Michelle Hung, Ping Li, Wei Liu and Yanlian Yang
St. Mark's School, Southborough, Massachusetts, MA, USA
Nano-particulate drugs hold great promise of improving drug efficacy because of their enhanced solubility, prolonged retention time, and higher bioavailability with tissues or cells. Generally, these nanoparticles are encapsulated to keep them well dispersed with specific particle size in the manufacturing process. The additional advantage of encapsulation is that a rationally selected coating agent may tailor the pharmacokinetics and control the release of therapeutic nanoparticles in the targeted tissue, simultaneously reducing the toxicity and side effects of drugs. Here we report paclitaxel nanoparticles (PTX-NPs) encapsulated by metal-polyphenol layer, produced by one-step aerosol spray method. PTX-NPs act as a template, which enables in-situ formation of a membrane of coordination complexes of polyphenol tannic acid and Fe(III) in the solution. The produced PTX-NPs with metal-polyphenol encapsulation (PTX-C) are stable in water and have pH responsiveness for releasing. To investigate the safety and effectiveness of the PTX-C, an in vitro drug release and cytotoxicity assay is performed on human breast cancer cell line (MCF-7). The IC50 of PTX-C is lower than that of PTX-NPs and ABI-007. Cellular uptake and distribution of Rhodamine B labelled PTX-C in MCF-7 cells indicates that PTX-C could be endocytosed by cells and localized in lysosomes. A control experiment proved that TA/Fe(III) complex is nearly non-cytotoxic, evidencing the potential of PTX-C for cancer therapies.
Keywords: Antitumor nanodrugs, metal ions/polyphenol complex, paclitaxel, aerosol spraying process, MCF-7.