Nanofertilizers for enhancing food production: A case study on microgreens enrichment using superparamagnetic iron oxide nanoparticles (SPIONs)

The study aimed to evaluate superparamagnetic iron oxide nanoparticles (SPIONS) as nanofertilizers to enrich Allium cepa vegetable productivity. The nanofertilizer was synthesized using iron salts and a weak base. Characterization via powder X-ray diffraction (PXRD), UV–Vis spectroscopy, and magnetometry confirmed Fe3O4-based nanomaterial formation. Germination assays were conducted in Petri dishes, each containing 50 seeds, with four groups tested: deionized water (G1), Fe2+ solution (G2), Fe3+ solution (G3), and SPION suspension (G4). Germination rates were 70 % for G1, 62 % for G4, 58 % for G2, and 44 % for G3. Root growth analysis demonstrated superior development in G4, indicating stimulation. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) determined higher Fe absorption in Allium cepa enriched with nanoparticles compared to non-enriched vegetables. Thus, it is concluded that the nanoparticle exhibits promising effects as nanofertilizer. •SPIONs at 667 μg L−1 significantly enhance root growth in Allium Cepa.•SPION nanofertilizer improves germination rates over ionic iron treatments.•Validated methods accurately quantify Fe uptake in microgreens enriched with SPIONs.•SPIONs show distinct Fe absorption patterns, optimizing nutrient delivery in plants.