Novel Drug Carriers Based On One-Dimensional Nanomaterials

One-dimensional nanomaterials, with unique structure, composition, and properties, show their high specific area and excellent hemical properties. In recent years, synthesis, functionalization and application of the one-dimensional nanomaterials have been greatly attracted great attention, but its practical use in the biological and medical applications is greatly hampered due to its low hydrophilicity, potential cytotoxicity. So its surface functionalization of one-dimensional nanomaterials become the key issues. Functionalized methods usually include noncovalent and covalent modification. Functionalization of one-dimensional nanomaterials with chemical groups (carboxyl groups, carbonyl groups, amino groups, etc), could greatly improve their solubility and biocompatibility. Thus, functionalized novel one-dimensional nanomaterials could be used as delivery systems for the proteins, nucleic acids and anti-cancer drugs.Carbon nanotubes and halloysite nanotubes have shown great promise in biology, and medicine due to their high surface area, unique structure and components. The surface functionalization of these one-dimensional nanomaterials are firstly carried out. In our study, novel anti-cancer drugs, gene drugs carriers were developed, in order to improve antitumour activity of drugs.This paper is focused on the functionalization of multi-walled carbon nanotubes and halloysite nanotubes, their applications in the biomedical field, which are demonstrated as follows:1. Supramolecular Assembly and Antitumor Activity of Multiwalled Carbon Nanotube–Camptothecin Complexes.The multiwalled carbon nanotubes were attached with the tri-block copolymer (Pluronic P123) to render high aqueous solubility. The novel supramolecular complexes were prepared with a water-insoluble anticancer drug camptothecin (CPT) loading onto functionalized multiwalled carbon nanotubes viaπ-stacking, in order to improve their solubility and antitumor activity. Furthermore, in vitro cytotoxicity studies of f-MWNTs-CPT supramolecular complexes using the MTT assay exhibit enhanced antitumor activity compared with free CPT, suggesting that the functionalized multiwalled carbon nanotubes can facilitate intracellular delivery of anticancer drug and improve drug activity. 2. Targeted and fluorescence labeling functionalized of multi-walled carbon nanotubes-anticancer drugs PTX carriers.The multiwalled carbon nanotubes were firstly modified with PEI molecules . Folic acid and quantum dots as targeting and fluorescence agent, more than conjugated to PEI modified carbon nanotubes by aqueous 1-(3-(dimethylamino)propyl) -3-ethylcarbodiimide hydrochloride (EDC). These functionalized of multi-walled carbon nanotubes exhibited good aqueous solubility, biocompatibility, and high targeting efficiency. Further, PTX were successfully binded to these drug delivery transporters mainly through noncovalentπ-interaction and hydrophobic interactions. The MTT assay results show that MWNTs-PEI-FA complexes are ideal vehicle for in vivo anticancer drug transporters and hereby enhance the cellular uptake of the drug.3. Construction and cellular effects of functionalization halloysite nanotubes-ASODNs complexes.The halloysite nanotubes were firstly coated with the organic silane to render high aqueous solubility and surface charge. Then fluorescent molecules FAM labeling antisense nucleic acid oligosaccharides loaded onto surface of functionalized halloysite nanotubes by electrostatic interaction. Thus, functionalization halloysite nanotubes-ASODNs complexes were obtained. The experimental data show that with the functionalized halloysite nanotubes, efficient intracellular delivering, cell nucleus localization and transporting efficiency of ASODNs were achieved. Furthermore, the Halloysite-ASODNs-FAM complexe have high antitumor activity. Therefore, these functionalization halloysite nanotubes could hold great promising in biomedical field.