Development of an amperometric detector for packed capillary column supercritical fluid chromatography.
Development of an amperometric detector for packed capillary column supercritical fluid chromatography.
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开发用于填充毛细管柱超临界流体色谱的电流检测器。
DOI：
10.1021/ac960669h
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发表时间：
1997
影响因子：
7.4
通讯作者：
Leif Nyholm
中科院分区：
文献类型：
--
作者：
S. Wallenborg;K. Markides;Leif Nyholm
在裸铂微电极的安培检测被证明是兼容的压力程序化填充毛细管柱超临界流体色谱（SFC）使用二氧化碳改性与低至1%的乙腈。因此，在改性二氧化碳中的安培检测是可能的，而不添加盐，否则盐可能限制色谱系统的稳定性。检测，这可以是基于氧化或还原，也是兼容的使用甲醇作为唯一的改性剂。在恒定压力和压力程序条件下分离后，可以检测到皮克量的二茂铁。二茂铁的检测限，在200个大气压的恒定压力下，被发现是约20 pg。观察到的电流检测器的响应增加与减少移动的相密度和增加量的添加改性剂。分析物进样量增加导致峰拖尾增加，最可能是由于氧化产物在移动的相中的溶解度有限。然而，这种效应的影响是小的毛细管柱SFC中的分析物的相关量。
Amperometric detection at a naked platinum microelectrode is shown to be compatible with pressure-programmed packed capillary column supercritical fluid chromatography (SFC) using carbon dioxide modified with as little as 1% acetonitrile. Amperometric detection in modified carbon dioxide is, hence, possible without addition of salts, which otherwise may limit the stability of the chromatographic system. The detection, which can been based on either oxidations or reductions, is also compatible with the use of methanol as a sole modifier. Picogram amounts of ferrocene could be detected after separations both at a constant pressure and under pressure-programmed conditions. The detection limit for ferrocene, at a constant pressure of 200 atm, was found to be approximately 20 pg. The response of the amperometric detector was observed to increase with decreased mobile phase density and increased amount of added modifier. The injection of increasing amounts of analytes resulted in increased peak tailing, most likely due to the limited solubility of the oxidation products in the mobile phase. The influence of this effect was, however, small for the amounts of analytes relevent in capillary column SFC.