This second special issue of the Journal of Biomedical Nanotechnology in a series contains another 30 state-of-the-art reviews focused on the biomedical applications of nanomaterials, biosensors, bone tissue engineering, MRI and bioimaging, single-cell detection, stem cells, endothelial progenitor cells, toxicity and biosafety of nanodrugs, nanoparticle-based new therapeutic approaches for cancer, hepatic and cardiovascular disease.