毛細管電泳訊號之時間效應初探

Abstract

對於流動型分析儀器的訊號，最近有文獻提出了所謂“時間效應”的假說。本研究之目的在於探討毛細管電泳訊號，是否有時間效應的存在。 所謂時間效應是指樣品在管路裡流動時，由於在管中產生的分散現象，會導致樣品在通過偵測器之時，樣品的分佈會因流動而改變，因此所測得樣品之訊號和實際樣品之分佈並不相同。 我們設計了一個多通道的偵測器，可以記錄樣品在毛細管中和時間相關的樣品分佈函數（時圖），和以空間相關的樣品分佈函數（空圖）。由於儀器之偵測靈敏度尚無法提供良好的訊號，我們以目前最好的訊號，來探討毛細管電泳訊號是否有時間效應的存在。結果發現，相同樣品之訊號，其波峰之空圖和時圖都同時會呈現拖尾(tailing)或是趨前(fronting)，因此毛細管電泳之訊號，並無明顯的時間效應存在。

Signals of flowing type analytical instruments are subjected to a so-called “temporal effect” that was proposed recently. This study tries to examine whether the temporal effect exists in capillary electrophoresis.

The temporal effect is said to occur while sample molecules are passing a fixed-position detector. Since the sample dispersion keeps changing during the monitoring, the signal (sample distribution) recorded should be different from that of the true sample distribution in the flow.

We designed a multi-channel detector that enables recording of sample profiles as a function of time (temporal profile) and as a function of longitudinal position (spatial profile). Since the current system was unable to provide decent signals, we used the best data at the present time to examine the temporal effect. As a result, both of the temporal and spatial profiles showed tailing and fronting for signals of the same samples. No significant temporal effect was observed in capillary electrophoresis.