Electrochemical determination of levofloxacin drug at poly(clayton yellow)/carbon paste electrode

A cost-effective method for the sensitive detection of levofloxacin using a 3D composite electrode composed of nail polish, graphite and aluminium oxide

The potential impact on human health and the environment has spurred significant interest in detecting and quantifying pharmaceutical compounds across various matrices, from environmental to biological samples. Here, we present an electrochemical approach for determining levofloxacin in drug, synthetic urine, water, and breast milk samples. An affordable sensor was constructed using 3D printing and composite material based on nail polish, graphite, and aluminum oxide. The conductive composite material was characterized spectroscopically, electrochemically, and by imaging techniques. Subsequently, an electrochemical method based on square wave voltammetry was optimized and applied. The method exhibited good sensitivity (5.11 ± 0.0912 μA L μmol-1 cm-2) and enhanced stability (RSD = 7.2%), with electrochemical responses correlating with the concentration of levofloxacin in the samples tested, yielding recovery values in the range of 98 to 111%. The developed method demonstrated a robust linear working range from 2 to 100 μmol L-1 and a nanomolar detection limit of 128 nmol L-1, rendering it suitable for quantitative analysis. The sensor also shows promise as a platform for the sensitive detection of pharmaceutical compounds, contributing to greater safety and sustainability in these domains.

Effectively Reinforced α-Bi2O3 MPs/PDA-RGO Sensor for Selective Modality Sensing of a Hazardous Phenolic Compound

The phenolic compound trichlorophenol (TCP) is an ingredient in fungicides and herbicides. This compound's high stability, bioaccumulation, toxicity, and poor biodegradability result in severe environmental and biological health issues. Consequently, it is crucial to have an affordable and sensitive method for detecting TCP in environmental samples. In this study, α-phase bismuth oxide microplates and polydopamine-functionalized reduced graphene oxide (α-Bi2O3 MPs/PDA-RGO) were synthesized using a simple ultrasonic method and characterized with various analytical and physical characterizations. The conversion of the catechol moieties present in the resulting PDA-RGO material into quinones facilitates productive interactions with diverse functional groups, such as hydroxyl, amine, and imine. Consequently, the compounds 2,4,6-trichlorophenol (TCP) engages in electrochemical interactions with the aforementioned functional groups. As a result, TCP shows more excellent selectivity on the designed α-Bi2O3 MPs/PDA-RGO/SPCE sensor. Under the optimized conditions, the sensor demonstrated a lower detection limit (0.0042 μM), a limit of quantification (0.0078 μM), good sensitivity (2.24 μA μM-1 cm2), a wide linear range (0.019-190.7 and 212.7-1649 μM), and pinpoint specificity. The efficacy of the sensor is additionally validated through the accurate identification of TCP residues in water, soil, and food samples.

Electrocatalytic Determination of the antibiotic Levofloxacin using modified carbon paste electrode with a poly‐murexide thin film voltammetrically

In this work, a simple, cheap, sensitive, and selective modified carbon paste electrode is proposed for the electroanalytical determination of Levofloxacin (LEVO), the drug used to treat pneumonia caused by coronavirus. The electrochemical polymerization method was applied to create a thin poly‐murexide film (POMUR) on the bare carbon paste electrode (BCPE) surface to enhance its electrocatalytic activity. The peak current response of LEVO obtained by POMUR/CPE was increased by 14.2 μA compared to BCPE. Scanning electron microscopy (SEM) and cyclic voltammetry (CV) techniques were employed to characterize BCPE and POMUR/CPE. Under the optimal experimental circumstances, the prepared sensor was capable of determining LEVO with a low limit of detection (LOD) of 7.18 nM (S/N = 3) for a linear dynamic range of 25 – 1 × 103 nM utilizing differential pulse voltammetry (DPV). Moreover, the practical applicability of POMUR/CPE for determining LEVO in pharmaceutical formulations and biological samples (human serum) demonstrated high sensitivity and selectivity with a recovery of 95.08 – 100.5 %.

Electrochemical monitoring of levofloxacin using a silver nanoparticle-modified disposable device based on a lab-made conductive ink

The emergence of bacteria genetically resistant to first- and second-generation fluoroquinolones has resulted in increased consumption of levofloxacin (LEV) in human and veterinary medicine. In this regard, the development of low cost and good sensitivity electrochemical devices has been highly required. Thus, in this work, we propose the development of a disposable electrochemical device (DED) using a lab-made conductive ink based on graphite powder and nail polish immobilized on a rigid polyvinyl chloride support (transparent sheet). Additionally, a simple and quick protocol for the electrodeposition of silver nanoparticles was used in order to improve the electroanalytical performance of the sensor (2.75-fold). A differential pulse voltammetry (DPV) method was optimized and the sensor was applied for LEV monitoring in pharmaceutical formulation samples, synthetic urine and simulated body fluid. The method showed a wide linear working range ranging from 0.5 to 50 μmol L^-1 and a detection limit of 68.3 nmol L^-1. Furthermore, the precision was adequate (RSD < 4.7%), while the accuracy was evaluated through spiked samples with percent recovery ranging from 93 to 103%. The sensor was also shown to be selective for LEV against other electroactive antibiotic species, thus demonstrating suitable characteristics for electroanalytical applications.