方波激发非接触式电导检测器信噪比的影响因素研究  

Factors effecting on signal-to-noise ratio of square wave excitation contactless conductivity detection

作　　者：张水锋[1] 王立世[1] 党志[1] 黄新建[1] 刘笑笑[1] 肖明威[1] 

机构地区：[1]华南理工大学化学科学学院,广州510640

出　　处：《分析试验室》2008年第2期10-14,共5页Chinese Journal of Analysis Laboratory

基　　金：国家自然基金(20475018);广东省自然科学基金(07006544)项目资助

摘　　要：研制了用于毛细管电泳的方波激发非接触式电导检测器(CCD)并详细考查了对检测器信噪比影响较大的几个重要因素,包括激发频率和运算放大器、基线分压电路和A/D转换器、数字低通滤波;以及常见缓冲体系2-(N-吗啡啉)-乙磺酸/组氨酸(MES/His)体系中电解质浓度,添加剂十六烷基三甲基溴化铵(CTAB)对金属离子的检出信号的影响。所得的结果对于该类检测器的设计和优化具有参考价值。A novel square wave excitation contactless conductivity detection was presented, and some significant factors effecting on the signal-to-noise （S/N） ratio of the detector were examined in detail. The assessments of S/N ratios were carried out, including the optimization of the excitation frequency of the square wave and the performance of the operational amplifier, both the parameters of the background baseline voltage-limited resistance and the A/D converter, the digital low-pass filtering parameters, as well as the concentration of the common running buffer, 2-（N-morpholino） ethanesulfonic acid/L-Hisdine （MES/His） and the electroosmosis flow modified reagent, e. g. cetyhrimethylammonium bromide （CTMAB）. The obtained results are significant references for optimization of the contactless conductivity detector.

关 键 词：非接触式电导检测器 方波 毛细管电泳 信噪比 金属离子 

分 类 号：O557.1[理学—热学与物质分子运动论]