Voltammetric Determination of Copper by Biosorption‐based Mesorhizobium Opportonistum Modified Microbial Biosensor

Abstract

In this study, Cu (II) was determined with a carbon paste electrode modified with Mesorhizobium opportonistum bacteria species used for the first time in the production of a microbial biosensor (MOMB). Cu (II) ions were first accumulated on an electrode surface via open circuit, then electrochemical determination was conducted with cyclic and differential pulse cathodic stripping voltammetry techniques. Experimental conditions such as pH, scan rate etc. were optimized. The MOMB exhibited linearity in the range of 5.0 × 10 À 8 M to 2.0 × 10 À 6 M for Cu (II) (correlation coefficients: 0.9914) with detection limit (LOD) of 2.0 × 10 À 8 M, a limit of quantification (LOQ) 6.64 × 10 À 8 M and a detection sensitivity (10.34 μA/μM), for Cu (II). The electrode-to electrode reproducibility of the MOMB was found to be 2.41 % (n = 6) coefficient of variation. The MOMB has advantages for Cu (II) determination, including good sensitivity and reproducibility, easy preparation, low cost, applicability to sample and not having a need for additional chemical processes.

Novel Aspects in the Voltametric Determination of Heavy Metals: A Minireview

“…MOMB has advantages for the determination of Cu(II), including good sensitivity and reproducibility, easy preparation, low cost, applicability to the sample, and no need for additional chemical processes. The LOD and LOQ limits were 2.0 × 10 -8 M and 6.64 × 10 -8 M respectively [90]. Another technique utilizing differential pulse anodic stripping voltammetry used a glassy electrode molded with Nafion solution, multiwall carbon nanotubes, and 1-butyl-3-methylimidazole hexafluorophosphate (MWCNTs-BMIMPF6-Naf-GCE).…”