Scavenger Receptor A1 Mediates the Uptake of Carboxylated and Pristine Multi-Walled Carbon Nanotubes Coated with Bovine Serum Albumin.

Previously, we noted that carboxylated multi-walled carbon nanotubes (cMWNTs) coated with Pluronic F-108 (PF108) bound to and were accumulated by macrophages, but that pristine multi-walled carbon nanotubes (pMWNTs) coated with PF108 were not (Wang et al., , , 677). Subsequent studies with Chinese hamster ovary (CHO) cells that overexpressed scavenger receptor A1 (SR-A1) and with macrophages derived from mice knocked out for SR-A1 provided evidence that SR-A1 was a receptor of PF108-cMWNTs (Wang et al.

The Importance of Evaluating the Lot-to-Lot Batch Consistency of Commercial Multi-Walled Carbon Nanotube Products.

The biological response of multi-walled carbon nanotubes (MWNTs) is related to their physicochemical properties and a thorough MWNT characterization should accompany an assessment of their biological activity, including their potential toxicity. Beyond characterizing the physicochemical properties of MWNTs from different sources or manufacturers, it is also important to characterize different production lots of the same MWNT product from the same vendor (i.e.

The impact of subcellular location on the near infrared-mediated thermal ablation of cells by targeted carbon nanotubes.

Single-walled carbon nanotubes (SWNTs) are used in the near infrared (NIR)-mediated thermal ablation of tumor cells because they efficiently convert absorbed NIR light into heat. Despite the therapeutic potential of SWNTs, there have been no published studies that directly quantify how many SWNTs need be associated with a cell to achieve a desired efficiency of killing, or what is the most efficient subcellular location of SWNTs for killing cells. Herein we measured dose response curves for the efficiency of killing correlated to the measured amounts of folate-targeted SWNTs that were either on the surface or within the vacuolar compartment of normal rat kidney cells.

Rapid detection of polyethylene glycol sonolysis upon functionalization of carbon nanomaterials.

Polyethylene glycol (PEG) and related polymers are often used in the functionalization of carbon nanomaterials in procedures that involve sonication. However, PEG is very sensitive to sonolytic degradation and PEG degradation products can be toxic to mammalian cells. Thus, it is imperative to assess potential PEG degradation to ensure that the final material does not contain undocumented contaminants that can introduce artifacts into experimental results.

A carbon nanotube-based Raman-imaging immunoassay for evaluating tumor targeting ligands.

Herein, we describe a versatile immunoassay that uses biotinylated single-walled carbon nanotubes (SWNTs) as a Raman label, avidin-biotin chemistry to link targeting ligands to the label, and confocal Raman microscopy to image whole cells. Using a breast tumor cell model, we demonstrate the usefulness of the method to assess membrane receptor/ligand systems by evaluating a monoclonal antibody, Her-66, known to target the Her2 receptors that are overexpressed on these cells. We present two-dimensional Raman images of the cellular distribution of the SWNT labels corresponding to the distribution of the Her2 receptors in different focal planes through the cell with validation of the method using immunofluorescence microscopy, demonstrating that the Her-66-SWNT complexes were targeted to Her2 cell receptors.