Abstract
One of the main challenges in animal breeding systems is determining estradiol (E2) in livestock samples as simple and minimally invasive as possible, Thus, a nonenzymatic biosensor screen-printed electrode (SPE) was developed by modifying nanohybrid palladium nanoparticles (PdNPs), and carbon dots anchored on a nanosilica particle (PdNPs/C.dots/SiO(2)), denominated SPE/PdNPs/C.dots/SiO(2), and successfully tested for the direct detection of estradiol in livestock samples. PdNPs were directly obtained by a one-step synthesis through carbon dot reduction. Hybrid nanomaterials were characterized by atomic force microscopy, high-resolution transmission electron microscopy, and electrochemical impedance. The combination of PdNPs with C.dots resulted in a nonenzymatic biosensor supported on a screen-printed platform with superior electrocatalytic properties regarding the oxidation of E2 when compared to unmodified sensors. Modifications in the working electrode resulted in high sensitivity toward E2 determination within a linear range from 0.005 to 14.0 μmol L(-1) with a limit of detection of 1.0 nmol L(-1). The recovery rate of E2 in bovine serum samples and urine samples ranged from 92 to 106%. Interference studies showed that peak current variation (Δi (p)) among all interferents evaluated and E2 did not exceed ±2%. The newly developed sensor stands out not only for its high sensitivity but also for its quick and simple way of production while also being disposable after analysis, providing a simple, sensitive, and practical approach for the determination of reproductive hormones in livestock.