Dual-modal MRI phantom with tunable iron deposition via coaxial electrospinning for neuroimaging validation

Reliable phantoms for validating diffusion tensor imaging (DTI) and T 2 /T 2 ∗ mapping are crucial for standardizing neuroimaging, especially in the context of iron-related neurodegeneration. Here, a novel dual-functional MRI phantom is developed using coaxial electrospinning to embed Fe 3 O 4 nanoparticles within polycaprolactone (PCL) microfibres. The resulting hollow, axon-mimicking fibres exhibit tunable magnetic and mechanical properties that simulate iron deposition in neural tissue. The phantom's architecture and Fe 3 O 4 concentration modulate fractional anisotropy, mean diffusivity, and relaxation times, effectively recapitulating MRI signatures observed in diseases like Alzheimer's and Parkinson's. Comprehensive physicochemical characterization confirms structural fidelity, thermal behaviour, and anisotropic mechanical response. Crucially, the phantom enables simultaneous DTI and T 2 /T 2 ∗ imaging under clinical MRI protocols, offering a standardized, reproducible platform for imaging validation and harmonization. This multifunctional approach bridges a critical gap in quantitative neuroimaging and presents a new class of intelligent biomaterials for MRI system calibration and pathology modelling. A multifunctional MRI phantom is developed using co-electrospun hollow fibres embedded with Fe 3 O 4 nanoparticles to simulate iron accumulation in brain tissue. The phantom supports dual-modal T 2 and T 2 ∗ MRI contrast, enabling precise validation of neuroimaging techniques. This platform bridges materials engineering and medical imaging, offering new tools for diagnosing and monitoring neurodegenerative diseases.