Preparation of Alginate/AgNP Nanocomposite Hydrogels Incorporating Olive Leaf Extracts in Natural Deep Eutectic Solvents

Imagine a hydrogel that not only heals but also fights bacteria—now imagine it made with olive leaves and a green solvent. That's exactly what scientists have achieved.

Scientists have crafted a smart hydrogel using alginate, silver nanoparticles, and olive leaf extract, all held together by a natural deep eutectic solvent (NADES). This green solvent—a mix of glucose, lactic acid, and water—does triple duty: it extracts bioactive compounds from olive leaves, crosslinks the alginate, and reduces silver ions into nanoparticles during gel formation. The result? A multifunctional material with impressive abilities.

In lab tests, the hydrogel swelled to 538% of its weight in under three hours and retained 90% water after four hours—key traits for wound dressings. The silver nanoparticles inside averaged 103.2 nm in size, with a concentration of 1.2 × 10⁸ particles per milliliter.

But the real star is its antibacterial power. Against foodborne pathogens, the hydrogel showed significant activity, especially against Staphylococcus aureus (79.1% inhibition), Escherichia coli (64.9%), Yersinia enterocolitica (60.6%), and Bacillus cereus (55.3%) at just 1 mg/mL. This eco-friendly approach could revolutionize how we fight infections—naturally.

Key Points

• NADES acts as extractant, crosslinker, and reducer in one.
• Hydrogel swells 538% and retains 90% water.
• Kills 79% of S. aureus at 1 mg/mL.