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Increased heating efficiency and selective thermal ablation of malignant tissue with DNA-encased multiwalled carbon nanotubes.

Ghosh S, Dutta S, Gomes E, Carroll D, D'Agostino R, Olson J, Guthold M, Gmeiner WH - ACS Nano (2009)

Bottom Line: DNA-encasement resulted in a 3-fold reduction in the concentration of MWNTs required to impart a 10 degrees C temperature increase in bulk solution temperature.Nonmalignant tissues displayed no long-term damage from treatment.The results demonstrate that DNA-encased MWNTs are more efficient at converting nIR irradiation into heat compared to nonencased MWNTs and that DNA-encased MWNTs can be used safely and effectively for the selective thermal ablation of malignant tissue in vivo.

View Article: PubMed Central - PubMed

Affiliation: Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.

ABSTRACT
Nanoparticles, including multiwalled carbon nanotubes (MWNTs), strongly absorb near-infrared (nIR) radiation and efficiently convert absorbed energy to released heat which can be used for localized hyperthermia applications. We demonstrate for the first time that DNA-encasement increases heat emission following nIR irradiation of MWNTs, and DNA-encased MWNTs can be used to safely eradicate a tumor mass in vivo. Upon irradiation of DNA-encased MWNTs, heat is generated with a linear dependence on irradiation time and laser power. DNA-encasement resulted in a 3-fold reduction in the concentration of MWNTs required to impart a 10 degrees C temperature increase in bulk solution temperature. A single treatment consisting of intratumoral injection of MWNTs (100 microL of a 500 microg/mL solution) followed by laser irradiation at 1064 nm, 2.5 W/cm(2) completely eradicated PC3 xenograft tumors in 8/8 (100%) of nude mice. Tumors that received only MWNT injection or laser irradiation showed growth rates indistinguishable from nontreated control tumors. Nonmalignant tissues displayed no long-term damage from treatment. The results demonstrate that DNA-encased MWNTs are more efficient at converting nIR irradiation into heat compared to nonencased MWNTs and that DNA-encased MWNTs can be used safely and effectively for the selective thermal ablation of malignant tissue in vivo.

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Related in: MedlinePlus

SEM images for (a) non-DNA-encased MWNTs and (b) DNA-encased MWNTs. Upon DNA-encasement, the MWNTs are well-dispersed with few aggregates observed. AFM images (c,d) show well-dispersed DNA-encased MWNTs and also clearly show the curvature of MWNTs. Regions of MWNT broadening are likely sites of DNA localization. The diameter (determined from the height of the AFM images) and length distribution of DNA-encased MWNTs is shown in panels e and f.
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fig2: SEM images for (a) non-DNA-encased MWNTs and (b) DNA-encased MWNTs. Upon DNA-encasement, the MWNTs are well-dispersed with few aggregates observed. AFM images (c,d) show well-dispersed DNA-encased MWNTs and also clearly show the curvature of MWNTs. Regions of MWNT broadening are likely sites of DNA localization. The diameter (determined from the height of the AFM images) and length distribution of DNA-encased MWNTs is shown in panels e and f.

Mentions: AFM and SEM images of DNA-encased MWNTs were obtained in order to assess to what extent aqueous solutions of DNA-encased MWNTs were monodispersed and to assess the size distribution for MWNTs in DNA-encased samples. 2a shows a typical SEM image of non-DNA-encased MWNTs while DNA-encased MWNTs are shown in 2b. Non-DNA-encased MWNTs form aggregates while samples of DNA-encased MWNTs are well dispersed, with mainly single nanotubes. Regions of thickening of the MWNTs consistent with DNA binding were detected in AFM images for DNA-encased MWNTS. The presence of DNA on the MWNTs was verified by fluorescence quenching experiments (Supporting Information Figure S1).


Increased heating efficiency and selective thermal ablation of malignant tissue with DNA-encased multiwalled carbon nanotubes.

Ghosh S, Dutta S, Gomes E, Carroll D, D'Agostino R, Olson J, Guthold M, Gmeiner WH - ACS Nano (2009)

SEM images for (a) non-DNA-encased MWNTs and (b) DNA-encased MWNTs. Upon DNA-encasement, the MWNTs are well-dispersed with few aggregates observed. AFM images (c,d) show well-dispersed DNA-encased MWNTs and also clearly show the curvature of MWNTs. Regions of MWNT broadening are likely sites of DNA localization. The diameter (determined from the height of the AFM images) and length distribution of DNA-encased MWNTs is shown in panels e and f.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2748720&req=5

fig2: SEM images for (a) non-DNA-encased MWNTs and (b) DNA-encased MWNTs. Upon DNA-encasement, the MWNTs are well-dispersed with few aggregates observed. AFM images (c,d) show well-dispersed DNA-encased MWNTs and also clearly show the curvature of MWNTs. Regions of MWNT broadening are likely sites of DNA localization. The diameter (determined from the height of the AFM images) and length distribution of DNA-encased MWNTs is shown in panels e and f.
Mentions: AFM and SEM images of DNA-encased MWNTs were obtained in order to assess to what extent aqueous solutions of DNA-encased MWNTs were monodispersed and to assess the size distribution for MWNTs in DNA-encased samples. 2a shows a typical SEM image of non-DNA-encased MWNTs while DNA-encased MWNTs are shown in 2b. Non-DNA-encased MWNTs form aggregates while samples of DNA-encased MWNTs are well dispersed, with mainly single nanotubes. Regions of thickening of the MWNTs consistent with DNA binding were detected in AFM images for DNA-encased MWNTS. The presence of DNA on the MWNTs was verified by fluorescence quenching experiments (Supporting Information Figure S1).

Bottom Line: DNA-encasement resulted in a 3-fold reduction in the concentration of MWNTs required to impart a 10 degrees C temperature increase in bulk solution temperature.Nonmalignant tissues displayed no long-term damage from treatment.The results demonstrate that DNA-encased MWNTs are more efficient at converting nIR irradiation into heat compared to nonencased MWNTs and that DNA-encased MWNTs can be used safely and effectively for the selective thermal ablation of malignant tissue in vivo.

View Article: PubMed Central - PubMed

Affiliation: Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.

ABSTRACT
Nanoparticles, including multiwalled carbon nanotubes (MWNTs), strongly absorb near-infrared (nIR) radiation and efficiently convert absorbed energy to released heat which can be used for localized hyperthermia applications. We demonstrate for the first time that DNA-encasement increases heat emission following nIR irradiation of MWNTs, and DNA-encased MWNTs can be used to safely eradicate a tumor mass in vivo. Upon irradiation of DNA-encased MWNTs, heat is generated with a linear dependence on irradiation time and laser power. DNA-encasement resulted in a 3-fold reduction in the concentration of MWNTs required to impart a 10 degrees C temperature increase in bulk solution temperature. A single treatment consisting of intratumoral injection of MWNTs (100 microL of a 500 microg/mL solution) followed by laser irradiation at 1064 nm, 2.5 W/cm(2) completely eradicated PC3 xenograft tumors in 8/8 (100%) of nude mice. Tumors that received only MWNT injection or laser irradiation showed growth rates indistinguishable from nontreated control tumors. Nonmalignant tissues displayed no long-term damage from treatment. The results demonstrate that DNA-encased MWNTs are more efficient at converting nIR irradiation into heat compared to nonencased MWNTs and that DNA-encased MWNTs can be used safely and effectively for the selective thermal ablation of malignant tissue in vivo.

Show MeSH
Related in: MedlinePlus