Chemical Synthesis of Selenium Nanoparticles: Application Prospects

Selenium is an essential micronutrient, but its bioavailability and toxicity depend on its chemical form. Selenium nanoparticles (SeNPs) are of significant interest due to their increased bioavailability, low toxicity, and pronounced antioxidant properties compared to organic and inorganic forms of selenium. However, particle aggregation, leading to a loss of colloidal stability, remains a key challenge in their industrial application. The research investigated the method of obtaining selenium nanoparticles by chemical reduction of a selenium-containing precursor using various reducing agents. The research objective was to study the size, morphology, and stability of the resulting nanoparticles and to evaluate the prospects for their application. Stable selenium nanoparticles were synthesized by chemical reduction of selenious acid (H2SeO3) in an aqueous medium. Ascorbic acid and sodium thiosulfate were studied as reducing agents. Polysorbate 80 (Tween 80), sodium alginate, and corn starch were used to stabilize the resulting nanoparticles. The resulting solids were characterized by UV spectrophotometry to determine the selenium concentration and construct calibration curves. Particle size, morphology, elemental composition, and distribution within the samples were analyzed using scanning electron microscopy (SEM) with an energy-dispersive detector. The tests also included viscosity of the stabilized systems. Ascorbic acid proved to be a more effective reducing agent than sodium thiosulfate. The best stabilization results belonged to Polysorbate 80. The sample based on ascorbic acid and Polysorbate 80 showed a uniform distribution of selenium with the smallest particle size (0.2–0.7 microns) and the highest selenium content (3.62%). Highly viscous stabilizers provoked agglomeration. The optimal ratio of H2SeO3:reducing agent was 1:4. When ascorbic acid served as a reducing agent and Polysorbate 80 as a stabilizer, the dispersion of selenium nanoparticles was uniform, the hydrodynamic radius was tens of nanometers, and the colloidal stability was high. Such systems are promising as a source of selenium in the fortification of bakery, dairy and meat food products, as well as in innovative biofortification of crops.