Study On Functionalization Of Single Walled Nanotubes And Their Preliminary Application In Medicine

Single-walled carbon nanotubes (SWCNTs) are attracting increasing attention in biomedical research because their unique physical and chemical properties offer the promise of novel diagnostic and therapeutic methods. However, due to their high aspect ratios and the strong inter-tube van der Waals interactions, SWCNTs tend to form bundles and the solubility in common solvents is very limited. Our motivation in this area is to improve the solubility and biocompatibility of SWCNTs by wrapping natural polysaccharides, then study their potentials for bio-scaffolds and medecine carriers. In addition, modified SWCNTs are also used as carriers to load Au gold nanoparticles for photo-thermal therapy. The details are as follows:(1) The widely spread natural polysaccharides cellulose and chitosan were employed for noncovalently wrapping around the purified SWCNTs to construct plysoaccharides-SWCNTs complexes. The complexes have improved aqueous dispersion and biocompatibility, thus they have promising applications as bio-scaffolds and medecine carriers.(2) In order to in vivo study the distribution, metabolism and toxicity of SWCNT-based carriers, near infrared fluorescent molecule and targeting molecule folid acid were covalently connect with chitosan functionalized SWCNTs, We found that the obtained products have good targeting properties for HeLa tumors in mice and show very low toxicity for liver, kidney and spleen.(3) Ion-exchange method was used to functionalizing SWCNTs with a sulfhydryl group terminated ionic liquid. Au nanoparticles were then decorated onto the resulted functionalized SWCNTs to get SWCNT-Au complex. Our research on this complex indicated it had the potential application as photo-thermal therapy reagent.