Green synthesis of CaO nanoparticles conjugated with l-Methionine polymer film to modify carbon paste electrode for the sensitive detection of levofloxacin antibiotic

This work is aimed to use eggshells waste as a cheap precursor for the green synthesis of CaO nanoparticles. The prepared nanoparticles were characterized using XRD, FTIR, and SEM then conjugated with l- Methionine polymer film to modify carbon paste electrode. The modified electrode was used for the first time for sensitive and selective detection of levofloxacin (LEV) electrochemically. The electrochemical investigations of LEV showed that the utilized modifiers enhanced the electrocatalytic efficiency of the fabricated sensor resulting in a noticeable increase in the oxidation peak current when compared to unmodified CPE. The newly electrochemical sensor displays a good performance for detecting LEV and values of 0.64 × 10−9 M and 2.13 × 10−9 M for LOD and LOQ were obtained respectively. From other hand the collected results indicated two linear ranges, from 7.00 × 10−9 –1.00 × 10−7 M and from 1.00 × 10−7 – 3.00 × 10−6 M. Additionally, the manufactured sensor offered satisfactory selectivity toward LEV in the presence of various interferences, good stability, and reproducible response. Additionally, the suggested method was applied to determine LVS in biological samples and pharmaceutical formulation with recoveries between 96.50 to 100.55%.