Disposable sputtered-bismuth screen-printed sensors for voltammetric monitoring of cadmium and lead in atmospheric particulate matter samples

We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and advantageous alternative for reliable and convenient monitoring of Cd and Pb in atmospheric particulate matter (PM10 fraction) by anodic stripping voltammetry after acid digestion. After a detailed exploration of surface composition and depth profiles of the BispSPE by SEM, EDX, XPS and EIS, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring Cd and Pb with detection limits of 11.8 ng mL(-1) and 6.1 ng mL(-1) respectively. These detection limits are useful for pollution monitoring of these elements in ambient air under the requirements of international health and environmental protection standards. The accuracy of the method was assessed by voltammetric measurements of Cd and Pb in ERM (R)-CZ120 Fine dust (PM10-like) and ERM (R) 1648a Urban Particulate Matter certified reference materials. The applicability of the method to Cd and Pb determination in real samples was demonstrated by analysis of PM10 samples from the air quality network in Extremadura, with a good correlation respect to the standard ICP-MS methodology. Our work constitutes the first reference about the use of disposable sensors based on BispSPE for the determination of heavy metals in atmospheric particulate matter samples.