PDF 269.pdf.pdf | Request a copy Full text restricted Available under University of Tasmania Standard License.

Abstract

The optical characteristics of on-capillary photometric detectors for capillary electrophoresis were evaluated and five commercial detectors were compared. Plots of sensitivity (absorbance/concentration) versus absorbance obtained with a suitable testing solution yield both the linear range and the effective path length of the detector. The detector linearity is a crucial parameter when using absorbing electrolytes, such as for indirect photometric detection, and especially for highly absorbing electrolyte probe ions. The upper limits of the linear ranges (determined as 5% decline in sensitivity) for five commercial detectors ranged from 0.175 to 1.2 AU. The effective pathlength reflects the quality of the optical design of the detector and is equal to the capillary internal diameter only for a light beam passing exactly through the capillary centre, but becomes progressively shorter for imperfect optical designs. The determined effective pathlength for the five investigated detectors ranged from 49.7 to 64.6 μm for a 75 μm I.D. capillary.

Item Type:	Article
Authors/Creators:	Johns, CA and Macka, M and Haddad, PR and King, M and Paull, B
Keywords:	Detection, electrophoresis; Photometric detection; Indirect detection; Instrumentation
Journal or Publication Title:	Journal of Chromatography A
ISSN:	0021-9673
DOI / ID Number:	10.1016/S0021-9673(01)01095-0
Additional Information:	The definitive version is available at http://www.sciencedirect.com
Item Statistics:	View statistics for this item

Actions (login required)

Item Control Page