Formulation and characterization of agar-chia gum coated niosomes for controlled ferrous fumarate release

Iron deficiency remains a global nutritional challenge, requiring stable and efficient delivery systems for fortification. This study aimed to develop a novel carrier by encapsulating ferrous fumarate-loaded niosomes within a hydrogel matrix composed of agar and chia seed gum (CSG). The niosomes exhibited a uniformity (PDI < 0.22) and negative surface charge (<-23 mV), ensuring electrostatic stability. FTIR indicated that the characteristic peak of ferrous was not present in the spectrum of hybrid systems. XRD showed that successful transition of crystalline iron into an amorphous state within the carriers. Rheological assessment revealed that the agar enhanced the viscoelastic moduli (G' > G'') and mechanical strength. FESEM demonstrated non-porous surface morphology in the dual-hydrogel system, which improved thermal stability (T_m > 300 °C). Release studies highlighted that while CSG were susceptible to rapid destabilization, the dual-hydrogel (≅42.6%) matrix provided superior protection. Overall, the agar-CSG-niosome composite represents a robust platform for the fortification of functional foods.