Superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized via co-precipitation using FeCl₃·6H₂O, FeSO₄·7H₂O, and a 25% aqueous NH₄OH solution under ultrasonic and inert conditions. SPIONs were surface-functionalized with citric acid (CA) to enhance colloidal stability and dispersion. The modified SPIONs were incorporated into a 10wt.% poly(vinyl alcohol) (PVA) matrix to prepare a homogeneous solution. PVA/SPION fibers were then fabricated via electrospinning under the following conditions: voltage, 15kV, tip-to-collector distance, 12.5cm, and a feed rate, 0.5mL/h. The resulting nanofibers exhibited uniform morphology and distribution, suitable for biomedical and environmental applications.

Powder X-ray Diffraction confirmed average crystallite sizes of 25nm for all samples. Patterns of the samples show magnetite (Fe₃O₄) spinel structure at (111), (220), (311), (400), (422), (511), (440), and (533) planes, confirming preservation of crystallinity after CA functionalization and electrohydraulic treatment. FTIR Spectroscopy showed the disappearance of the free C=O band (1720cm⁻¹) and the emergence of COO⁻ stretching bands at 1558 and 1362cm⁻¹, proving the successful surface coordination of CA to the nanoparticle surface. Mössbauer indicated dominant magnetite with hyperfine fields, with - 47T, 42–44T, and a high-IS Fe(III) component confirming CA binding. DLS and zeta potential analysis revealed size reduction from ~186nm (Bare) to 70–106nm (CA-SPIONs) and charge reversal from +25mV to –52mV, ensuring colloidal stability. VSM confirmed superparamagnetic behavior with saturation magnetization values of 60.2emu/g for bare SPIONs, 51emu/g -CA-SPIONs, and 59emu/g -CA-SPIONs after electrohydraulic treatment. Raman spectroscopy revealed a mixed magnetite–maghemite phase in CA-SPIONs, enhancing the A₁g Fe–O band and preventing oxidation. The Fe-O signal persisted after embedding in PVA nanofibers, confirming stable incorporation and preservation of magnetic structure. SEM analysis revealed that the nanofibers ranged between 200 and 400nm in diameter, with a 310nm mean and 270nm median value.

These superparamagnetic nanofiber composites, characterized by nanoscale dimensions, superparamagnetic behavior, and surface stability, are suitable for biomedical applications, targeted drug delivery, hyperthermia treatments, and tissue engineering scaffolds.