Sensitive Determination of the Diquat Herbicide in Fresh Food Samples on a Highly Boron‐Doped Diamond Electrode

Abstract

The highly boron-doped diamond electrode (HBDD) combined with square wave voltammetry (SWV) was used in the development of an analytical procedure for diquat determination in potato and sugar cane samples and lemon, orange, tangerine and pineapple juices. Preliminary experiments realised in a medium of 0.05 mol L À1 Na 2 B 4 O 7 showed the presence of two voltammetric peaks around À0.6 V and around À1.0 V vs. Ag/AgCl/Cl À 3.0 mol L À1 , where the first peak could be successfully used for analytical proposes due the facility in the electrode surface renovation. After the experimental and voltammetric optimisation, the calculated detection and quantification limits were 1.6 10 À10 mol L À1 and 5.3 10, respectively), which are lower than the maximum residue limit established for fresh food samples by the Brazilian Sanitary Vigilance Agency. The proposed methodology was used to determine diquat residues in potato and sugar cane samples and lemon, orange, tangerine and pineapple juices and the calculated recovery efficiencies indicated that the proposed procedure presents higher robustness, stability and sensitivity, good reproducibility, and is very adequate for diquat determination in complex samples.

Sensitive electrochemical determination of yohimbine in primary bark of natural aphrodisiacs using boron-doped diamond electrode

“…18,19 However, the analytical performance of BDD electrodes is strongly affected by the quantity of doping agent, morphologic factors, the presence of impurities and crystallographic orientation. 20 Besides these aspects, the physical and chemical properties of BDD electrodes are also inuenced by controllable (hydrogen or oxygen) surface termination achieved either by exploitation of oxygen and hydrogen plasmas or by electrochemical pretreatment with highly anodic and cathodic potentials. 21 Our research group has extensively applied BDD electrodes as effective alternatives to traditional electrode materials for the sensitive determination of various biologically active compounds important in the area of environmental, [22][23][24][25] food 26 and drug analysis.…”

Analytical Applications of Electrochemically Pretreated Boron‐Doped Diamond Electrodes

“…Conventionally, in many cases the CPT is preceded by an APT to clean the BDDE surface, oxidizing any strongly adsorbed organic contaminant . For example, the electroanalytical determination of the herbicide picloram was carried out using a CPT‐BDDE, whose pretreatment was always preceded by an APT; the CPT or APT involved polarizations at −2.0 V or +2.0 vs .…”

Electroanalytical determination of the linuron herbicide using a cathodically pretreated boron-doped diamond electrode: comparison with a boron-doped diamond electrode modified with platinum nanoparticles

“…[13][14][15][16] However, there are few studies using a boron-doped diamond electrode (BDDE) for the determination of this kind of analyte. 17 One of the main characteristics of this electrode is low surface adsorption by organic compounds. 18 This quality is very important in pesticide determination since the biggest problem is poisoning of the electrode surface aer a few measurements.…”