As mentioned above, CNTs have the unique properties such as ultrahigh surface area which make them as promising potential for delivery of drugs,

peptides, and nucleic acids (Table 6). The specific drug or gene can be integrated to walls and tips of CNTs and recognize cancer-specific receptors on the cell surface, by these means CNTs can cross the mammalian cell membrane by endocytosis or other mechanisms [115] and carry therapeutic drugs or genes more safely and efficiently in the cells that are previously inaccessible [116]. BMN 673 mw More recently, researchers have developed a novel and more efficient SWNT-based tumor-targeted drug delivery system (DDS) which consists of tumor-targeting ligands, anticancer drugs, and functionalized SWNTs. If this system interacts with cancer cells, then it can induce receptor-mediated endocytosis by recognizing cancer-specific receptors on the surface of cancer cells and so efficiently and specifically release chemotherapeutic agents. Table 6 Example of drugs and nucleic acids which were delivered by carbon nanotubes Drug/nucleic acid CNT type Cell or tissue Properties Reference Taxoid SWNTs Leukemia High potency toward specific cancer cell lines [116] Doxorubicin SWNTs Colon cancer Efficiently taken up by cancer cells, then translocates to the nucleus while the nanotubes remain in the cytoplasm [113, 114] Cisplatin SWNTs Squamous carcinoma Rapid regression of tumor

growth [117] C646 ic50 Cisplatin SWNTs Nasopharyngeal epidermoid carcinoma, etc. High and specific binding to the folate receptor (FR) for the SWNT-1 conjugate [118] Doxorubicin SWNTs Breast cancer Rutecarpine Glioblastoma Show that large surface areas on

single-walled carbon nanotubes (SWNTs) [119] Doxorubicin SWNTs Cervical carcinoma Increase nuclear DNA damage and inhibit the cell proliferation [115] Radionuclide SWNTs Burkitt lymphoma The selective targeting of tumor in vitro and in vivo [120] Paclitaxel SWNTs Breast cancer High treatment efficacy, minimum side effects [121] siRNA SWNTs Tumor cells both in vitro and in vivo mouse models Increase suppression of tumor growth [122] Toxic siRNA sequence (siTOX) Functionalized MWNTs Human lung xenograft model Significant tumor growth NSC 683864 in vivo inhibition [123] siRNA SWNT Human neuroblastoma Enhance the efficiency of siRNA-mediated gastrin-releasing peptide receptor (GRP-R) gene silencing [124] SOCS1siRNA sWNT Dendritic cells (DCs) Reduced SOCS1 expression and retarded the growth of established B16 tumor in mice [125] Conclusions Nanomaterials explain probability and promise in regenerative medicine for the reason that of their attractive chemical and physical properties. Carbon nanotubes (purified/modified) have a high potential of finding unique applications in wide areas of medicine. Moreover, the encapsulation of other materials in the carbon nanotubes would open up a prospect for their bioapplications in medicine.