Toward Safer Nanotechnology: Eco-friendly Strategies for Nanoparticle Fabrication

Abstract

Nanomaterials play a central role in various technological and biomedical applications due to their unique chemical and physical properties. Among the various fabrication methods, chemical reduction is the most widely used approach, offering high efficiency and precise control over particle size and concentration. However, the use of toxic reducing agents (e.g., NaBH₄, N₂H₄·H₂O) and stabilizers (e.g., PVP) in conventional synthesis has serious environmental, health, and safety risks. In response to these issues, eco-friendly strategies such as green synthesis using plant extracts have gained increasing attention as sustainable alternatives. Plant-based extracts, including polyphenols and flavonoids, can work as reducing agents and stabilisers. These reagents enable nanoparticle formation under environmentally benign and less hazardous conditions. The eco-friendly approach offers advantages in biocompatibility, environmental safety, and additional bio-functionalities (e.g., antioxidant and antimicrobial effects). However, it also faces challenges, including a lower reaction rate, higher costs, and difficulty in storing reagents. This review discusses recent advances in nanoparticle fabrication, compares conventional and green synthesis methods, and evaluates their respective benefits and limitations.