Smart polyaniline nanoparticles with thermal and photothermal sensitivity.

摘要: Conductive polyaniline nanoparticles (PANI NPs) are synthesized by oxidation of aniline with persulfate in acid media, the presence polymeric stabilizers: polyvinilpyrrolidone (PVP), poly(N-isopropylacrylamide) (PNIPAM), and hydroxylpropylcellulose (HPC). It is observed that size obtained depends on stabilizer used, suggesting a mechanism where aggregation molecules arrested adsorption stabilizer. Indeed, polymerization mixture two polymers having different stabilizing capacity (PVP PNIPAM) allows tuning nanoparticles. Stabilization biocompatible PVP, HPC PNIPAM use nanoparticle dispersions biological applications. The stabilized thermosensitive (PNIPAM HPC) aggregate when temperature exceeds phase transition (coil to globule) each (Tpt = 32 °C for or Tpt = 42 HPC). This result suggests an extended coil form necessary avoid aggregation. reversibly restored lowered below Tpt. In way, effect could be used separate from soluble contaminants. On other hand, PANI NPs PVP unaffected change. UV-visible spectroscopy measurements show dispersion changes their spectra pH external solution, small can easily penetrate shell. Near infrared radiation absorbed causing increase which induces collapse polymer shell NPs. reveals it possible locally heat nanoparticles, phenomenon destroy tumor cells cancer therapy dissolve protein aggregates neurodegenerative diseases (e.g. Alzheimer). Moreover, long range control modulate residence inside tissues.