Systemic Delivery of Sirna-Based Therapeutics Using Single-Walled Carbon Nanotubes

Background: Carbon nanotubes (CNTs) are potential candidates for drug, antigen and nucleic acid delivery vehicle in nanomedicine. The large surface of CNTs provides structural advantages and allows loading of functional groups or therapeutics such as nucleic acid, drugs and proteins. Aim: Our study is to deliver siRNA to cells using single walled carbon nanotube (SWNT) to achieve gene silencing effect. Methods: SWNT was functionalized by dissolving 1 mg of HiPCo SWNTs and 5 mg of PL-PEG-NH or PL-PEG-maleimide in 5 mL of water, sonicated for 60 min at room temperature and centrifuged for 6 h. The supernatant were collected and measured their concentration at 808 nm by ultraviolet-VIS-NIR spectrometer. The resulted noncovalent functionalized SWNTs were further conjugated with a 5′-thiolated siRNA against GFP (siGFP) and RFP (siRFP). In vitro silencing of GFP and RFP expression by SWNT-siRNA were evaluated in stable expression cell lines by fluorescence spectroscopy. Results: A range of 50%–80% GFP expressio...