Vitamin–Metal Synergy: Folic-Acid-Based Carbon Nanoassemblies for Optimized Plant Growth

Abstract

Developing sustainable strategies to enhance crop yields is critical to meeting global food demands under intensifying climate stress. This study investigates the synthesis and application of folic-acid-based carbon nanoassemblies (FA-CNAs) that integrate magnesium (Mg) or manganese (Mn) as precision nanobionic tools for agricultural enhancement. The produced materials were selected for photosynthetic enhancement due to their biofortification potential and their ability to expand the usable solar spectrum by harvesting underutilized UV-A wavelengths. In greenhouse trials with Raphanus sativus, FA-CNA-Mg treatment achieved significant biostimulation, resulting in a 13% increase in foliar dry mass, a 19% boost in chlorophyll concentration, and a 22% improvement in ascorbic acid content. Conversely, while FA-CNA-Mn facilitated exceptional systemic translocation (up to a 306% increase in root Mn concentration), it displayed inhibitions in the rate of the Hill reaction by 36%. Untargeted metabolomics revealed that the superior performance of FA-CNA-Mg is underpinned by systemic metabolic reprogramming, characterized by the upregulation of vitamin B5 and an accelerated flux of essential amino acids and nitrogen-rich ureides. These results highlight the potential of vitamin–metal synergy for developing high-efficiency, sustainable alternatives to conventional fertilizers that optimize both photosynthetic integrity and harvestable yield.