Cullison J K, Waraska J, Buttaro D J, Acworth I N, Bowers M L
ESA, Chelmsford, MA 01824, USA.
J Pharm Biomed Anal. 1999 Feb;19(1-2):253-9. doi: 10.1016/s0731-7085(98)00136-8.
Two simple modifications to a commercially available thin layer electrochemical detector cell permitted the attainment of ultra-low detection levels of two neurotransmitter catecholamines. An ESA model 5041 analytical cell was modified with a glassy carbon embedded ceramic composite electrode to allow the use of a thin 12 microm gasket. Also a capillary HPLC column was connected directly to the detector cell using a 30 microm i.d. fused silica capillary. These modifications permitted the extensive redox cycling of the electrochemically reversible catecholamines. The ensuing amplified analytical signal allowed the detector cell to achieve efficiencies of 1300%. This resulted in a mass limit of detection of 4 fg and a concentration limit of detection of 116 pM for dopamine with an S/N of 3.
对市售薄层电化学检测池进行的两项简单改进，使得能够实现两种神经递质儿茶酚胺的超低检测水平。使用嵌入玻璃碳的陶瓷复合电极对ESA 5041型分析池进行了改进，以允许使用厚度为12微米的垫片。此外，使用内径为30微米的熔融石英毛细管将毛细管高效液相色谱柱直接连接到检测池。这些改进使得电化学可逆儿茶酚胺能够进行广泛的氧化还原循环。由此产生的放大分析信号使检测池的效率达到1300%。这导致多巴胺的质量检测限为4飞克，浓度检测限为116皮摩尔，信噪比为3。
