Modified graphite/graphene dot microsensors for the assay of trace amounts of lead and cadmium in water catchments areas using differential pulse anodic stripping voltammetry

Abstract

In this study, dot microsensors based on graphite/graphene paste modified with iron (II) phthalocyanine, nickel (II) phthalocyanine and 5,10,15,20-tetra(4pyridyl)21H, 23H porphine chloride tetrakis(methochloride) manganese(III) were used for the determination of trace amounts of lead and cadmium from various water catchments areas using differential pulse anodic stripping voltammetry. The response of the proposed dot microsensors were sensitive enough to detect very low levels of both metals ions in drinking water resources to take corrective action for the supply of safe and suitable drinking water. The lowest limits of quantification for lead is 0.00207 µg L −1 and for cadmium 5.6 µg L −1 , with a correlation coefficient (R 2 ) between 0.9951 and 0.9981 for lead, and between 0.9951 and 0.9984 for cadmium. The recovery of Pb(II) and Cd(II) in water samples were higher than 93.06 % with RSD(%) values lower than 0.29%. These results of the proposed dot microsensors compared favorably with the results from a standard ISO certified method.

Development of coal fly ash modified graphite-polyurethane composite electrodes for the determination of Cd(II) in batteries and water

“…5f) was obtained between 2.0 x 10 − 7 and 1.0 x 10 6 mol L 1 , with an LOD of 6.61 x 10 − 8 mol L − 1 and R = 0.9989, for n = 5. This LOD was comparable to recent studies of other electrode compositions 11,21 , but lower than that observed for some more expensive or non-usual materials [18][19][20][21][22] . However, GPUE-FA has the advantage of being composed of inexpensive and recycled materials, making it more nancially and environmentally friendly.…”

“…In industry, cadmium is used in conjunction with nickel in rechargeable batteries, in pigments, deposited on various metals due to its resistance to corrosion, in alloys with other metals, and as impurity in the extraction of zinc 17 . There are many papers describing the use of different electrodes for the determination of Cd(II) in water 18,19 , the simultaneous determination of Cd(II) and Pb(II) in water [20][21][22] , herbal food supplements 23 , decorative materials 24 , hair 25 , bivalve mollusks 26 and paint 27 , among others. Other examples describe the simultaneous determination of Cd(II), Pb(II) and Cu(II) using modi ed glassy carbon in water 28 and parts of cigarettes 29 .…”

Azaporphyrins Embedded on Carbon-Based Nanomaterials for Potential Use in Electrochemical Sensing—A Review

“…Recently, some new electrochemical methods have been developed including glassy carbon electrodes with adsorbed nickel oxide. However, in 2019, Arnold-Tatu et al and van Staden et al published their work about utilization of unsubstituted iron(II) and nickel(II) phthalocyanines deposited on reduced graphene oxide and graphene paste, respectively [77,78]. The obtained modified electrodes were assessed in determination of lead and cadmium ions in water samples by using the coordination abilities of porphyrinoids.…”