Revisiting the Green Synthesis of Nanoparticles: Uncovering Influences of Plant Extracts as Reducing Agents for Enhanced Synthesis Efficiency and Its Biomedical Applications

Abstract

Background: Conventional nanoparticle synthesis methods involve harsh conditions, high costs, and environmental pollution. In this context, researchers are actively searching for sustainable, eco-friendly alternatives to conventional chemical synthesis methods. This has led to the development of green synthesis procedures among which the exploration of the plant-mediated synthesis of nanoparticles experienced a great development. Especially, because plant extracts can work as reducing and stabilizing agents. This opens up new possibilities for cost-effective, environmentally-friendly nanoparticle synthesis with enhanced size uniformity and stability. Moreover, bio-inspired nanoparticles derived from plants exhibit intriguing pharmacological properties, making them highly promising for use in medical applications due to their biocompatibility and nano-dimension.

Objective: This study investigates the role of specific phytochemicals, such as phenolic compounds, terpenoids, and proteins, in plant-mediated nanoparticle synthesis together with their influence on particle size, stability, and properties. Additionally, we highlight the potential applications of these bio-derived nanoparticles, particularly with regard to drug delivery, disease management, agriculture, bioremediation, and application in other industries.

Methodology: Extensive research on scientific databases identified green synthesis methods, specifically plant-mediated synthesis, with a focus on understanding the contributions of phytochemicals like phenolic compounds, terpenoids, and proteins. The database search covered the field's development over the past 15 years.

Results: Insights gained from this exploration highlight plant-mediated green synthesis for cost-effective nanoparticle production with significant pharmacological properties. Utilizing renewable biological resources and controlling nanoparticle characteristics through biomolecule interactions offer promising avenues for future research and applications.

Conclusion: This review delves into the scientific intricacies of plant-mediated synthesis of nanoparticles, highlighting the advantages of this approach over the traditional chemical synthesis methods. The study showcases the immense potential of green synthesis for medical and other applications, aiming to inspire further research in this exciting area and promote a more sustainable future.

Keywords: biocompatibility; biomedical application; green synthesis; medicinal plants; nanomaterials; surface functionalization.

Figure 1

Schematic illustration of the method and mechanism involved in green synthesis of nanoparticles using plants as reducing agents.

Scheme 1

A plausible mechanism for AgNP synthesis using plant extract containing gallic acid.

Scheme 2

Mechanism underlying the formation and stabilization of gold nanoparticles (AuNPs) using flavonoids present in plant extracts.

Scheme 3

Photo-induced bio reduction of Ag⁺ to Ag⁰ nanoparticles using biological agents.

Scheme 4

The green synthesis of AgNPs utilizing plant extract-derived proteins as efficient reducing agents.

Figure 2

The impact of diverse factors on the morphology and yield of nanoparticles.

Figure 3

Illustrative representation of different sized and shaped nanoparticles with their potential application.

Figure 4

Diverse mechanisms involved in the antimicrobial activities exhibited by metal and metal-oxide nanoparticles.