Quantitative detection of carbon nanotubes in biological samples by an original method based on microwave permittivity measurements

• Published in: Carbon (New York) 2015-01, Vol.81, p.535-545
• Main Authors: Bourdiol, Floriane, Dubuc, David, Grenier, Katia, Mouchet, Florence, Gauthier, Laury, Flahaut, Emmanuel
• Format: Article
• Language: English
• Subjects: Biological; Carbon; Carbon nanotubes; Complex permittivity; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Engineering Sciences; Exact sciences and technology; Exposure; Materials; Materials science; Microwaves; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotubes; Permittivity (dielectric function); Physics; Quantitative analysis
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2014.09.086

Due to their nanoscale, morphology, and chemical composition, the tracking and the quantitative analysis of carbon nanotubes (CNTs) in biological samples still represent huge challenges. A new technique for the quantitative and accurate detection of CNTs in various biological samples at different scales (whole organisms to organs) was developed using amphibian larvae exposed to double-walled CNTs (DWCNTs). This technique is based on the dielectric relaxation of ultra-low volume suspensions under a microwave electromagnetic field. CNT concentrations were consequently extracted from complex permittivity measurements at 5GHz, making possible to quantitatively assess the animal exposure to CNTs. Our results indicate a detection threshold of 0.02μg of DWCNTs, which is the lowest achieved in the literature to date.