Highly Crystalline WO₃ Nanoparticles Are Nontoxic to Stem Cells and Cancer Cells

Abstract

Tungsten oxide sol, containing highly crystalline nanoparticles of orthorhombic WO 3 and having good sedimentation stability, was synthesized using a facile, ultrasonic-assisted technique. An additional steric stabilizer, dextran, was proposed to enhance the stability of WO 3 nanoparticles in biological media and to reduce their in vivo toxicity. The cytotoxicity of dextran-stabilized and nonstabilized WO 3 sols was studied in vitro using dental pulp stem (DPS) cell lines and breast cancer (MCF-7) cell lines. Both tungsten oxide sols demonstrated low cytotoxicity and low genotoxicity for both stem cells and malignant cells and only slightly reduced their metabolic activity in the concentration range studied (from 0.2 to 200 μ g/ml). The data obtained support possible theranostic applications of tungsten oxide colloidal solutions.