Pretreated Boron-doped Diamond Electrode Research Articles

The cathodically pretreated boron-doped diamond electrode as an environmentally friendly electrochemical tool for the detection and monitoring of mesotrione in food samples

Excessive pesticide use can harm human health, making it essential to develop new techniques to monitor hazardous pesticides in food. Our study focuses on detecting mesotrione (MST) using an unmodified boron-doped diamond (BDD) electrode. This was the first application of cathodically pretreated BDD electrode for the detection of MST, based on its oxidation at a high potential value of +1.4 V. We theoretically examined the oxidation mechanism of MST trough the utilization of density functional theory (DFT) methodology. The utilized DPV method achieved a detection limit of 0.45 μM and showed satisfactory selectivity. The practical application of this method was demonstrated by examining corn-based food products. To ensure practical application of the method, MST was deliberately added to the samples to evaluate the accuracy of the proposed method. The effectiveness of the method was confirmed by using HPLC method. This environmentally-friendly approach can establish a solid foundation for future use in food analysis.

Development of environmentally friendly voltammetric methods for the individual and simultaneous determination of antihypertensives: Validation and application

In this study, voltammetric methods were developed and validated for the individual determination of lisinopril (LSNP) and its association with hydrochlorothiazide (HCTZ) employing a cathodically pretreated boron-doped diamond (CP-BDD) electrode. The studies of the experimental and instrumental parameters that affect the performance of both methods were carefully carried out by optimizing each parameter. The methods were validated by evaluating the figures of merits recommended by the validation guidelines. The method for the individual determination of LSNP presented a linear working range between 9.99 and 196.01 nmol L−1, with a limit of detection of 3.05 nmol L−1 by differential pulse voltammetry in BR buffer solution (pH 2.0). Simultaneous analytical curves over the concentration ranges of 0.40–3.99 and 0.050–1.045 μmol L−1 for HCTZ and LSNP, respectively, were obtained by square-wave voltammetry in Britton-Robinson buffer solution (pH 3.0). The limit of detection values calculated were 0.052 μmol L−1 and 0.020 μmol L−1, respectively for HCTZ and LSNP. The sensitivity observed for individual analytical curves of HCTZ and LSNP was statistically equal to that obtained for the simultaneous analytical curves at the 95 % confidence level. The developed methods were applied to determine these drugs in environmental, biological, and pharmaceutical samples, with satisfactory results. The method's greenness was assessed demonstrating that both validated methods constitute a greener alternative to conventional analytical methods reported in the literature.

Cloud point method applied to the extraction and preconcentration of thiabendazole pesticide from whole grape juice samples and amperometric detection by HPLC.

A cloud point method was developed and applied for the first time to extract and preconcentrate thiabendazole (TBZ) from commercial whole grape juice samples, with determination by high performance liquid chromatography coupled to electrochemical detection (HPLC/EC), using a cathodically pretreated boron-doped diamond electrode (BDD). The best conditions for extraction and preconcentration of TBZ by cloud point extraction (CPE) were performed at pH 6.0, by adding 1 mL of the surfactant Tergitol TMN-6 at 10% (mass-to-mass ratio), without heating (at 27 °C) and ultrasonic stirring time of (20 kHz) for 60 min. The HPLC/EC determination was duly validated in a C8 column, in mobile phase with a 69 : 31 ratio (V/V) of phosphate buffer (pH 7.0):ACN, at a flow rate of 1.2 mL min-1 and electrochemical detection with BDD electrode by applying 1.40 V × Ag/AgCl (3.0 mol L-1). Under these conditions, the procedure showed a preconcentration factor (FC) of 21.7, and limits of detection (LOD) and quantification (LOQ) of 6.64 × 10-9 mol L-1 (or 1.33 μg L-1) and 1.66 × 10-8 mol L-1 (or 3.34 μg L-1), respectively. The method provided a percent recovery of 81% to 98%, with a coefficient of variation between 3% and 15%.

