.7 2.52 [39 ] Eclipse XDB-C8 (150 × 4.6, 5) Isocratic 1.0 2.1 [40 ] Agilent TC-C18 (250 × 4.6, 5) Gradient 0.75 38.0 [41 ] BEH HILIC C18 (50 × 2.1, 1.7) Isocratic 0.25 1.15 [42 ] Eclipse C18 (250 × 4, 5) Gradient 1.0 10.0 [43 ] Scherzo SS-C18 (150 × 4.6, 3) Gradient 0.4 12.6 [44 ] Diol-HILIC (150 × 3.0, 5) Gradient 0.3 4.1 [45 ] XBridge C18 (150 × 4.6, 3.5) Isocratic 1.0 7.16 [46 ] Gemini C18 (150 × 4.6, 5) Gradient 1.0 18.6 [47 ] BEH C18 (100 × 2.1, 1.7) Gradient 0.25 4.24 [48 ] Kinetex C18 (100 × 2.1, 2.6) Gradient 0.2 3.6 [48 ] HypersilGold (50 × 2.1, 1.9) Gradient 0.2 1.9 [49 ] Titan C18 (100 × 2.1, 1.9) Gradient 0.3 6.81 This work Nucleodur C18 polar Tec. (50 × 2, 1.8) Isocratic 0.5 0.46