Biological Applications of Polyaniline Nanofibers

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

Humacao. Puerto Rico

Congreso; PAN-AMERICAN ADVANCED STUDIES INSTITUTE (PASI); 2010

PAN-AMERICAN ADVANCED STUDIES INSTITUTE (PASI)

Polyaniline nanoparticles are small objects which are suitable as multifunction vectors for insertion of bioactive principles into living cells. 1 Additionally, the optical properties of the particles could be used with profit in Near Infrared (NIR) photothermal therapy and/or tomography. Since polyaniline has a broad absorption band, due to free carrier absorption, with a maximum at ca. 800 nm it absorbs in the NIR range. Living tissue absorbs little light between 700 and 1200 nm. Therefore, light in this region could penetrate several centimeters to be absorbed by a suitable susceptor, such as polyaniline. Polyaniline nanoparticles can be easily synthesized by nucleation and growth polymerization, 2 using poly(vinylpyrrolidone) 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 effect of laser light. To follow the intake of PANI nanofibers into the cells, we used UV-vis spectroscopy. 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. Irradiation of the cells with NIR light produce cell death.