CONDUCTING POLYMER NANOPARTICLE MEDIATED PHOTOHERMALTUMOR THERAPY

MOLINA M.A.; RIVAROLA C.; YSLAS E. I.; RIVAROLA V; BARBERO C

BIOCELL

INST HISTOL EMBRIOL-CONICET

Lugar: Argentina; Año: 2010 vol. 34 p. 65 - 65

0327-9545

Since living tissue absorbs little light between ca. 700 and 1200 nm, light in this wavelength region could penetrate several centimeters into de the body to be absorbed by a suitable mediator. Gold nanoparticles and carbon nanotubes have been used in photothermal tumor therapy. Conducting polymer (e.g. Polyanniline) nanoparticles have a broad absorption band, due to free carrier absorption, with a maximum in the NIR range. Polyaniline nanoparticles can be easily synthesized by nucleation and growth polymerization, using poly(vinylpyrrolidone) (PVP) as stabilizer. The stabilized PANI nanoparticles form a stable suspension at physiological pH. Tests using a NIR (780 nm, 100 mW) laser show a clear photothermal heating. The intake of PANI nanoparticles into the cells was followed by UV-vis spectroscopy, using the characteristic spectra of PANI. Then immobilized cells are incubated in PBS buffer containing the dispersed nanoparticles. It is found that, below a concentration threshold, PANI nanoparticles are innocuous to the cells in the dark. It was found that the cytotoxicity of the particle depends on the molecular weight of the PVP used. Irradiation of the cells with NIR light produces cell death. It is envisaged that, being made of organic polymers, the nanoparticles could be more easily biodegraded in the body than carbon nanotubes or gold nanoparticles.