Affinity-driven functionalization of magnetic nanoparticles using tryptophan-isatin for potential bio-applications.

Aims: This study aims to develop biocompatible magnetic nanoparticles (MNPs) functionalized with tryptophan (Trp) and isatin (Isa), two biologically active molecules with known blood-brain barrier permeability and anticancer activity. The primary objective was to evaluate the potential of these functionalized MNPs for glioblastoma therapy.

Methods: Trp and Isa were conjugated onto MNPs, and the resulting nanomaterials were characterized using SEM-EDS, FTIR, XPS, and DLS. The U-87 human glioblastoma cell line was used to investigate cellular uptake, cytotoxicity (MTT assay), and radiosensitizing effects. Additional molecular insights were obtained through STRING-based network analysis.

Results: The synthesized MNPs exhibited spherical morphology with a uniform size of approximately 100-110 nm. No significant cytotoxicity was observed at concentrations up to 10 µg/mL under standard culture conditions. However, a 70% reduction in cell viability was achieved following radiotherapy when cells were pretreated with Trp-Isa functionalized MNPs. STRING analysis revealed that Trp and Isa are involved in molecular pathways associated with glioblastoma.

Conclusion: These findings suggest that Trp and Isa functionalized MNPs hold promise as a targeted and radiosensitizing nanoplatform for glioblastoma treatment. The approach also highlights broader potential for such engineered nanoparticles in the field of nanomedicine.