Development of an Electroanalytical Method for Ronidazole Determination in Environmental and Food Matrices Using Boron-Doped Diamond Electrode

A novel electroanalytical approach is presented for the determination of ronidazole in environmental and food matrices by applying a cathodically pretreated boron-doped diamond electrode and the square-wave adsorptive cathodic stripping voltammetry technique. From the studies of cyclic voltammetry to investigate the electroactivity of the ronidazole molecule, the occurrence of an irreversible cathodic process was verified, which was more efficiently detected using the cathodically pretreated boron-doped diamond electrode compared to the anodically pretreated electrode. Still on the electrochemical response of ronidazole, the effects of pH and scan rate were studied and, its apparent diffusion coefficient was determined by chronoamperometry (8.20 × 10−6 cm2 s−1). Under optimal experimental conditions, the analytical curve obtained for ronidazole was linear in two concentration ranges (12.70 to 63.40 µmol L−1 and 76.04 to 126.2 µmol L−1), with a limit of detection of 2.55 µmol L−1. For intra- and inter-day repeatabilities, relative standard deviations of only 2.7 and 3.5% were verified, which demonstrated the stable analytical response of the electrode. Recovery percentages ranging from 96 to 100% were achieved in the analysis of natural water and whole milk samples. Therefore, the proposed electroanalytical method shows satisfactory analytical performance towards ronidazole determination in varied matrice samples.

Ultra-sensitive determination of serotonergic antidepressant vortioxetine in pharmaceutical and blood samples at the boron-doped diamond electrode

In this work, an ultra-sensitive voltammetric method for the determination of serotonergic antidepressant vortioxetine (VTX) was developed using an anodically pretreated boron-doped diamond electrode and square-wave voltammetry (SWV). In this modification-free platform, VTX was irreversibly oxidized at 1.09 V (vs. Ag/AgCl (3.0 mol/L KCl)) in Britton–Robinson buffer solution (pH 4.0). Under optimized instrumental parameters of SWV, the oxidation current of VTX increased linearly in the concentration range of 9.99 – 148 nmol/L, obtaining a limit of detection of 2.35 nmol/L. The method was successfully applied to commercially available Brintellix® tablets, and the results obtained were statistically similar to those obtained by a spectrophotometric method. Additionally, the simultaneous determination of VTX and amiloride was demonstrated and applied in blood rat serum. The method proved not to suffer from matrix interference providing excellent recoveries.

Simultaneous Determination of Uric Acid and Caffeine by Flow Injection Using Multiple-Pulse Amperometry.

The present study reports the development and application of a flow injection analysis (FIA) system for the simultaneous determination of uric acid (UA) and caffeine (CAF) using cathodically pretreated boron-doped diamond electrode (CPT-BDD) and multiple-pulse amperometry (MPA). The electrochemical profiles of UA and CAF were analyzed via cyclic voltammetry in the potential range of 0.20-1.7 V using 0.10 mol L-1 H2SO4 solution as supporting electrolyte. Under optimized conditions, two oxidation peaks at potentials of 0.80 V (UA) and 1.4 V (CAF) were observed; the application of these potentials using multiple-pulse amperometry yielded concentration linear ranges of 5.0 × 10-8-2.2 × 10-5 mol L-1 (UA) and 5.0 × 10-8-1.9 × 10-5 mol L-1 (CAF) and limits of detection of 1.1 × 10-8 and 1.3 × 10-8 mol L-1 for UA and CAF, respectively. The proposed method exhibited good repeatability and stability, and no interference was detected in the electrochemical signals of UA and CAF in the presence of glucose, NaCl, KH2PO4, CaCl2, urea, Pb, Ni, and Cd. The application of the FIA-MPA method for the analysis of environmental samples resulted in recovery rates ranging between 98 and 104%. The results obtained showed that the BDD sensor exhibited a good analytical performance when applied for CAF and UA determination, especially when compared to other sensors reported in the literature.

Improved procedure for square-wave voltammetric sensing of fenhexamid residues on blueberries peel surface at the anodically pretreated boron-doped diamond electrode

BackgroundFungicide fenhexamid (FH) has a high residual concentration on fruits and vegetables, thus, it is of high importance to monitor the level of FH residues on foodstuff samples. So far, the assay of FH residues in selected foodstuff samples has been conducted by electroanalytical methods on sp2 carbon-based electrodes that are well-known to be susceptible to severe fouling of the electrodes surfaces during electrochemical measurements. As an alternative, sp3 carbon-based electrode such as boron-doped diamond (BDD) can be used in the analysis of FH residues retained on the peel surface of foodstuff (blueberries) sample. ResultsIn situ anodic pretreatment of the BDDE surface was found to be the most successful strategy to remediate the passivated BDDE surface by FH oxidation (by)products, and the best validation parameters, i.e., the widest linear range (3.0–100.0 μmol L−1), the highest sensitivity (0.0265 μA L μmol−1) and the lowest limit of detection (0.821 μmol L−1), were achieved on the anodically pretreated BDDE (APT–BDDE) in a Britton-Robinson buffer, pH 2.0, using square-wave voltammetry (SWV). The assay of FH residues retained on blueberries peel surface was performed on the APT–BDDE using SWV, and the obtained concentration of FH residues of 6.152 μmol L−1 (1.859 mg kg−1) was found to be below the maximum residue value fixed for blueberries by the European Union regulations (20 mg kg−1). Significance and noveltyIn this work, a protocol based on a very easy and fast foodstuff sample preparation procedure combined with the straightforward pretreatment approach of the BDDE surface was elaborated for the first time for the monitoring of the level of FH residues retained on the peel surface of blueberries samples. The presented reliable, cost-effective, and easy-to-use protocol could find its application as a rapid screening method for the control of food safety.

