In vivo biodistribution and urinary excretion of mesoporous silica nanoparticles: effects of particle size and PEGylation

Small. 2011 Jan 17;7(2):271-80. doi: 10.1002/smll.201001459. Epub 2010 Dec 10.


The in vivo biodistribution and urinary excretion of spherical mesoporous silica nanoparticles (MSNs) are evaluated by tail-vein injection in ICR mice, and the effects of the particle size and PEGylation are investigated. The results indicate that both MSNs and PEGylated MSNs of different particle sizes (80-360 nm) distribute mainly in the liver and spleen, a minority of them in the lungs, and a few in the kidney and heart. The PEGylated MSNs of smaller particle size escape more easily from capture by liver, spleen, and lung tissues, possess longer blood-circulation lifetime, and are more slowly biodegraded and correspondingly have a lower excreted amount of degradation products in the urine. Neither MSNs nor PEGylated MSNs cause tissue toxicity after 1 month in vivo.

MeSH terms

  • Animals
  • Mice
  • Mice, Inbred ICR
  • Nanoparticles / chemistry*
  • Particle Size
  • Polyethylene Glycols / chemistry*
  • Porosity
  • Silicon Dioxide / chemistry*


  • Polyethylene Glycols
  • Silicon Dioxide