Detection limit for ions

The lower detection limit for ions M+ or Y is often given as the intersection of the Nernstian region with the limiting potential of equation 9. This value depends on the membrane loading MY(org.) and is given by... 

Detection limits for ions vary with the sensitivity of the detector, with the volume of sample injected, and with the identity, concentration, and pH of the eluent, as well as with chromatographic factors, such as column efficiency and so forth. 

With the use of new monolithic columns with narrow diameters for IC, the detection limits for ions have been decreased even further. The silica gel-based solid in the monolith is functionalised with the ion exchange material and it is highly porous with a high capacity. These columns have low back pressure so high fiow rates, fast separations and well defined peaks mean better sensitivity (sub ppb). 

Koch, W. Liggett, W. "Critical Assessment of Detection Limits for Ion Chromatography" - Chapt. 11 in this volume. 

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