Advantages and restrictions of glow-discharge sampling

Glow-discharge sampling provides a number of advantages that can be summarized as follows  

It affords direct analysis of both conducting and non-conducting samples (the latter requires using an rf source or mixing with a conductive matrix if a dc source is employed)  

Matrix effects are low and can be minimized using a pulsed source and gated monitoring  

Limits of detection in the parts-per-billion range or even lower are typically obtained that can be improved with the aid of auxiliary means (e.g. laser or MIP assistance) Sensitivity is relatively uniform among elements  

Spectra are much simpler than their optical emission counterparts  

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