Xu Zhang-Run, Lan Yue, Fan Xiao-Feng, Li Qi
Research Center for Analytical Sciences, Northeastern University, Shenyang 110004, China.
Talanta. 2009 Apr 30;78(2):448-52. doi: 10.1016/j.talanta.2008.11.034. Epub 2008 Dec 3.
An improved automated continuous sample introduction system for microfluidic capillary electrophoresis (CE) is described. A sample plate was designed into gear-shaped and was fixed onto the shaft of a step motor. Twenty slotted reservoirs for containing samples and working electrolytes were fabricated on the "gear tooth" of the plate. A single 7.5-cm long Teflon AF-coated silica capillary serves as separation channel, sampling probe, as well as liquid-core waveguide (LCW) for light transmission. Platinum layer deposited on the capillary tip serves as the electrode. Automated continuous sample introduction was achieved by scanning the capillary tip through the slots of reservoirs. The sample was introduced into capillary and separated immediately in the capillary with only about 2-nL gross sample consumption. The laser-induced fluorescence (LIF) method with LCW technique was used for detecting fluorescein isothiocyanate (FITC)-labeled amino acids. With electric-field strength of 320 V/cm for injection and separation, and 1.0-s sample injection time, a mixture of FITC-labeled arginine and leucine was separated with a throughput of 60/h and a carryover of 2.7%.
描述了一种用于微流控毛细管电泳（CE）的改进型自动连续进样系统。设计了一个齿轮形的样品盘，并将其固定在步进电机的轴上。在样品盘的“齿”上制作了20个用于容纳样品和工作电解质的带槽储液器。一根7.5厘米长的涂有聚四氟乙烯AF的石英毛细管用作分离通道、进样探针以及用于光传输的液芯波导（LCW）。沉积在毛细管尖端的铂层用作电极。通过将毛细管尖端扫描通过储液器的槽来实现自动连续进样。样品被引入毛细管并在毛细管中立即分离，总样品消耗量仅约2纳升。采用液芯波导技术的激光诱导荧光（LIF）方法用于检测异硫氰酸荧光素（FITC）标记的氨基酸。在320 V/cm的电场强度下进行进样和分离，进样时间为1.0秒，FITC标记的精氨酸和亮氨酸混合物的分离通量为每小时60次，残留率为2.7%。
