Nebulizers, Use of Internal Standard and Postcolumn Dilution

INTERFACING NEBULIZERS, USE OF INTERNAL STANDARD AND POSTCOLUMN DILUTION 

The combination of separation techniques on-line with element selective detection methods is resulting in hyphenated systems. These on-line systems have many advantages, especially in routine applications, due to easier operation, higher sample throughput with faster results of better quality than off-line modules, and the risk of contaminations or losses is reduced. 

However, technically, an interface must be available that fulfills the specific requirements of the separation and detection system with respect 

The sample introduction from an LC column to ICP-MS is performed by a nebulizer. The usual nebulizers are pneumatic nebulizers, such as Meinhard, crossflow, or microconcentric nebulizers (MCNs). Additionally, there is the ultrasonic nebulizer (USN), the direct-injection nebulizer (DIN), and the hydraulic high-pressure nebulizer (HHPN). The nebuli-zation efficiency depends on nebulizer type and is typically low for Meinhard and crossflow nebulizers (only around 1—5 %, [23]), whereas it is high for the DIN and USN. 

Much effort has been devoted to interfacing CE with ICP mass spectrometry. CE-ICP-MS provides detection limits in the low pg/l range and the capability for multielement monitoring [11]. AU buffers and modifiers are tolerated by ICP-MS due to the extremely low flow rate inside the capillary of only a few nl/min. Plasma stability remains 

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