Loading carbon nanotubes with viscous fluids and nanoparticles - A simpler approach

Abstract

Carbon nanotubes have demonstrated exceptional properties enabling them to be considered for applications in drug delivery and other biologically important fields. The emphasis of the current drug delivery research with carbon nanotubes focuses on surface functionalization of the nanotubes and attachment of biomolecules, while leaving the inner void unmodified and mostly empty. Here, we report a simple, cost effective, and scalable method for filling and sealing carbon nanotubes with viscous solutions of biomaterials and nanoparticles (10 to 100 nm). The loading of nanotubes was achieved by optimal centrifugation in the presence of the viscous solution containing nanoparticles. This novel method was found to be effective for loading nanoparticles from 10 nm up to 40 nm in diameter, while increased sedimentation of particles larger than 40 nm resulted in reduced loading efficiency. Scanning electron microscopy and confocal laser scanning microscopy were used to analyze to confirm and image the loading of carbon nanotubes. This method could have immediate exciting applications in drug delivery especially for subcutaneous and slow release formulations. © 2007 Springer-Verlag.