School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China.
School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China.
Anal Chim Acta. 2021 May 15;1159:338427. doi: 10.1016/j.aca.2021.338427. Epub 2021 Mar 19.
In this work, for the first time, a 3D printed two-in-one on-capillary detector, combining contactless conductometric detection (CD) and photometric detection (PD), is fabricated for capillary electrophoresis (CE). The CD Faraday shield (FS) is printed using electrically conductive composite polylactic acid (PLA) to minimize the stray capacitance. Non-conductive PLA is also used to print the insulator of FS to prevent the electrical conduction with two stainless steel electrodes. A novel collimator, consisting of two partially aligned pinholes, is printed by conductive material to collimate the light-emitting diode beam. The CD detection has a signal-to-noise ratio of 1092 ± 2 for 200 μM potassium on a 25 μm id capillary. The PD detection shows excellent linearity with stray light down to 8% and an effective path length at 73% of a 75 μm id capillary. The analytical performance is demonstrated by CE separation and detection of cations. PD shows limits of detection (LODs) of 1.3, 0.9, and 1.7 μM for cobalt, copper and zinc, which are complexed with 4-(2-Pyridylazo) resorcinol, while CD shows LODs of 1.2, 1.4, 21 and 2.6 μM for potassium, sodium, cobalt and zinc, respectively.
在这项工作中，首次为毛细管电泳（CE）制造了一种 3D 打印的一体式在线检测器，结合了非接触电导检测（CD）和光度检测（PD）。CD 法拉第屏蔽（FS）采用导电复合聚乳酸（PLA）打印，以最小化杂散电容。非导电 PLA 也用于打印 FS 的绝缘体，以防止与两个不锈钢电极的电传导。一个由两个部分对齐的小孔组成的新型准直器由导电材料打印，以准直发光二极管光束。在 25 µm id 毛细管上，200 µM 钾的 CD 检测具有 1092 ± 2 的信噪比。PD 检测具有出色的线性度，杂散光低至 8%，有效路径长度为 75 µm id 毛细管的 73%。通过 CE 分离和检测阳离子来证明分析性能。PD 对与 4-(2-吡啶偶氮)间苯二酚络合的钴、铜和锌的检测限（LOD）分别为 1.3、0.9 和 1.7 μM，而 CD 对钾、钠、钴和锌的 LOD 分别为 1.2、1.4、21 和 2.6 μM。
