Parts per trillion detection of heavy metals in as-is tap water using carbon nanotube microelectrodes

Carbon Nanotube Microelectrode Set: Detection of Biomolecules to Heavy Metals

“…In our most recent study, we reported a microsensor that consisted of six CNT fiber cross sections, where each cross section had a diameter of 70 μm and was employed along with the commercial Ag/AgCl reference electrode and platinum wire as the counter electrode, to detect Pb 2+ . This working electrode had a linear range response of 0.1–50 ppb . On the other hand, in the current study, the working electrode is made up of a single 40 μm fiber cross section, thus limiting the linear range of Pb 2+ detection in tap water to 1–30 ppb.…”

“…This working electrode had a linear range response of 0.1−50 ppb. 101 On the other hand, in the current study, the working electrode is made up of a single 40 μm fiber cross section, thus limiting the linear range of Pb 2+ detection in tap water to 1−30 ppb. Accommodating multiple microelectrodes as working electrodes within the μ-ES resulted is challenging; as a result, a single working electrode is employed, but still the reported μ-ES showed excellent sensitivity.…”

Considerations for new manganese analytical techniques for drinking water quality management

“…The surface of the working electrode is smaller, which reduces the overall current, but the sensitivity is increased due to increased ratio of diffusion layer volume to surface area. Gupta et al (2021) fabricated carbon nanotube microelectrodes with diameters down to ~69 μm. The microelectrodes were tested for heavy metal detection in tap water (e.g., Cu 2+ , Pb 2+ , Cd 2+ ), which was sensitive to parts per trillion sensitivity.…”

Impact of physical and chemical parameters on square wave anodic stripping voltammetry for trace Pb2+ detection in water

“…32 The WQPs of tap water vary with location, season, anthropogenic activity, and source (ground or surface water), 32 affecting the applicability of the SWASV technique for HMI detection. 31 The solubility of Pb 2+ ions increases at lower pH values, as revealed by equilibrium models such as the Pourbaix diagrams of lead with various compounds as well as lead pipe scale and coupon studies. 28,33 As crucial WQPs, water hardness and alkalinity are expressed as mg L −1 CaCO 3 , but they represent various chemical species in water.…”

“…Although the optimal buffer, molarity, and pH have been investigated for a multitude of electrodes, 23 the effects of various WQPs on the SWASV technique for Pb 2+ detection in unaltered drinking water are not well understood. 31 There is a need to understand the impact of these WQPs on the SWASV technique for detecting Pb 2+ without the addition or dilution with supporting electrolyte, representing each WQP from expected concentration ranges reported for real water samples.…”