Oncology Applications

  • Most chemotherapeutics are low molecular weight molecules with poor solubility that are easily excreted requiring higher concentrations
  • Most chemotherapeutics are not selective resulting in nonspecific distribution throughout the body including healthy tissues
  • As a result toxicity is unavoidable
  • Nanoparticles address these issues
Nanoparticles Exploit Abnormal Tumor Vascular Architecture
  • Tumors require blood supply and newly formed tumor vessels are usually abnormal in architecture
  • Nanoparticle strategy is to target tumors by exploiting abnormalities of tumor vasculature and the local tumor microenviroment
    • Aberrant vascular architecture
    • Extensive production of vascular permeability factors stimulating extravasation within tumor tissues
    • Lack of lymphatic drainage
Enhanced Perfusion Retention
  Nanoparticles do not penetrate through tight endothelial 
  junctions of normal blood vessels resulting in a longer 
  plasma half-life

  Nanoparticles can selectively extravasate into tumor tissues 
  due to abnormal (leaky) vascular nature

  Enhanced Perfusion Retention (EPR) effect is important for 
  nanoparticle delivery to tumor tissue

  Concentrations of particles build up in tumors several folds 
  higher than that of the plasma - increases residence time of 
  the chemo-agent at site of action

  This selective high local concentration of nano-anticancer 
  drugs in tumor tissues provides superior in therapeutic 
  effect while reducing side effect

Safe Sustained Drug Delivery using Nanoporous Silicon Particles