A brief review on optimizing biogenic selenium nanoparticle synthesis: parameters, mechanisms, and reporting standards (2020–2025)

Abstract

Biogenic selenium nanoparticles (SeNPs) are attractive for biomedical and agricultural–environmental uses, but their properties depend sensitively on process parameters. This method involves several parameters that can significantly influence the size, shape, and other properties of the biogenically synthesized SeNPs. These features directly affect the biological potential of the SeNPs. Therefore, creating efficient and suitable SeNPs with desired traits for effective biological applications requires a thorough understanding of these parameters. This mini–review critically synthesizes how pH, temperature, incubation time, precursor identity/molarity, extract: precursor ratio, and mixing influence nucleation, growth, and stability of SeNPs across plant– and microbe-mediated routes. Intracellular and extracellular synthesis mechanisms, reductase actions, and biomacromolecule encapsulation that govern nanoparticle formation and stabilization of the biogenic SeNPs are further explored. We compile typical operating windows reported from 2020 to 2025 and highlight mechanistic levers (reductant strength, caps, and mass transfer). This framework supports rational optimization and more reliable translation of SeNPs. Improved control over the SeNPs’ physicochemical properties is demonstrated via synthesis condition optimization and in-depth mechanistic insight. However, standardized reporting, reproducibility, and scalable manufacturing remain major challenges, and filling these gaps will facilitate the development of reliable, reproducible, and clinically translatable biogenic SeNPs for biomedical and industrial applications