Fabrication of ZnWO4/Carbon Black Nanocomposites Modified Glassy Carbon Electrode for Enhanced Electrochemical Determination of Ciprofloxacin in Environmental Water Samples

Fabrication of a novel HKUST-1/CoFe2O4/g-C3N4 electrode for the electrochemical detection of ciprofloxacin in physiological samples

In this work, a novel HKUST-1/CoFe2O4/g-C3N4 electrode was successfully prepared via the hydrothermal method and the high-temperature calcination method, which can be applied as an electrochemical sensor for the precise detection of ciprofloxacin (CIP) in physiological samples. The novel electrode was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR), and its electrochemical performance was further evaluated via the cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The results demonstrated that the HKUST-1/CoFe2O4/g-C3N4 electrode exhibited an optimal linear range of 0.05-180 μmol L-1 for the CIP detection, which demonstrated a low limit of detection (LOD) of 0.0026 μmol L-1 and a low limit of quantitation (LOQ) of 0.0087 μmol L-1, respectively. Additionally, the novel semiconductor sensors exhibited exceptional selectivity, stability and repeatability in the determination of CIP. The recovery rate of CIP was found to range from 98.00% to 104.00% in serum, with the relative standard deviations (RSD) below 2.62% (n = 5), while the recovery rate of CIP was found to range from 96.00% to 105.00%, with the RSD less than 3.23% (n = 5) in urine. The current study extends to the application of the semiconductor-based electrochemical sensors and offers a new approach for the clinical pharmaceutical analysis to ensure medication safety, which could provide valuable insights into the potential of semiconductor sensors for future clinical applications.

Eco-friendly, sensitive and inventive first derivative synchronous spectrofluorimetric determination of ciprofloxacin and phenylephrine in their pure form, single and combined eye drops

A facile, sensitive, accurate and green spectrofluorimetric method was evolved for the assay of ciprofloxacin hydrochloride (CFX) and phenylephrine hydrochloride (PLN) in their co-formulated eye drops with their challengeable ratio of 30:1 for CFX and PLN, respectively. Such drops are clinically used for the treatment of eye bacterial infections. They relieve the symptoms of infection by stopping further growth of the causative microorganisms. The assay principle based on first-order synchronous spectrofluorometric scan using Δ λ = 40 nm in which PLN peak amplitudes were recorded at 283.4 nm, meanwhile CFX was measured at 326.2 nm in the same scans. The calibration curves were linear within the concentration ranges: 0.02-0.5 µg/mL and 0.5-5.0 µg/mL for PLN and CFX, respectively. The method validation was confirmed following the International Conference of Harmonization (ICH) Guidelines. This suggested method was the first one that described simultaneous analysis of PLN and CFX by a spectrofluorimetric technique. In this method, green analytical procedures were implemented to lessen occupational and environmental perils and method greenness was assessed by four assessment tools. GAPI, NEMI, AGREE and Analytical eco-scale were applied to this study and it was deduced from their results that the method had high degree of greenness as it fulfilled all requirements of GAPI, NEMI pictograms and it had high scores of analytical eco scale (97) and AGREE methods (0.82). Subsequently, it was successfully applied to assay both drugs in pure forms, pharmaceutical single and co-formulated eye drops.