Hand-Portable Gradient Capillary Liquid Chromatography Pumping System.
Hand-Portable Gradient Capillary Liquid Chromatography Pumping System.
复制标题
手持式梯度毛细管液相色谱泵系统。
作者：
Soni Sharma;Alex Plistil;Hal E. Barnett;H. Tolley;P. B. Farnsworth;Stanley D. Stearns;Milton L. Lee
在这项工作中，开发了一种新型的无分裂纳米流梯度发生器，集成了一个停止流动的注射器，并使用柱上紫外吸收检测器进行了评估。梯度泵系统由两个由微型步进电机控制的纳米流泵、一个连接在蛇形管上的混合器和一个高压阀组成。该梯度系统重量仅为4公斤（9磅），可产生高达55 MPa （8000 psi）的压力。该系统可以使用24 V直流电池运行，运行需要1.2 a。泵的总容积为74 μL，可进样量为60 nL。该系统在不使用分离器的情况下提供了低至10 nL/min的精确纳米流量，使其成为毛细管柱使用的理想选择。计算出梯度停留体积为1.3 μL，在典型流量为350 nL/min时，产生约4 min的延迟。评估梯度性能的梯度步长精度，在日常实验中获得了良好的再现性（RSD < 1.2%, n = 4）。采用聚乙二醇二丙烯酸酯（PEGDA）整体柱对三组分农药混合物进行了线性梯度重现性测试。运行-运行实验的保留时间重现性很好（RSD < 1.42%, n = 4）。最后，利用纳米流梯度系统对5种酚类化合物进行了较好的分离。
In this work, a novel splitless nanoflow gradient generator integrated with a stop-flow injector was developed and evaluated using an on-column UV-absorption detector. The gradient pumping system consisted of two nanoflow pumps controlled by micro stepper motors, a mixer connected to a serpentine tube, and a high-pressure valve. The gradient system weighed only 4 kg (9 lbs) and could generate up to 55 MPa (8000 psi) pressure. The system could operate using a 24 V DC battery and required 1.2 A for operation. The total volume capacity of the pump was 74 μL, and a sample volume of 60 nL could be injected. The system provided accurate nanoflow rates as low as 10 nL/min without employing a splitter, making it ideal for capillary column use. The gradient dwell volume was calculated to be 1.3 μL, which created a delay of approximately 4 min with a typical flow rate of 350 nL/min. Gradient performance was evaluated for gradient step accuracy, and excellent reproducibility was obtained in day-to-day experiments (RSD < 1.2%, n = 4). Linear gradient reproducibility was tested by separating a three-component pesticide mixture on a poly(ethylene glycol) diacrylate (PEGDA) monolithic column. The retention time reproducibility was very good in run-to-run experiments (RSD < 1.42%, n = 4). Finally, excellent separation of five phenols was demonstrated using the nanoflow gradient system.