OPTICAL IMPROVEMENTS OF A Z-SHAPED CELL FOR HIGH-SENSITIVITY UV ABSORBENCY DETECTION IN CAPILLARY ELECTROPHORESIS

被引：112

作者：

MORING, SE ^{[1
]}

REEL, RT ^{[1
]}

VANSOEST, REJ ^{[1
]}

机构：

[1] LC PACKINGS,1057 HM AMSTERDAM,NETHERLANDS

来源：

ANALYTICAL CHEMISTRY | 1993年 / 65卷 / 23期

关键词：

D O I：

10.1021/ac00071a020

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Absorbance detection in capillary electrophoresis (CE) offers excellent mass sensitivity but relatively poor concentration sensitivity. This dichotomy arises from the short optical path lengths found in current detector designs. Minimum detectable concentrations range from 10(-5) to 10(-7) M. The theoretical and physical design aspects affecting signal, noise, and optical transmission of various commercial (CE) detector cells are discussed. A new Z-shaped cell is described which uses a quartz ball lens to optimize light throughput in a 3-mm capillary section. The optical enhancement of the cell provides more than 1 order of magnitude improvement in the signal-to-noise ratio (MDC to 10(-8) M) over that of a conventional cell design with sapphire ball optics. The effect of the increase in cell path length and volume is evaluated for electrophoretic efficiency and resolution. For peak efficiencies up to 200 000 plates, extention of overall path length from 0.075 to 3 mm results in less than 14% loss in efficiency. The new cell design also provides an improvement of linear dynamic range from similar to 3.5 orders of magnitude with a conventional cell to more than 4 orders of magnitude.

引用

页码：3454 / 3459

页数：6

共 8 条

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