Polarography, advanced pulse

Why did dc polarography rapidly disappear from analytical laboratories in the mid-1950 s The main application of dc polarography in analysis was to heavy metal cation analysis and the detection limit here is about 10 mol dm - (ca 6 ppm for copper). In the mid 1950 s atomic absorption spectroscopy (AAS) became available and was routinely used to analyse for heavy metal cations at <1 ppm. Atomic absorption spectroscopy, although more expensive in initial costs, is an easier technique to use than polarography. Atomic absorption spectroscopy became rapidly established as the method of choice and has remained so until the present day. It is only in recent years that advanced forms of polarography using pulse techniques have begun to become competitive with AAS (see Section 3.0 and 4.0). 

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