Ensuring global food security remains a pressing challenge due to the growing world population and accelerating climate change. Genetic modification provides a pathway to developing crops with improved traits, yet conventional approaches rely heavily on tissue culture regeneration, which is complex, time-consuming, and often impractical for many crop species. Recently, pollen magnetofection has emerged as a tissue culture-independent alternative for plant genetic transformation. In this study, we investigated polyethylenimine (PEI)-coated Fe3O4 (Fe3O4@PEI) magnetic nanoparticles (MNPs) as potential carriers for pollen-mediated gene delivery, focusing on their synthesis, characterization, and DNA-binding capacity. The Fe3O4@PEI MNPs were synthesized via a one-step in situ coating method and their properties were compared with bare Fe3O4 MNPs synthesized separately. The nanostructures were systematically characterized in terms of size, morphology, crystal structure, surface functionalization, elemental composition, and magnetic behavior, confirming successful in situ PEI coating without post-synthesis modification. Compared to bare Fe3O4 MNPs, Fe3O4@PEI MNPs displayed reduced agglomeration, a more uniform size distribution, and improved colloidal stability. The nanoparticles had an average particle size of approximately 30 nm and an enhanced DNA-binding performance: up to 6 ng of linear DNA per μg of MNPs (DNA/MNP mass ratio of 0.006:1) and complete retention of plasmid DNA across the tested range. These results support the feasibility of Fe3O4@PEI nanocarriers for pollen-directed gene delivery in plants.
Esha et al. (Thu,) studied this question.