Analytical & Bioanalytical Electrochemistry
Volume:16 Issue: 1, Jan 2024

The corrosion of aluminum beverage cans poses a significant industrial challenge that causes economic and health problems. However, there exists a requirement to gather scientific data that can offer knowledge to the food and packaging sectors, aiding in enhancing materials and reducing losses linked to this issue. This research examined how aluminum cans interacted with beverages using model solutions containing copper and chloride concentrations close to those typically found in beverages. This research highlights the influence of the temperature (20-50 °C), chloride concentration (25-1000 mg/L), and copper concentration (25-1000 µg/L) as independent variables on the corrosion of Al can in citric acid solution using Response surface methodology (RSM) with the Box–Behnken design (BBD). The input corrosion current density was assessed through potentiodynamic polarization tests conducted under variable conditions outlined in the design matrix. With p-values under 0.05 and good regression coefficients (R2), the (ANOVA) approach confirmed that the quadratic model developed was significant.  The RSM demonstrated a strong alignment between the predicted outcomes and the observed responses. The [Cl-] exhibited the most prominent and adverse impact on the dissolution of aluminum. The EIS graphs indicated that the corrosion reaction is primarily governed by the diffusion process.

Voltammetric detection of active substances has occupied an important place in the last decades. In this study, a novel highly efficient electrochemical sensor was fabricated using a combination of titanium dioxide nanoparticles and multi-walled carbon nanotubes mixed with graphene oxide sheets for the sensitive detection of the antibiotic Azithromycin.  The results show that the constructed electrode has excellent electrocatalytic activity for Azithromycin detection (pH 7) compared to the unmodified electrode due to the mobilized TiO2 nano-conductors on the MWCNTs@GO.  The electrochemical behavior of Azithromycin was perfectly reversible. Transmission electron microscopy, X-ray diffraction, infrared spectroscopy, and Raman spectroscopy analyses were performed to examine the particularities of the IL-TiO2 NPs@MWCNTs/GO/GCE interface. The effects of pH, accumulation time, scan rate, and the amount of multi-walled carbon nanotubes required for creation were investigated and optimized by applying Cyclic Voltammetry and DPV at pH 7.0. Phosphate buffer medium. The results showed that the number of protons and electrons involved in the electrooxidation reaction of Azithromycin is equal. The calibration curve was plotted in the concentration range of 10-3 to 0.5×10-6 M using the DPV method. The limit of detection and limit of quantification were calculated as 1.772×10-8 M and 5.83×10-8 M, respectively. The described method was applied to determine Azithromycin in pharmaceutical formulations and human blood and urine samples. The good recovery values between 96.6% and 99.1% suggest the applicability, efficiency, and reliability of the sensor for the determination of Azithromycin.

Buried pipeline steels are exposed to external corrosion due to the aggressive effect of the soil environment. Despite the double protection system consisting of a coating and cathodic protection, the risk of failure is present and can lead to a reduction in the structural integrity of the pipes. Considering the complexity and variability of different soils, a poor estimate of protection conditions can result in either overprotection or underprotection. The current investigation was conducted using a variety of cathodic potentials on X52 carbon steel. The samples were covered by a layer of natural clay and soaked with a simulated soil solution. Chronoamperometry measurements and electrochemical impedance spectroscopy (EIS) technique were used. The analysis of the impedance diagrams revealed significant variations in form and characteristics when the steel was exposed to different cathodic potential degrees. It was also noticed that the charge transfer resistance decreased gradually at lower applied cathodic potentials. On the other hand, it was observed that the passive layer protectiveness could be evaluated by the EIS method. In this study, it was clearly shown that the EIS technique can be used as a method to monitor and control the performance of cathodic protection.

In developing countries, most women are suffering from endometriosis disease and unfortunately, there is not yet an efficient and adaptable biomarker that could be explored further for the diagnostics of endometriosis. In this direction, we are proposing interleukin-10 (IL-10) as a better biomarker and its efficient electrochemical immunosensing at an ultra-low level for the diagnosis of endometriosis based on demonstrated high sensitivity and specificity. To develop the proposed sensing platform, a glassy carbon electrode (GCE) was electrochemically modified with gold nanoparticles (AuNPs) utilizing the chronoamperometric method. Further, the Au/GCE platform was functionalized using a cysteamine-self-assemble monolayer through glutaraldehyde to achieve successful immobilization of the monoclonal IL-10 antibody and selective detection of IL-10 in real samples as well. The interaction between monoclonal IL-10 antibody and IL-10 antigen was studied using square wave voltammetry (SWV) technique. The cysteamine-based immunosensor displayed a dynamic range from 1 atto gram (ag i.e., 10-18 g) to 5 pico gram (pg i.e., 10-6 g) per mL, and the lower detection limit of 0.33 ag per mL of IL-10 was obtained. The validation of achieved sensing performance was evaluated by comparing all the parameters regarding the Enzyme-linked immunosorbent assays (ELISA). Additionally, the developed sensing platform exhibits high sensitivity, specificity, and reproducibility together with high stability and provides an effective appose to detect IL-10 cost and time-effective compared to ELISA. Thus, such AuNPs-based IL-10 sensing platforms of high-performance features can be promoted as an efficient analytical tool for clinical application to support women's healthcare globally.

This work focuses on applying a combined process combining electro-Fenton (EF) pretreatment with biological degradation to mineralize the antiviral Ribavirin in an efficient, economical and ecological manner. First, the main experimental parameters affecting the efficiency of the electro-Fenton process, namely applied current intensity, Fe(II) catalyst concentration and initial Ribavirin concentration were evaluated and optimized. Indeed, the mineralization rate reaches maximum residual values of 99% after 4 hours of electrolysis applying a current of 200 mA. This mineralization is accompanied by an increase in biodegradability, evaluated from the BOD5/COD ratio, which goes from 0.04 at the beginning of treatment (1 h) to 0.45 after 2 hours of electrolysis, demonstrating the feasibility of a biological treatment. In addition, the energy efficiency decreased when the treatment time was extended due to the limitation of mass transport. Thus, the feasibility of coupling electro-Fenton and biological treatment has been successfully demonstrated on a laboratory-scale was, achieving a 96.66% removal rate by the Bio-EF process. A Box-Behnken design based on response surface methodology was applied to develop a model for predicting Rib removal rate. The interaction of factors such as Rib concentration (X1), catalyst concentration (X2) and electrolysis time (X3) was analyzed to identify optimal operating conditions. The model results obtained are statistically significant with an R2 of 0.99, indicating that the proposed model is significant and relevant. In addition, the iso-response curves obtained enabled us to determine the optimal experimental conditions required for effective mineralization of the targeted antiviral.

Metal-organic frameworks (MOFs) have become a highly promising porous material for the detection of cancer biomarkers due to their special characteristics, such as permanent porosity and tuneable pore size. Such advantages make MOFs well-suited for use in biosensing applications. In this review, a comprehensive overview of the use of MOFs in the electrochemical detection of bioorganic materials has been provided. We begin by discussing the adjustable surface areas and porosity of MOFs, which are crucial for their applicability in biosensing. The ability to control the porosity of MOFs allows for the efficient capture and detection of specific biomarkers. Furthermore, the presence of functional sites on MOF surfaces enhances their sensitivity and selectivity towards target molecules. In the next step, we investigated different biosensors for the detection of cancer biomarkers that have used MOF to improve their performance. These biosensors utilize the unique properties of MOFs to selectively bind and detect specific biomarkers associated with different types of cancer. The high sensitivity and selectivity of these biosensors make them promising tools for early cancer diagnosis and monitoring.