An anodically pretreated boron-doped diamond electrode surface for square-wave adsorptive stripping voltammetric quantification of the non-absorbable antibiotic rifaximin in the pharmaceutical formulation

An anodically pretreated boron-doped diamond electrode surface for square-wave adsorptive stripping voltammetric quantification of the non-absorbable antibiotic rifaximin in the pharmaceutical formulation

The First Electroanalytical Study Of Umifenovir (Arbidol) Used As A Potential Antiviral Drug For The Treatment of SARS-CoV-2: A Voltammetric Quantification On The Boron-Doped Diamond Electrode By Using Anionic Surfactant Media

In this work, an electroanalytical procedure for sensing umifenovir (arbidol) by square wave adsorptive stripping voltammetry (SW-AdSV) was developed utilizing an anodically pretreated boron-doped diamond electrode. Measurements of umifenovir using cyclic voltammetry with phosphate buffer solution (PBS, 0.1 M, pH 2.5) revealed irreversible behaviour, adsorption-controlled as well as an ill-defined (+1.13 V, PA1) and a well-defined (+1.47 V, PA2) two oxidation peaks. Umifenovir oxidations depend critically on supporting electrolytes and pH. The second oxidation peak (PA2) current of the umifenovir was enhanced by adding sodium dodecyl sulfate (SDS, anionic surfactant) in the chosen supporting electrolyte. Umifenovir was quantified using its second oxidation peak (PA2) at about +1.39 V. Using the optimized condition, the oxidation peak current of PA2 showed a linear relationship for umifenovir determination in the concentration range from 0.005 to 1.0 μg ml−1 (9.73 × 10−9−1.95 × 10−6 M), with a detection limit of 0.0014 μg ml−1 (2.72 × 10−9 M) in PBS (PH 2.5) with SDS. Finally, the developed approach was successfully utilized to determine umifenovir in the pharmaceutical formulation and urine samples. To the best of our knowledge, this is the first electroanalytical approach for voltammetric sensing of umifenovir.

The first electrochemical evaluation and voltammetric detection of the insecticide emamectin benzoate using an unmodified boron-doped diamond electrode

This study introduces for the first time an electroanalytical investigation and novel voltammetric method for the determination of emamectin benzoate (EB) using a cathodically pretreated boron-doped diamond electrode (CTP-BDDE). The CPT-BDDE electrode exhibited a well-defined irreversible signal at ∼1.35 V (vs. Ag/AgCl) using cyclic voltammetry. Different scan rates (from 10 to 750 mV s−1) suggested that the oxidation of EB on the BDDE surface is a diffusion-controlled process. Using square wave voltammetry, the anodic peak current was linear with EB concentrations from 0.25 mg L-1 to 12.5 mg L-1, with LOD and LOQ found to be 0.079 and 0.263 mg L-1, respectively. The effect of other insecticides used to treat sea lice and inorganic ions found in seawater on the voltammetric detection of EB was negligible. The proposed method was successfully applied to the determination of EB at different concentrations in real sea water samples. To the best of our knowledge, the voltammetric behaviour of EB and the electrochemical method for EB determination is reported for the first time.

