MilliporeSigma
  • Comparison of various second-dimension gradient types in comprehensive two-dimensional liquid chromatography.

Comparison of various second-dimension gradient types in comprehensive two-dimensional liquid chromatography.

Journal of separation science (2010-03-24)
Pavel Jandera, Tomás Hájek, Petr Cesla
ABSTRACT

Gradient elution provides significant improvement in peak capacity with respect to isocratic conditions. In the second dimension, gradients are limited to a short-time period available for separation. Various types of second-dimension gradients in comprehensive LC x LC are compared: (i) "full in fraction", (ii) "segment in fraction" and (iii) "continuously shifting" gradients, applied in orthogonal LC x LC separations of phenolic acids and flavones on a polyethylene glycol column in the first dimension and two types of porous shell fused-core C18 columns in the second dimension (Ascentis Express and Kinetex). The porous shell columns provide narrow bandwidths and fast second-dimension separations at moderate operating pressure that allows important savings of the overall separation time in comprehensive LC x LC separations. The effects of the gradient type on the bandwidths, theoretical peak capacity, separation time and column pressure in the second dimension were investigated. The type of gradient program controls the range of lipophilicity of sample compounds that can be separated in the second-dimension reversed-phase time period. This range can be calibrated using alkylbenzene standards, to design the separation conditions for complete sample separation, avoiding harmful wrap around of non-eluted compounds to the subsequent second-dimension fractions.

MATERIALS
Product Number
Brand
Product Description

Supelco
Ascentis® Express C18, 2 μm Guard Cartridge, 2 μm particle size, L × I.D. 5 mm × 2.1 mm, pkg of 3 ea
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 7.5 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 10 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 25 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 5 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 15 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 7.5 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 25 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 2 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 10 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 15 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 3 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 3 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 5 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 25 cm × 3 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 3 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 7.5 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 10 cm × 2.1 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 5 cm × 4.6 mm
Supelco
Ascentis® Express C18, 5 μm HPLC Column, 5 μm particle size, L × I.D. 15 cm × 2.1 mm
Supelco
Ascentis® Express C18, 2.7 Micron Capillary HPLC Column, 2.7 μm particle size, L × I.D. 5 cm × 500 μm
Supelco
Ascentis® Express C18, 2.7 Micron Capillary HPLC Column, 2.7 μm particle size, L × I.D. 15 cm × 300 μm
Supelco
Ascentis® Express C18, 2.7 Micron Capillary HPLC Column, 2.7 μm particle size, L × I.D. 5 cm × 300 μm
Supelco
Ascentis® Express C18, 2.7 Micron Guard Cartridge, 2.7 μm particle size, L × I.D. 5 mm × 4.6 mm, pkg of 3 ea
Supelco
Ascentis® Express C18, 2.7 Micron Guard Cartridge, 2.7 μm particle size, L × I.D. 5 mm × 2.1 mm, pkg of 3 ea
Supelco
Ascentis® Express C18, 2.7 Micron Guard Cartridge, 2.7 μm particle size, L × I.D. 5 mm × 3 mm, pkg of 3 ea
Supelco
Ascentis® Express C18, 2.7 Micron Capillary HPLC Column, 2.7 μm particle size, L × I.D. 15 cm × 500 μm
Supelco
Ascentis® Express C18, 2.7 μm HPLC Column, 2.7 μm particle size, L × I.D. 7.5 cm × 2.1 mm
Supelco
Ascentis® Express C18, 2.7 μm HPLC Column, 2.7 μm particle size, L × I.D. 3 cm × 2.1 mm
Supelco
Ascentis® Express C18, 2 μm UHPLC Column, 2 μm particle size, L × I.D. 10 cm × 2.1 mm