Department of Chemistry and Biochemistry, University of Oklahoma, United States.
Department of Chemistry and Biochemistry, University of Oklahoma, United States.
Talanta. 2018 May 1;181:416-421. doi: 10.1016/j.talanta.2018.01.045. Epub 2018 Feb 3.
In recent years, much research has gone into developing online comprehensive two-dimensional liquid chromatographic systems allowing for high peak capacities in comparable separation times to that of one-dimensional liquid chromatographic systems. However, the speed requirements in the second dimension (2nd-D) still remain one challenge for complex biological samples due to the current configuration of two column/two detector systems. Utilization of multiple 2nd-D columns can mitigate this challenge. To adapt this approach, we need a multiple channel detector. Here we develop a versatile multichannel ultraviolet (UV) light absorbance detector that is capable of simultaneously monitoring separations in 12 columns. The detector consists of a deuterium lighthouse, a flow cell assembly (a 13-channel flow cell fitted with a 13-photodiode-detection system), and a data acquisition and monitoring terminal. Through the use of a custom high optical quality furcated fiber to improve light transmission, precise machining of a flow cell to reduce background stray light through precision alignment, and sensitive electronic circuitry to reduce electronic noise through an active low pass filter, the background noise level is measured in the tens of µAU. We obtain a linear dynamic range of close to three orders of magnitude. Compared to a commercialized multichannel UV light absorbance detector like the Waters 2488 UV/Vis, our device provides an increase in channel detection while residing within the same noise region and linear range.
近年来，人们投入了大量研究来开发在线综合二维液相色谱系统，使在可比的一维液相色谱系统分离时间内实现更高的峰容量。然而，由于目前的两柱/两检测器系统配置，二维（2nd-D）的速度要求仍然是复杂生物样品面临的一个挑战。利用多个 2nd-D 柱可以缓解这一挑战。为了适应这种方法，我们需要一个多通道检测器。在这里，我们开发了一种通用的多通道紫外（UV）光吸收检测器，能够同时监测 12 根柱子的分离情况。该检测器由氘灯、流池组件（一个 13 通道流池，配备有 13 个光电二极管检测系统）和数据采集和监测终端组成。通过使用定制的高光质量分叉光纤来提高光传输，通过精密加工流池来通过精密对准减少背景杂散光，以及通过有源低通滤波器减少电子噪声的灵敏电子电路，背景噪声水平在数十 µAU 范围内测量。我们获得了接近三个数量级的线性动态范围。与像 Waters 2488 UV/Vis 这样商业化的多通道紫外光吸收检测器相比，我们的设备在相同的噪声区域和线性范围内提供了通道检测的增加。
