Fabrication of hybrid nanocomposites for electrochemical evaluation of food-based preservative and bioactive targets of hydrogen peroxide and rutin in real fruit and drug samples

Development of a reliable tool to detect hydrogen peroxide (H2O2) and rutin in food-derived products and bioactive flavonoids is essential for food safety. Nevertheless, food/drug-based real samples are complex matrices that affect the sensor's specificity and sensitivity. For this purpose, we developed a simple electrochemical detection platform using covalent organic framework‑silver nanoparticles (COF-AgNPs). Based on spectral and electrochemical tests, COF-AgNPs displayed enhanced electroactive sites and facile electron transfer. For H2O2 and rutin, the designed sensor surface exhibited outstanding concentration linearity of 0.5 nM–1000 μM and 1 nM–900 μM, respectively, along with superior detection limits of 0.126 nM and 0.133 nM. Additionally, it demonstrated acceptable reproducibility and interference capability. In practical analysis, H2O2 and rutin were detected in milk, fruits, and drug samples with high recovery rates of 94.60–99.31 % (n = 3). Consequently, the designed sensor is ideal for screening targets for H2O2 and rutin in food sources and for food research. Development of a covalent organic framework and its hybrid nanocomposites for electrochemical detection of hydrogen peroxide and rutin in real milk, fruit, and drug samples. [Display omitted] •An electrochemical sensor based on COF-AgNPs was designed for hydrogen peroxide and rutin detection.•The electrocatalyst exhibited superior electrocatalytic activity to targets due to a combination effect.•The electrochemical sensor showed notable concert within a wide linear range and nanomolar LOD.•The electrochemical sensor shows excellent sensitivity and selectivity and is a highly reproducible signal.•Practical application was demonstrated in sampling milk, apples, grapes, oranges, and drug samples.