Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Biodegradable luminescent porous silicon nanoparticles for in vivo applications


Nanomaterials that can circulate in the body hold great potential to diagnose and treat disease1,2,3,4. For such applications, it is important that the nanomaterials be harmlessly eliminated from the body in a reasonable period of time after they carry out their diagnostic or therapeutic function. Despite efforts to improve their targeting efficiency, significant quantities of systemically administered nanomaterials are cleared by the mononuclear phagocytic system before finding their targets, increasing the likelihood of unintended acute or chronic toxicity. However, there has been little effort to engineer the self-destruction of errant nanoparticles into non-toxic, systemically eliminated products. Here, we present luminescent porous silicon nanoparticles (LPSiNPs) that can carry a drug payload and of which the intrinsic near-infrared photoluminescence enables monitoring of both accumulation and degradation in vivo. Furthermore, in contrast to most optically active nanomaterials (carbon nanotubes, gold nanoparticles and quantum dots), LPSiNPs self-destruct in a mouse model into renally cleared components in a relatively short period of time with no evidence of toxicity. As a preliminary in vivo application, we demonstrate tumour imaging using dextran-coated LPSiNPs (D-LPSiNPs). These results demonstrate a new type of multifunctional nanostructure with a low-toxicity degradation pathway for in vivo applications.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Characterization of LPSiNPs.
Figure 2: Biocompatibility and biodegradability of LPSiNPs.
Figure 3: In vitro, in vivo and ex vivo fluorescence imaging with LPSiNPs.
Figure 4: Fluorescence images of tumours containing D-LPSiNPs.

Similar content being viewed by others


  1. Gao, X. H., Cui, Y. Y., Levenson, R. M., Chung, L. W. K. & Nie, S. M. In vivo cancer targeting and imaging with semiconductor quantum dots. Nature Biotech. 22, 969–976 (2004).

    Article  CAS  Google Scholar 

  2. Torchilin, V. P. Recent advances with liposomes as pharmaceutical carriers. Nature Rev. Drug Disc. 4, 145–160 (2005).

    Article  CAS  Google Scholar 

  3. Lee, J. H. et al. Artificially engineered magnetic nanoparticles for ultra-sensitive molecular imaging. Nature Med. 13, 95–99 (2007).

    Article  CAS  Google Scholar 

  4. Liu, Z. et al. Circulation and long-term fate of functionalized, biocompatible single-walled carbon nanotubes in mice probed by Raman spectroscopy. Proc. Natl Acad. Sci. USA 105, 1410–1415 (2008).

    Article  CAS  Google Scholar 

  5. Godefroo, S. et al. Classification and control of the origin of photoluminescence from Si nanocrystals. Nature Nanotech. 3, 174–178 (2008).

    Article  CAS  Google Scholar 

  6. Sengupta, S. et al. Temporal targeting of tumour cells and neovasculature with a nanoscale delivery system. Nature 436, 568–572 (2005).

    Article  CAS  Google Scholar 

  7. Farokhzad, O. C. et al. Targeted nanoparticle-aptamer bioconjugates for cancer chemotherapy in vivo. Proc. Natl Acad. Sci. USA 103, 6315–6320 (2006).

    Article  CAS  Google Scholar 

  8. Kim, D., Park, S., Lee, J. H., Jeong, Y. Y. & Jon, S. Antibiofouling polymer-coated gold nanoparticles as a contrast agent for in vivo X-ray computed tomography imaging. J. Am. Chem. Soc. 129, 7661–7665 (2007).

    Article  CAS  Google Scholar 

  9. Ballou, B., Lagerholm, B. C., Ernst, L. A., Bruchez, M. P. & Waggoner, A. S. Noninvasive imaging of quantum dots in mice. Bioconjugate Chem. 15, 79–86 (2004).

    Article  CAS  Google Scholar 

  10. Derfus, A. M., Chan, W. C. W. & Bhatia, S. N. Probing the cytotoxicity of semiconductor quantum dots. Nano Lett. 4, 11–18 (2004).

    Article  CAS  Google Scholar 

  11. Poland, C. A. et al. Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity in a pilot study. Nature Nanotech. 3, 423–428 (2008).

    Article  CAS  Google Scholar 

  12. Choi, H. S. et al. Renal clearance of quantum dots. Nature Biotech. 25, 1165–1170 (2007).

    Article  CAS  Google Scholar 

  13. Bayliss, S. C., Heald, R., Fletcher, D. I. & Buckberry, L. D. The culture of mammalian cells on nanostructured silicon. Adv. Mater. 11, 318–321 (1999).

    Article  CAS  Google Scholar 

  14. Canham, L. T. Bioactive silicon structure fabrication through nanoetching techniques. Adv. Mater. 7, 1033–1037 (1995).

    Article  CAS  Google Scholar 

  15. Cunin, F. et al. Biomolecular screening with encoded porous-silicon photonic crystals. Nature Mater. 1, 39–41 (2002).

