Induction of Apoptosis in Cancer Cells at Low Silver Nanoparticle Concentrations using Chitosan Nanocarrier
In this clinical study, published in the journal ACS Applied Material & Interfaces in January 2011, researchers used a chitosan-based carrier to deliver silver nanoparticles to human colon cancer cells.
According to the study authors, “Cell viability assay demonstrated that the concentration of Ag NPs required to reduce the viability of HT 29 cells by 50% was 0.33 µg mL-1, much less than in previously reported data.” In other words, the researchers found that it only took a concentration of 3.3 ppm silver nanoparticles to reduce cancer cells by 50% in vitro.
The researchers further stated, “The increased production of intracellular ROS due to Ag-CS NCs treatment indicated that the oxidative stress could augment the induction of apoptosis in HT 29 cells in addition to classical caspase signaling pathway. The use of significantly low concentration of Ag NPs impregnated in chitosan nanocarrier is a much superior approach in comparison to the use of free Ag NPs in cancer therapy.” In other words, the silver nanoparticles induced reactive oxygen species inside the cancer cells, resulting in an activation of the cellular signaling pathway that controls apopotosis (cellular suicide), and thereby triggering the cancer cells to self-destruct.
