Aims
Glioblastoma (GBM) is the most common and aggressive primary brain tumour in adults, with poor survival despite surgery, radiotherapy and chemotherapy. Treatment resistance, tumour heterogeneity and limited drug delivery across the blood–brain barrier (BBB) remain major challenges contributing to tumour recurrence and poor clinical outcomes. Iron oxide nanoparticles (IONPs) are potential radiosensitisers because of their biocompatibility and ability to enhance radiation-induced oxidative stress and DNA damage. Radiosensitisation aims to enhance specific cancer cell killing and improve patient outcomes while limiting side effects from radiotherapy. Three-dimensional (3D) tumour spheroids provide a clinically relevant preclinical model to investigate IONPs by better mimicking the tumour microenvironment and nanoparticle behaviour in tumours than conventional monolayer cell culture models. This study aimed to synthesise and characterise IONPs, and establish a reproducible 3D human GBM spheroid model for IONP evaluation for nanoparticle-enhanced chemoradiotherapy.
Methods
IONPs were synthesised using a co-precipitation method. Nanoparticles were characterised by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). SF188 cells were cultured in ultra-low attachment plates to generate 3D spheroids. Pre-formed spheroids were treated with IONPs to mimic in vivo delivery and enable evaluation of nanoparticle penetration and biological responses. Seeding density was optimised. Spheroid morphology was assessed by brightfield microscopy and viability by Live/Dead cell staining.
Results
SEM demonstrated uniform nanoscale Fe₃O₄ particles, while EDS confirmed iron and oxygen composition. XRD verified the crystalline magnetite phase, and FTIR confirmed successful surface functionalisation. Optimisation of GBM spheroid formation identified a seeding density that generated reproducible aggregates of cells with consistent morphology and high viability. Live/Dead cell staining confirmed viability throughout spheroid development.
Conclusion
A platform integrating IONPs with a 3D GBM spheroid model was established for evaluating nanoparticle penetration and nanoparticle-enhanced chemoradiotherapy in GBM.