Researchers from the Department of Chemistry, Xiamen University, in China fabricate novel mesoporous silica composite nanoparticles (hm-SiO2(AlC4Pc)@Pd) for the co-delivery of a photosensitizer (PS) and photothermal reagent. The PS is tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) and the photothermal reagent is small Pd nanosheets. Together they present a dual carrier system that combines photodynamic therapy (PDT) with photothermal therapy (PTT) for enhanced results.

Nanocomposite advantages

The researchers find that the prepared hm-SiO2(AlC4Pc)@Pd nanocomposite has excellent biocompatibility, avid cell uptake, good singlet oxygen generation capacity and a high photothermal conversion efficiency. The small Pd nanosheets have a strong absorption in the near-infrared region (NIR), high photothermal conversion efficiency and excellent photothermal stability.

Matching absorption

The small Pd nanosheets and PS AlC4Pc have matching absorptions in the NIR region. As a result, the dual loaded nanocomposite synchronously exhibits photothermal and photodynamic effects under a single continuous wavelength irradiation. This greatly simplifies the experimental process and enhances the therapeutic efficiency.

Improved efficiency

In vitro results indicate that the cell-killing efficacy by a simultaneous PDT/PTT treatment using hm-SiO2(AlC4Pc)@Pd was higher than a PDT or PTT treatment alone after exposure to the 660 nm NIR laser. The results provide an avenue for the development of Pd-based multifunctional nanomaterials for NIR-induced cancer phototherapy.

More information about the research can be found in the journal Nanotechnology 25 285701.

Further reading

Simulating effective cancer hyperthermia using carbon nanotubes (Apr 2014)
Photothermal therapy eradicates tumours targeted by carbon nanotubes (Sep 2013)
Nanoparticle assembly on graphene oxide sheet strengthens fight against bacteria (July 2013)
Formulating dual-function nanoparticles for photodynamic and photothermal cancer therapy (Jan 2012)