Researchers have used a plant enzyme to synthesize1 gold nanoparticles (GNPs) that boosts the immune response of Bombyx mori , an economically important silkworm. This offers an eco-friendly way of making GNPs that will be useful for medical and biotechnological applications.

The synthesis of nanoparticles with well-defined size, shape and composition is a big challenge in the field of nanotechnology. The plant-mediated biological synthesis of nanoparticles has gained significant attention in recent years, owing to its eco-friendly nature.

To devise a nontoxic way of synthesizing GNPs with medicinal properties, the researchers isolated β-glucosidase from the leaf extract of Solanum torvum. They then used this enzyme to reduce gold salts, yielding GNPs that were spherical, triangle and oval in shape, with diameters of 8–22 nm.

This plant-enzyme-aided technique was found to improve the defensive mechanism of Bombyx mori significantly, and reduced the GNP synthesis time from a few days to just one hour.

For molecular imaging and therapy, it is of pivotal importance to generate nanoparticles in bio-friendly media, even in the presence of chemically sensitive proteins and peptides. This technique is a single-step eco-friendly process that has been shown to be effective for the generation and stabilization of nontoxic GNPs for diagnostic and therapeutic applications, the researchers say.

The authors of this work are from: Nanoscience Division, Department of Zoology, Thiruvalluvar University, Vellore, and Department of Animal Health and Management, Alagappa University, Karaikudi, India.