Iron, owing to its active redox switching plays a pivotal role in the growth and metabolic systems as an essential part of metalloproteins. Despite being the 4th abundant element in the soil, its deficiency is fairly common in the crops due to iron being present in its unavailable state. This affects plants adversely by causing chlorosis, delay in ripening and seed setting processes, and demand advanced methods of iron delivery to prevent the physiological burden of plants while maintaining or improving their nutritional values.
Mesoporous silica nanoparticles (MS) are reported to have high surface area for drug loading, and non-toxic nature even if kept in soil for longer durations. Considering this, we have developed a MS based delivery system for the sustained delivery of iron to the plants. Further, we demonstrated that coating of chitosan over the loaded particles created a protective bio-layer, which prevented the conversion of iron to their unavailable forms. The chitosan coating used not only acted as a latent gate to control carbonate ion but also helped in targeting the roots specifically1. This system was tested in tomato.