    Article  CAS  Google Scholar 

  16. Salonen, J., Kaukonen, A. M., Hirvonen, J. & Lehto, V.-P. Mesoporous silicon in drug delivery applications. J. Pharm. Sci. 97, 632–653 (2008).

    Article  CAS  Google Scholar 

  17. Canham, L. T. Silicon quantum wire array fabrication by electrochemical and chemical dissolution of wafers. Appl. Phys. Lett. 57, 1046–1048 (1990).

    Article  CAS  Google Scholar 

  18. Heinrich, J. L., Curtis, C. L., Credo, G. M., Kavanagh, K. L. & Sailor, M. J. Luminescent colloidal silicon suspensions from porous silicon. Science 255, 66–68 (1992).

    Article  CAS  Google Scholar 

  19. Wilson, W. L., Szajowski, P. F. & Brus, L. E. Quantum confinement in size-selected surface-oxidized silicon nanocrystals. Science 262, 1242–1244 (1993).

    Article  CAS  Google Scholar 

  20. Mangolini, L. & Kortshagen, U. Plasma-assisted synthesis of silicon nanocrystal inks. Adv. Mater. 19, 2513–2519 (2007).

    Article  CAS  Google Scholar 

  21. Wang, L., Reipa, V. & Blasic, J. Silicon nanoparticles as a luminescent label to DNA. Bioconjugate Chem. 15, 409–412 (2004).

    Article  CAS  Google Scholar 

  22. Li, Z. F. & Ruckenstein, E. Water-soluble poly(acrylic acid) grafted luminescent silicon nanoparticles and their use as fluorescent biological staining labels. Nano Lett. 4, 1463–1467 (2004).

    Article  CAS  Google Scholar 

  23. Popplewell, J. F. et al. Kinetics of uptake and elimination of silicic acid by a human subject: A novel application of 32Si and accelerator mass spectrometry. J. Inorg. Biochem. 69, 177–180 (1998).

    Article  CAS  Google Scholar 

  24. Weissleder, R. A clearer vision for in vivo imaging. Nature Biotech. 19, 316–317 (2001).

    Article  CAS  Google Scholar 

  25. Piryutko, M. M. The solubility of silicic acid in salt solutions. Russ. Chem. Bull. 8, 355–360 (1959).

    Article  Google Scholar 

  26. Minotti, G., Menna, P., Salvatorelli, E., Cairo, G. & Gianni, L. Anthracyclines: Molecular advances and pharmacologic developments in antitumor activity and cardiotoxicity. Pharmacol. Rev. 56, 185–229 (2004).

    Article  CAS  Google Scholar 

  27. Wunderbaldinger, P., Josephson, L. & Weissleder, R. Tat peptide directs enhanced clearance and hepatic permeability of magnetic nanoparticles. Bioconjugate Chem. 13, 264–268 (2002).

    Article  CAS  Google Scholar 

  28. Slowing, I., Trewyn, B. G. & Lin, V. S.-Y. Effect of surface functionalization of MCM-41-type mesoporous silica nanoparticles on the endocytosis by human cancer cells. J. Am. Chem. Soc. 128, 14792–14793 (2006).

    Article  CAS  Google Scholar 

  29. Kim, S. et al. Near-infrared fluorescent type II quantum dots for sentinel lymph node mapping. Nature Biotech. 22, 93–97 (2003).

    Article  Google Scholar 

  30. Suh, K. Y. et al. Characterization of chemisorbed hyaluronic acid directly immobilized on solid substrates. J. Biomed. Mater. Res. B 15, 292–298 (2006).

    Google Scholar 

Download references


This work was supported by the National Cancer Institute of the National Institutes of Health through grant numbers U54 CA 119335 (UCSD CCNE), 5-R01-CA124427 (BRP) and U54 CA119349 (MIT CCNE). M.J.S., S.N.B. and E.R. are members of the Moores UCSD Cancer Center and the UCSD NanoTUMOR Center under which this work was conducted and supported by the NIH/NCI grant. J.-H.P. thanks the Korea Science and Engineering Foundation (KOSEF) for a Graduate Study Abroad Scholarship. The authors thank Melanie L. Oakes in the Hitachi Chemical Research for assistance with SEM analysis, Edward Monosov in the Burnham Institute for Medical Research for assistance with confocal and multi-photon microscopy and Nissi Varki of the Moores UCSD Cancer Center for toxicity examination of the histology samples.

Author information

Authors and Affiliations



J.-H.P., L.G. and M.J.S. conceived and designed the research. J.-H.P. and L.G. carried out the experiments. J.-H.P., L.G., G.v.M., E.R., S.N.B. and M.J.S. analysed the data. J.-H.P. and M.J.S. wrote the manuscript.

Corresponding author

Correspondence to Michael J. Sailor.

Supplementary information

Supplementary Information

Supplementary Information (PDF 1265 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Park, JH., Gu, L., von Maltzahn, G. et al. Biodegradable luminescent porous silicon nanoparticles for in vivo applications. Nature Mater 8, 331–336 (2009).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing