**3. Nanomedicine in Stroke Treatment**

There are several challenges in treating ischemic stroke. Most therapeutics have short blood circulation and cannot easily cross the blood brain barrier to reach the ischemic tissues. In addition, controlling drug release and developing novel drug delivery vehicles are important factors to improve therapies of ischemic stroke. Nanotechnology is used to design nanoscale materials that can be applied in biomedical applications. Nanoparticles with the sizes of 50–200 nm are generated and can encapsulate drugs to increase drug water solubility and tissue targeting. Nanoparticles are smaller than a cell and larger than small molecules; thus, nanoparticles are excellent carriers to deliver therapeutics (drugs) and control their release for improved therapies in a wide range of diseases [42–44]. Nanoparticle-based drug delivery systems may solve the current challenges in ischemic stroke treatment. In this section, we present several nanoparticle-drug delivery systems used in treating ischemic stroke (Figure 3).

**Figure 3.** Nanoparticle-based delivery platforms for delivery of neuroprotectants, anti-inflammation reagents, and imaging probes for ischemic stroke therapy and diagnostics. Polymeric NPs include PLGA (poly(lactic-co-glycolic acid) NPs, chitosan NPs, and PAMAN dendrimer. Liposomes are made of a lipid bilayer and are loaded with therapeutics agents. Inorganic NPs include metallic NPs (such as platinum), ceria NPs, and Fe2O3 NPs. Biomimetic NPs are new drug delivery platforms generated from cell membrane vesicles. Each type of NPs has been discussed in the manuscript.
