Contrast-Enhanced Multispectal Upconversion Fluorescence Analysis for High-Resolution in-vivo Deep Tissue Imaging

Lanthanide-doped upconversion nanoparticles which can convert near-infrared lights to visible lights have attracted growing interest because of their great potentials in fluorescence imaging. Upconversion fluorescence imaging technique with excitation in the near-infrared (NIR) region has been used for imaging of biological cells and tissues. However, improving the detection sensitivity and decreasing the absorption and scattering in biological tissues are as yet unresolved problems. In this present study, a novel NIR-reflected multispectral imaging system was developed for upconversion fluorescent imaging in small animals. Based on this system, we have obtained the high contrast images without the autofluorescence when biocompatible UCPs were injected near the body surface or deeply into the tissue. Furthermore, we have extracted respective spectra of the upconversion fluorescence and relatively quantify the fluorescence intensity with the multispectral analysis. To our knowledge, this is the first time to analyze and quantify the upconversion fluorescence in the small animal imaging.

• Lijiang Wang
• Wei Wang
• Yuhong Xu

• Multispectral imaging
• near-infrared
• upconversion fluorescence imaging
• upconversion nanoparticles.

[1] S.A. Hilderbrand, and R.Weissleder, " Near-infrared fluorescence:
application to in vivo molecular imaging," Curr. Opin. Chem. Biol. , vol.
14, pp.71-79, Feb. 2010.
[2] J.H. Rao , A. Dragulescu-Andrasi, and H.Q.Yao, "Fluorescence imaging
in vivo: recent advances,"Curr .Opin. Biotechnol., vol. 18, pp17-25,
Feb. 2007.
[3] S.L. Luo, E.L. Zhang, Y.P. Su, T.M. Cheng, and C.M. Shi, " A review
of NIR dyes in cancer targeting and imaging." Biomaterials, vol.32, pp.
7127-7138, Oct. 2011.
[4] E. Baggaley, J.A. Weinstein, and J.A. Gareth Williams, " Lighting the
way to see inside the live cell with luminescent transition metal
complexes ," Coordin. Chem. Rev., vol. 256, pp. 1762-1785, Aug. 2012.
[5] E. Cassette, M. Helle, L. Bezdetnaya, F. Marchal, B. Dubertret, and T.
Pons, " Design of new quantum dot materials for deep tissue infrared
imaging ," Adv. Drug Delivery Rev., in press.
[6] A.M. Smith, H.W. Duan, A.M. Mohs, and S.M. Nie, "Bioconjugated
quantum dots for in vivo molecular and cellular imaging ," Adv. Drug
Delivery Rev., vol. 60, pp. 1226-1240, Aug.2008.
[7] K. Schenke-Layland, I. Riemann, O. Damour , U.A. Stock, and K.
Konig, "Two-photon microscopesand in vivo multiphoton tomographs -
powerful diagnostic tools for tissue engineering and drug delivery." Adv.
Drug Delivery Rev., vol. 58, pp. 878-896, Sep. 2006.
[8] J.V. Frangioni, " In vivo near-infrared fluorescence imaging ," Curr.
Opin. Chem. Biol., vol.7, pp. 626-634, Oct. 2003.
[9] H.S. Mader, P. Kele, S.M. Saleh, and O.S. Wolfbeis, "Upconverting
luminescent nanoparticles for use in bioconjugation and bioimaging ,"
Curr. Opin. Chem. Biol., vol.14, pp. 582-596, Oct. 2010.
[10] D.K. Chatterjee , A.J.Rufaihah, and Y.Zhang, " Upconversion
fluorescence imaging of cells and small animals using lanthanide doped
nanocrystals," Biomaterials, vol. 29, pp.937-943, Mar. 2008.
[11] A.J. Rufaihah, and Y. Zhang, " Biocompatibility of silica coated NaYF4
upconversion fluorescent nanocrystals," Biomaterials, vol.29, pp. 4122-
4128, Oct.2008.
[12] M. Wang, G.Abbineni, A. Clevenger, C. Mao, and S. Xu,
"Upconversion nanoparticles: synthesis, surface modification and
biological applications ," Nanomedicine: N.B.M., vol.7, pp.710-729,
Dec. 2011.