https://phys.org/news/2018-07-high-precision-on-site-analysis-precious-metals.html > Suman Barua, Ismail M.M. Rahman, Hiroshi Hasegawa and colleagues from Kanazawa University and Fukushima University have accompished this, reporting the first application of LEP-OES in combination with a solid-phase extraction (SPE) system (which is used as the pre-treatment step to eliminate the competing ions and to enrich the noble metals) for rapid, on-site simultaneous detection of gold, palladium and platinum. The SPE parameters were optimized to maximize retention and recovery of the precious metals; and the LEP-OES parameters were optimized to maximize the emission peaks for the individual elements. The method was tested both on certified reference material for wastewater and on real aqueous waste samples, from which more than 95 percent of the precious metals were recovered. The high-precision on-site measurements could be performed in less than 15 minutes, opening the way to practical analysis of the precious metal content of wastewater. > More information: Suman Barua et al, On-site analysis of gold, palladium, or platinum in acidic aqueous matrix using liquid electrode plasma-optical emission spectrometry combined with ion-selective preconcentration, Sensors and Actuators B: Chemical (2018). DOI: 10.1016/j.snb.2018.05.132