Antibiotics are a novel class of contaminants that represent a substantial risk to human health, making their detection an important task. In this study, ZnO nanostructures were prepared starting from Bombyx mori silk fibroin and Zn(NO₃)₂, using thermal treatment. The resulting ZnO structures were characterized using SEM, FT-IR, and XRD. They had a fibrous morphology with a wurtzite crystalline structure, with nanometric dimensions. FT-IR and XRD confirmed silk fibroin’s disappearance after thermal treatment. To prepare modified electrodes for amoxicillin (AMX) antibiotic detection, ZnO nanostructures were mixed with Nafion polymer and drop-casted on an electrode’s surface. Parameters such as drying time and concentration appeared to be important for electrochemical detection. Differential pulse voltammetry (DPV) was sensitive for AMX detection. The measurements revealed that the novel electrode based on ZnO nanostructures embedded in Nafion polymer has potential to be used for AMX electrochemical detection.

Estrogens, widely used for therapeutic or contraceptive purposes, act as endocrine disruptors in aquatic systems and have adverse effects on a wide range of living organisms. Wastewater insufficiently treated by conventional methods is the main way for estrogens to enter aquatic systems. Therefore, the purpose of this paper is to develop a novel photocatalytic system for the removal of the estrogenic mixture estradiol valerate/norgestrel from wastewater. The photocatalytic modules are operated in a plug flow reactor system under a UV-A radiation field, and the photocatalyst (TiO₂, ZnO or TiO₂/ZnO) is immobilized on an inert support of glass balls that are strung on stainless-steel wire and arranged in rows along the photocatalytic modules. The photocatalysts were synthesized by the sol–gel method and then deposited on the inert glass support by the hot method, after which it was calcined for two hours at a temperature of 500 °C. The experimental results showed that the efficiency of photocatalytic degradation largely depends on the dose of photocatalyst. The dose of photocatalyst can be adjusted by adding or removing photocatalytic modules, each of which have an approximately equal amount of photocatalyst. The best result was obtained for the TiO₂/ZnO photocatalyst, the organic substrate being practically mineralized in 120 min, for which only two photocatalytic modules are needed.