Highly efficient separations on 5 μm internal diameter open tubular capillaries coated with thick polyacrylate stationary phases

Abstract

Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. SummaryFused silica capillaries with an internal diameter of 5 gm were coated with polyacrylate films containing either alkyl or ether functionalities. Polymer networks Were created by in situ photopolymerization of acrylic monomers. Capillaries with phase ratios up to 1.3, having excellent separation efficiencies, could be prepared. The performance of these capillaries was demonstrated by the separation of various solute mixtures. Nineteen phenylthiohydantoin (PTH) amino acid derivatives could be separated in less then 10 minutes When using UV detection. Laser Induced Fluorescence detection was used for the separation of polycyclic aromatic hydrocarbons, dansyl (Dns)'derivatized amino acids and o-phthalaldehyde (OPA) derivatized aliphatic amines which could be separated with approximately 310,000 plates in less than 3.5 minutes corresponding to around 1500 plates per second.

A weak cation-exchange phase for the separation of biogenic amines by open tubular liquid chromatography

“…The plate heights of the test solutes on the SiA-AA stationary phase are high compared to previously found values in polyacrylate coated open tubular columns [8].…”

“…Comparing plate heights observed here (120-150 gm) and in the study [8] at the same linear velocity of 10 mm s -1 (12-25 ~tm) a loss in efficiency of nearly a factor 10 is observed. The favourable H-values in [8] were obtained exclusively with swollen stationary phases.…”

“…An OT-LC separation procedure for these compounds could be of considerable interest, because the extremely small sample size needed is often of great importance in biological studies [12][13][14]. In RP OT-LC, using polyacrylate stationary phases, these amines could only be separated in combination with pre-column derivatization [8]. The use of a cation-exchange layer in OT-LC has been demonstrated before by Mtiller et al [15,16].…”

“…capillaries with sufficient sample capacity necessary to avoid column overloading. The last couple of years we reported on the results of an in situ photopolymerization technique to create polymeric acrylate stationary phases in fused silica capillaries [3,[7][8][9]. This technique is different from other coating techniques in that the polymer is formed inside the capillary.…”

“…capillaries in the past [3,[7][8][9], in this study we used laser induced fluorescence (LIF) detection to increase the detectability of the solutes. Native fluorescence of the biogenic amines was measured after excitation with 257 nm radiation from a frequency doubled argon ion laser.…”