Lignin as a Dual-Function Stabilizer for Protecting PCL Nanoparticles from Photodegradation and Enhancing Atrazine Delivery

High Resolution Image Download MS PowerPoint Slide In this study, we developed poly(ε-caprolactone) (PCL) nanoparticles (NP) stabilized with fractionated lignin and evaluated their effectiveness in atrazine (ATZ) encapsulation, photoprotection, and herbicidal activity. The NP were synthesized using the emulsion-evaporation method and characterized by dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), and atomic force microscopy (AFM). High-performance liquid chromatography (HPLC) was used to determine encapsulation efficiency (EE%) and monitor ATZ degradation under UV exposure. The lignin-stabilized NP exhibited superior UV protection, reducing ATZ photodegradation by 32% compared to the commercial formulation. KL_30% was the most effective stabilizer, increasing EE% by 15% relative to the control formulation. Herbicidal assays demonstrated that KL_30%-stabilized NP achieved 28% higher weed inhibition in Bidens pilosa and 21% higher inhibition in Amaranthus viridis, particularly at reduced doses, compared to both the commercial formulation and PVA-stabilized NP. These results highlight the potential of lignin-stabilized NP as an eco-friendly alternative for controlled herbicide delivery, offering enhanced photoprotection and prolonged efficacy for sustainable weed management.