Inorganic nanoparticles for diagnostics, drug delivery and therapy for solid tumors

Solid tumors continue to be a major cause of mortality worldwide, with limitations in available therapies such as toxicity, nonspecificity, multidrug resistance and heterogeneity in the tumor microenvironment (TME). Inorganic nanoparticles (NPs) are multifunctional tools that overcome these limitations by enabling better imaging, targeted drug delivery and combined therapies on a single platform. This review carefully examines the current landscape of inorganic NPs, including gold NPs, mesoporous silica NPs, iron oxide-based NPs, superparamagnetic NPs, quantum dots, copper-based NPs, up conversion and carbon-based nanomaterials, with an emphasis on design, surface functionalization strategies and TME-responsive behavior. The solid TME, characterized by hypoxia, low pH, high free radicals, elevated glutathione levels and increased pressure, is a target for stimulus-responsive nanoplatforms enabling tumor-specific activation. This review provides an advanced, integrated framework for researchers and clinicians advancing inorganic NP-based precision oncology.