SOME SIGNAL CHARACTERISTICS IN DIRECT SAMPLE INSERTION-INDUCTIVELY COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

Direct sample insertion (DSI) is a particularly attractive method for sample introduction for inductively coupled plasma-atomic emission spectrometry (ICP-AES). In this approach a sample is placed into or onto a probe with subsequent introduction of the sample carrying probe, via the central tube of the torch, into the plasma. A generic diagram of a DSI device for ICP-AES is shown. The advantages offered by a DSI device for ICP-AES include 100% sample introduction efficiency and an inherent ability to handle μL volumes of liquid and mg quantities of powdered/solid samples with little or no sample pretreatment. In addition, with a DSI device it is possible to implement in situ sample treatment under the plasma, thereby making use of the temperature gradient in the central channel of the ICP torch.