Mechanochemically activated doxorubicin nanoparticles in combination with 40 MHz frequency irradiation on A-549 lung carcinoma cells.

Targeting of mechanochemically activated doxorubicin (MA DOXO) nanoparticles, conventional doxorubicin, and electromagnetic irradiation (EMI) at A-549 lung carcinoma cells in vitro was investigated. Conventional DOXO was micronized using an input energy of 20 W/g for 5 min resulting in positively charged MA DOXO particles 10 times smaller than conventional DOXO. Mechanochemical activation gives rise to additional free quinone radicals. High performance liquid chromatograph analyses demonstrate that conventional and MA DOXO are quantitatively similar. Tumor cells were exposed to 40 MHz electromagnetic irradiation at a power density of 2 W/cm2. The lethal dose LD50 values of MA DOXO were 5 times greater than conventional doxorubicin. MA DOXO in combination with EMI at 37 degrees C demonstrates improved drug delivery to A-549 human lung carcinoma and greater cell kill than does conventional DOXO.