Voltammetric determination of anti-malarial drug amodiaquine at a boron-doped diamond electrode surface in an anionic surfactant media

In this study, the electrochemical determination of the amodiaquine (ADQ) drug was evaluated using an electrochemically pretreated boron-doped diamond (BDD) electrode due to the enhanced surface activity. The cyclic voltammogram results of ADQ were given as single reversible and diffusion-controlled peaks at +0.48 V for the oxidation peak and +0.05 V for the reduction peak (vs. Ag/AgCl) in Britton-Robinson (BR) buffer at pH 8.0. The peak potential and current signals of ADQ were evaluated at the surface of the BDD electrode using instrumental parameters to develop a simple method for ADQ detection. Also, the effect of an anionic surfactant, sodium dodecyl sulfate (SDS), on the adsorption applicability of the BDD electrode significantly increased the stripping voltammetric determination of ADQ. Under the optimal conditions chosen and employing square-wave adsorptive stripping voltammetry at the BDD electrode, ADQ was determined at + 0.34 V (vs. Ag/AgCl) at the open-circuit condition in BR buffer at pH 8.0 in the presence of 2·10–4 mol l–1 SDS. Furthermore, analytical parameters showed the linear relationship for ADQ determination in the concentration range of 0.1–20.0 μg ml–1 (2.2·10–7 – 4.3·10–5 mol l–1), with a detection limit of 0.03 μg ml–1 (6.5·10–8 mol l–1). The proposed approach can be applied to determine ADQ in water samples.

Flow Injection Analysis System Coupled to Chronoamperometry and Boron-Doped Diamond Electrode for Determination of Synthetic Hormones 17α-Ethinylestradiol and Cyproterone Acetate

Flow injection analysis with chronoamperometry detection using a cathodically pretreated boron-doped diamond electrode (CPT-BDDE) was employed to develop and optimize a novel method for the determination of the hormones 17-α-ethinylestradiol (EE2) and cyproterone acetate (CPA). The electrochemical properties of EE2 and CPA were evaluated by cyclic voltammetry and oxidation peaks were observed at 0.97 V and 1.60 V in 0.04 mol L−1 Britton-Robinson buffer (pH 2.0). Analytical curves were linear in the concentration range from 0.070 to 10.0 µmol L−1 for EE2 and 1.0 to 80.0 µmol L−1 for CPA with detection limits of 0.023 and 0.23 µmol L−1, respectively. The developed methods presented good precision and accuracy for EE2 and CPA quantification in commercial pharmaceutical samples. The obtained results were satisfactory and consistent compared with a reference high-performance liquid chromatography method at a confidence level of 95%. Furthermore, recovery studies carried out in synthetic urine and lake water show that these methods do not suffer any significant matrix interferences and are potentially applicable for the determination of these hormones in real samples. Thus, the developed procedure for EE2 and CPA determination are simple and fast, with an analytical frequency of ∼83 determinations per hour, and attractive for routine analysis.

First electrochemical study of a potent antifungal drug caspofungin: Application to its enhanced voltammetric sensing based on the performance of boron-doped diamond electrode in CTAB-mediated measurements

This present study describes the first electrochemical investigation of caspofungin, which is a semisynthetic echinocandin class of antifungal drug. For this purpose, an electrochemically pretreated (anodically and subsequently cathodically) boron-doped diamond (BDD) electrode was used. The cyclic voltammetric scans showed a single oxidation step that is irreversible and controlled by a dual mechanism of adsorption and diffusion. For the optimization of experimental conditions, the influence of the electrode pretreatment, pH of the supporting electrolyte, concentration of cationic surfactant cetyltrimethylammonium bromide (CTAB), accumulation variables, and instrumental parameters was examined on the current response of caspofungin. The improved sensitivity of the voltammetric measurements was observed due to the synergistic effect of CTAB on the adsorption capacity of BDD electrode in alkaline pH conditions. Employing square-wave adsorptive stripping voltammetry (using open-circuit accumulation for 60 s), the oxidation signal at around +0.45 V allowed to the determination of caspofungin in Britton-Robinson buffer at pH 11.0 containing 1 × 10−4 M CTAB. The process could be used in the concentration range from 2.06 × 10−7 to 1.03 × 10−5 M (from 0.25 to 12.5 μg mL−1 as acetate salt) with a detection limit of 5.27 × 10−8 M (0.064 μg mL−1 as acetate salt). A technique developed here was used successfully to determine caspofungin concentration in commercial parenteral dosage formulations.

