Development of a heavy metal sensing boat for automatic analysis in natural waters utilizing anodic stripping voltammetry

Altres ajuts: CERCA Programme/Generalitat de CatalunyaDetermination of the levels of heavy metal ions would support assessment of sources and pathways of water pollution. However, traditional spatial assessment by manual sampling and off-site detection in the laboratory is expensive and time-consuming and requires trained personnel. Aiming to fill the gap between on-site automatic approaches and laboratory techniques, we developed an autonomous sensing boat for on-site heavy metal detection using square-wave anodic stripping voltammetry. A fluidic sensing system was developed to integrate into the boat as the critical sensing component and could detect ≤1 μg/L Pb, ≤6 μg/L Cu, and ≤71 μg/L Cd simultaneously in the laboratory. Once its integration was completed, the autonomous sensing boat was tested in the field, demonstrating its ability to distinguish the highest concentration of Pb in an effluent of a galena-enriched mine compared to those at other sites in the stream (Osor Stream, Girona, Spain)

Evaluation of voltammetric method for the determination of electrodeposited copper in citrate medium validated by ICP-OES

Copper (Cu) is a toxic pollutant and its presence in wastewater, even at low concentrations, can have a significant environmental impact. In this work, a method for the determination of Cu was developed using a voltammetric technique involving a platinum electrode in citrate medium. Cu at a ppb level was determined by both chronoamperometry (CA) and anodic linear scanning voltammetry (ALSV), and the results were compared to those from inductively coupled plasma optical emission spectroscopy (ICP-OES). The results obtained were similar, having a deviation of 2.56%. The least squares method was used to evaluate the correlation between the ALSV and ICP-OES results. Statistical analyses showed a 95% confidence interval.Keywords: Anodic linear scanning voltammetry, chronoamperometry, copper

DEP-On-Go for Simultaneous Sensing of Multiple Heavy Metals Pollutants in Environmental Samples

We describe a simple and affordable “Disposable electrode printed (DEP)-On-Go” sensing platform for the rapid on-site monitoring of trace heavy metal pollutants in environmental samples for early warning by developing a mobile electrochemical device composed of palm-sized potentiostat and disposable unmodified screen-printed electrode chips. We present the analytical performance of our device for the sensitive detection of major heavy metal ions, namely, mercury, cadmium, lead, arsenic, zinc, and copper with detection limits of 1.5, 2.6, 4.0, 5.0, 14.4, and, 15.5 μg·L−1, respectively. Importantly, the utility of this device is extended to detect multiple heavy metals simultaneously with well-defined voltammograms and similar sensitivity. Finally, “DEP-On-Go” was successfully applied to detect heavy metals in real environmental samples from groundwater, tap water, house dust, soil, and industry-processed rice and noodle foods. We evaluated the efficiency of this system with a linear correlation through inductively coupled plasma mass spectrometry, and the results suggested that this system can be reliable for on-site screening purposes. On-field applications using real samples of groundwater for drinking in the northern parts of India support the easy-to-detect, low-cost (<1 USD), rapid (within 5 min), and reliable detection limit (ppb levels) performance of our device for the on-site detection and monitoring of multiple heavy metals in resource-limited settings