Irish Separation Science Cluster, Dublin City University, Glasnevin, Dublin 9, Ireland.
Anal Chem. 2012 Apr 3;84(7):3465-72. doi: 10.1021/ac203432p. Epub 2012 Mar 16.
An automated column fabrication technique that is based on a ultraviolet (UV) light-emitting diode (LED) array oven, and provides precisely controlled "in-capillary" ultraviolet (UV) initiated polymerization at 365 nm, is presented for the production of open tubular monolithic porous polymer layer capillary (monoPLOT) columns of varying length, inner diameter (ID), and porous layer thickness. The developed approach allows the preparation of columns of varying length, because of an automated capillary delivery approach, with precisely controlled and uniform layer thickness and monolith morphology, from controlled UV power and exposure time. The relationships between direct exposure times, intensity, and layer thickness were determined, as were the effects of capillary delivery rate (indirect exposure rate), and multiple exposures on the layer thickness and axial distribution. Layer thickness measurements were taken by scanning electron microscopy (SEM), with the longitudinal homogeneity of the stationary phase confirmed using scanning capacitively coupled contactless conductivity detection (sC(4)D). The new automated UV polymerization technique presented in this work allows the fabrication of monoPLOT columns with a very high column-to-column production reproducibility, displaying a longitudinal phase thickness variation within ±0.8% RSD (relative standard deviation).
本文介绍了一种基于紫外发光二极管（UV LED）阵列烤箱的自动化柱制备技术，可在 365nm 下精确控制“管内”紫外（UV）引发聚合，用于制备不同长度、内径（ID）和多孔层厚度的开放式整体多孔聚合物层毛细管（monoPLOT）柱。该方法通过自动化的毛细管输送方法，可制备不同长度的柱子，因为直接暴露时间、强度和层厚度具有精确的控制和均匀的层厚度和整体形态，这是由受控的 UV 功率和暴露时间决定的。还确定了直接暴露时间、强度和层厚度之间的关系，以及毛细管输送速率（间接暴露速率）和多次暴露对层厚度和轴向分布的影响。通过扫描电子显微镜（SEM）测量层厚度，使用扫描电容耦合非接触式电导检测（sC（4）D）确认固定相的纵向均一性。本工作中提出的新型自动化 UV 聚合技术允许用非常高的柱间重现性制备 monoPLOT 柱，显示出在±0.8%RSD（相对标准偏差）范围内的纵向相厚度变化。
