pH and enzyme responsive flower-like silica-based carriers for pesticide delivery

Smart environment-responsive nanopesticides hold great potential for enhancing foliar retention and utilization efficiency. We developed a pH laccase dual-responsive delivery system DFCS using flower-like silica nanocarriers FNCs modified with carboxymethyl chitosan and sodium lignosulfonate for dinotefuran delivery. The nanocarriers unique rough flower-like morphology and hydrophilic modification enabled strong foliar adhesion. DFCS achieved a high loading capacity of 39 %. The carboxymethyl chitosan sodium lignosulfonate coating served as a dual-functional barrier endowing excellent UV stability with a UV half-life of 254 min nearly four times that of commercial DNF SC and superior rainfall resistance with 45 % washout on Shanghai Green leaves versus 64 % of conventional formulations. DFCS exhibited significant insecticidal activity against Plutella xylostella with over 85 % mortality retained after 120 min of UV irradiation. This work proposes a novel nanoformulation strategy to improve pesticide efficiency and reduce environmental loss through intelligent adhesion-enhancing and dual-responsive design.