Analytical Methodologies for Determination of Hydroxychloroquine and its Metabolites in Pharmaceutical, Biological and Environmental Samples

Background:Hydroxychloroquine (HCQ) was originally launched as an antimalarial drug, but now it is also used as a slow-acting anti-rheumatic drug. It contains equal proportions of (-)-(R)-hydroxychloroquine and (+)-(S)-hydroxychloroquine.Introduction:Hydroxychloroquine, a synthetic 4-aminoquinoline derivative, possesses antimalarial, anti-rheumatic activity and also exerts beneficial effects on lupus erythematous disease. Substantial levels of three metabolites of HCQ, which are desethylchloroquine (DCQ), bisdesethylhydroxychloroquine (BDCQ), and desethylhydroxychloroquine (DHCQ), have been determined by various analytical techniques from blood and plasma.Methods:Various analytical techniques have been reported for asynchronous and simultaneous estimation of HCQ and their metabolites in pharmaceuticals and biological samples like (serum, whole blood, and urine). The analytical techniques are Square-wave voltammetry employed with the cathodically pretreated boron-doped diamond electrode, fast UHPLC–fluorescent method, UV spectrophotometry, UHPLC-UV analysis, RP-HPLC, mass spectrometry, NMR, and CE.Results:We have complied various analytical methods to detect HCQ with its various metabolites simultaneously or alone in pharmaceutical dosage forms, biological and environmental samples.Conclusion:The authors believe that the above-mentioned studies compiled in this report will give a choice to readers to select the most appropriate and suitable method for the analysis of HCQ. Further, it is also believed that this study will help the researchers to develop a more sensitive, convenient, and rapid method for these based on literature reports.

Square-wave voltammetric sensing of Lawsone (2-hydroxy-1,4-naphthoquinone) based on the enhancement effect of cationic surfactant on anodically pretreated boron-doped diamond electrode.

In this reported work, an anodically pretreated boron-doped diamond (BDD) electrode was used for the inexpensive, simple and quick detection of a natural dye, lawsone. Lawsone had a well-defined, irreversible and diffusion-controlled oxidation peak at approximately +0.19 V in phosphate buffer solution (PBS, 0.1 M, pH 2.5) using cyclic voltammetry (CV). The oxidation peak heights of lawsone were significantly increased in PBS using the cationic surfactant cetyltrimethylammonium bromide (CTAB). Under optimized experimental conditions, the calibration curve was linear over a concentration range of 0.1-5.0 μM with detection limit of 0.029 μM in 0.1 M PBS (pH 2.5) containing 0.1 mM CTAB by using square-wave voltammetry (SWV). To evaluate the practical applicability of the BDD electrode, it was used for the quantification of lawsone in commercial henna, a natural dye made from the leaves of the henna plant.

First electrochemical evaluation of favipiravir used as an antiviral option in the treatment of COVID-19: A study of its enhanced voltammetric determination in cationic surfactant media using a boron-doped diamond electrode

Favipiravir, a promising antiviral agent, is undergoing clinical trials for the potential treatment of the novel coronavirus disease 2019 (COVID-19). This is the first report for the electrochemical activity of favipiravir and its electroanalytical sensing. For this purpose, the effect of cationic surfactant, CTAB was demonstrated on the enhanced accumulation of favipiravir at the surface of cathodically pretreated boron-doped diamond (CPT-BDD) electrode. At first, the electrochemical properties of favipiravir were investigated in the surfactant-free solutions by the means of cyclic voltammetry. The compound presented a single oxidation step which is irreversible and adsorption controlled. A systematic study of various operational conditions, such as electrode pretreatment, pH of the supporting electrolyte, concentration of CTAB, accumulation variables, and instrumental parameters on the adsorptive stripping response, was examined using square-wave voltammetry. An oxidation signal at around +1.21 V in Britton-Robinson buffer at pH 8.0 containing 6 × 10−4 M CTAB allowed to the adsorptive stripping voltammetric determination of favipiravir (after 60 s accumulation step at open-circuit condition). The process could be used in the concentration range with two linear segments of 0.01–0.1 μg mL−1 (6.4 × 10−8-6.4 × 10−7 M) and 0.1–20.0 μg mL−1 (6.4 × 10−7-1.3 × 10−4 M). The limit of detection values were found to be 0.0028 μg mL−1 (1.8 × 10−8 M), and 0.023 μg mL−1 (1.5 × 10−7 M) for the first and second segments of calibration graph, respectively. The feasibility of developed methodology was tested to the analysis of the commercial tablet formulations and model human urine samples.

