8 / 2023-04-23 16:06:31

Lignin-based controlled release systems for the targeted delivery of pesticide

Lignin,Controlled release,Biomass,Nanostructures,Pesticide delivery

The low utilization efficiency of pesticides significantly hampers the improvement of agricultural production. To address this issue, it is crucial to develop a green, efficient, and multifunctional pesticide carrier system. Such a system would meet the demand for sustainable agricultural practices. Constructing an efficient carrier system using green materials, particularly renewable biomass materials, can improve the spatial and interfacial transport behavior of pesticides, thus enhancing the targeted delivery rate. Lignin, one of the three primary components of biomass stands as a significant byproduct of the pulp and paper industry. Notably, lignin possesses characteristics such as UV resistance, antioxidant properties, and amphiphilicity. Previous research has demonstrated its remarkable potential in the development of green pesticide adjuvants and carrier systems. However, existing methods for preparing or applying lignin-based natural polymer pesticide carrier systems, including nanoparticles, capsules, emulsions, and Pickering systems, often involve substantial usage of organic solvents. This not only increases production costs but also poses substantial environmental risks, greatly limiting their practical application and wider adoption. To address these challenges, this study proposes the utilization of alkali lignin as the primary raw material for preparing pesticide carrier systems. Through purification, classification, and modification of lignin, the molecular structure can be precisely regulated to obtain lignin molecules with varying hydrophilicity, hydrophobicity, and charged properties. These modified lignins serve as precursors for constructing aqueous aggregates, facilitating pesticide encapsulation, UV protection, and sustained release, hence enhancing pesticide utilization efficiency. By investigating the aggregation behavior of lignin under different proportions, concentrations, solution ionic strengths, and pH values, the study sheds light on the phase boundaries, key influencing factors, and construction mechanisms of lignin aggregates. Additionally, the research examines the structure, physical properties, drug-loading characteristics, and application properties of these aggregates to reveal their effects, mechanisms, and regulatory methods for enhancing targeted pesticide delivery.