Dual-component stimulated Raman scattering imaging reveals enhanced persistence of silicon-based nanocarrier-delivered pesticides in tea.

Nanopesticides with improved utilization efficiency and reduced application rates have attracted increasing attention as promising pesticide delivery systems. However, the lack of in vivo visualization techniques in crops limits understanding of their transport behavior, controlled-release mechanisms, and efficacy. Here, we developed a dual-component imaging strategy for simultaneously tracking silicon nanocarriers and acetamiprid in tea leaves. By introducing cyano groups with distinct bioorthogonal Raman signals onto silicon nanocarriers and loading acetamiprid, a nanopesticide probe with distinguishable Raman fingerprints for both carrier and pesticide was constructed. Using stimulated Raman scattering (SRS) imaging combined with multilayer depth scanning, the penetration, migration, and spatial distribution of both components were dynamically monitored in situ. The silicon nanocarriers delivered acetamiprid into leaf tissues, reaching a depth of approximately 20 μm within 2 h. Although the nanopesticide exhibited slightly lower initial penetration than free acetamiprid, it significantly enhanced pesticide retention, resulting in greater accumulation in tea leaves after 24 h. This dual-component visualization approach provides direct evidence of nanocarrier-mediated pesticide transport and persistence in plant tissues. The findings advance the understanding of nanopesticide fate in crops and provide a valuable tool for optimizing pesticide delivery systems, improving pesticide utilization efficiency, and supporting more rational pesticide application strategies.