Development and biological evaluation of composite fertilizers based on phosphosilicate glasses for sustainable agriculture

The development of controlled-release inorganic fertilizers is a promising strategy to improve nutrient use efficiency and reduce the environmental impacts associated with conventional fertilizers. This work investigates phosphosilicate glass fertilizers encapsulated in a biopolymer matrix as a bio-efficient delivery system for essential nutrients. The glass composition enables the incorporation of P, Si, Ca, and K into its vitreous network, while the biopolymer coating modulates nutrient release and allows nitrogen incorporation. Dissolution assays demonstrated continuous and pH-dependent ion release, with higher nutrient concentrations observed under acidic conditions and a more gradual phosphate release compared to uncoated glass. Preliminary biological evaluations indicated compatibility with the biological environment and positive effects on plant development. Ongoing ecotoxicological studies further support the environmental safety of the composite, highlighting its potential as a sustainable and low-toxicity alternative for agricultural applications.