First report for the electrochemical investigation of a new HIV integrase inhibitor dolutegravir: Its voltammetric determination in tablet dosage forms and human urine using a boron-doped diamond electrode

In this paper, for the first time, the study of electrochemical investigation and voltammetric determination of HIV integrase inhibitor dolutegravir was described. The effect of pretreatment (anodically or cathodically) of boron-doped diamond electrode was investigated in detail on the stripping voltammetric performance for this compound. Dolutegravir presented one or two oxidation peaks within the pH range 2.0–12.0 by using both pretreated electrodes. Employing square-wave stripping mode on the surface of cathodically pretreated boron-doped diamond electrode (after 60 s accumulation at +0.3 V) in Britton-Robinson buffer at pH 10.0, there was a linear dependence of the peak current at +0.79 V (vs. Ag/AgCl, 3 M NaCl) and dolutegravir concentration in the range of 1.0–50.0 μg mL−1 (2.38 × 10−6–1.19 × 10−4 M), with a detection limit of 0.26 μg mL−1 (6.20 × 10−7 M). The applicability of the developed approach for the quantification of dolutegravir was tested in the commercial tablet formulations and model human urine samples.

Sensitive Voltammetric Detection of Chloroquine Drug by Applying a Boron-Doped Diamond Electrode

In this research, a boron-doped diamond (BDD) electrode has been explored to detect the chloroquine drug. The electrochemical performance of BDD electrode towards the irreversible anodic response of chloroquine was investigated by subjecting this electrode to the cathodic (−0.5 A cm−2 by 180 s, generating a predominantly hydrogen-terminated surface) and anodic (+0.5 A cm−2 by 30 s, oxygen-terminated surface) pretreatments. The cathodically pretreated BDD electrode ensured a better-defined anodic peak and higher current intensity. Thus, by applying the cathodically pretreated BDD electrode and square-wave voltammetry (SWV), the analytical curve was linear from 0.01 to 0.25 µmol L−1 (correlation coefficient of 0.994), with sensitivity and limit of detection of 12.2 µA L µmol−1 and 2.0 nmol−1, respectively. This nanomolar limit of detection is the lowest recorded so far with modified and unmodified electrodes.

Voltammetric determination of natamycin using a cathodically pretreated boron-doped diamond electrode in the presence of sodium dodecyl sulfate

The work describes a new electrochemical method of assaying natamycin in pharmaceutical preparations and food products. The proposed procedure involves the use of cathodic-conditioned boron-doped diamond electrode (BDD) and sensitive electrochemical techniques. Well-defined oxidation peaks of natamycin, but no reduction peaks, were obtained in cyclic voltammetry. The sensitivity of the obtained measurements was significantly improved when a surfactant, sodium dodecyl sulfate (SDS), was present in the supporting electrolyte solution. The method of square-wave voltammetry was used to determine the linear relationship between the current and natamycin concentration. The linear relationship was obtained in the concentration range from 9.75 × 10−8 to 1.16 × 10−6 mol·L−1. In optimum conditions, i.e., 0.05 mol·L−1 H2SO4 containing 5.07 × 10−4 mol·L−1 SDS at the potential of 0.81 V (vs. SCE), the limit of detection was 3.1 × 10−8 mol·L−1. The method has good precision, which is proved by low relative standard deviation (approx. 1%). The obtained values of recovery prove the accuracy of the proposed procedure. The developed procedure was successfully tested for the assay of natamycin in single-ingredient and multi-ingredient pharmaceutical preparations and in wine samples.

Electrochemical and analytical performance of cathodically pretreated boron-doped diamond electrode for the determination of oxazolidinone antibiotic linezolid in cationic surfactant media

The electrochemical oxidation of an oxazolidinone class of antibiotic, Linezolid (LNZ) was studied in aqueous as well as aqueous/surfactant media on a commercially available boron-doped diamond (BDD) electrode pretreated cathodically. By using cyclic voltammetry, LNZ showed two couples of oxidation/reduction peak in aqueous solutions. The electrode process is pH-dependent and controlled by diffusion. The compound yielded two well-separated oxidation steps in acidic, neutral and alkaline media by employing square-wave voltammetry. The sensitivity of the voltammetric measurements was improved when the cationic surfactant, cetyltrimethylammonium bromide (CTAB) was present in the electrolyte solution at pH 4.0. In Britton-Robinson buffer containing 0.9 mM CTAB, the calibration curves were linear for both oxidation peaks (Ia and IIa) over concentration ranges of 0.25–6.41 μg mL−1 (0.74–19.27 μM), with detection limits of 0.05 μg mL−1 (0.15 μM) for Ia, and 0.12 μg mL−1 (0.34 μM) for IIa. The practical applicability of developed methodology was tested in pharmaceutical formulations.