Preparation of Carbon Nanotube Bioconjugates for Biomedical Applications

TL;DR

This paper reviews protocols for functionalizing and bioconjugating single wall carbon nanotubes (SWNTs) for biomedical uses like imaging, sensing, and drug delivery, emphasizing non-covalent methods that preserve optical properties.

Contribution

It summarizes and compares existing protocols for SWNT functionalization and bioconjugation, highlighting non-covalent methods suitable for biomedical applications.

Findings

Non-covalent functionalization retains optical properties

SWNTs can be conjugated with targeting ligands and radio labels

SWNTs can carry siRNA and chemotherapy drugs

Abstract

Biomedical applications of carbon nanotubes have attracted much attention in recent years. Here, we summarize our previously developed protocols for functionalization and bioconjugation of single wall carbon nanotubes (SWNTs) for various biomedical applications including biological imaging, sensing and drug delivery. Sonication of SWNTs in solutions of phospholipid-polyethylene glycol (PL-PEG) is our most commonly used protocol of SWNT functionalization. Compared to other frequently used covalent strategies, our non-covalent functionalization protocol largely retains the intrinsic optical properties of SWNTs, which are useful in various biological imaging and sensing applications. Functionalized SWNTs are conjugated with targeting ligands for specific cell labeling in vitro or tumor targeting in vivo. Radio labels are introduced for tracking and imaging of SWNTs in real time in vivo. Moreover, SWNTs can be conjugated with small interfering RNA (siRNA) or loaded with chemotherapy drugs for drug delivery. These procedures take various times ranging from one to five days.