Abstract

In neuroscience, fluorescence labeled two-photon microscopy is a promising tool to visualize ex vivo and in vivo tissue morphology, and track dynamic neural activities. Specific and highly photostable fluorescent probes are required in this technology. However, most fluorescent proteins and organic fluorophores suffer from photobleaching, so they are not suitable for long-term imaging and observation. To overcome this problem, we utilize tetraphenylethene-triphenylphosphonium (TPE-TPP), which possesses aggregation-induced emission (AIE) and two-photon fluorescence characteristics, for neuroimaging. The unique AIE feature of TPE-TPP makes its nanoaggregates resistant to photobleaching, which is useful to track neural cells and brain-microglia for a long period of time. Two-photon fluorescence of TPE-TPP facilitates its application in deep in vivo neuroimaging, as demonstrated in the present paper.

© 2015 Optical Society of America

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2014 (2)

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

2013 (6)

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
[Crossref]

Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
[Crossref]

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

2012 (3)

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

2010 (1)

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

2009 (2)

Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
[Crossref]

D. Kobat, M. E. Durst, N. Nishimura, A. W. Wong, C. B. Schaffer, and C. Xu, “Deep tissue multiphoton microscopy using longer wavelength excitation,” Opt. Express 17(16), 13354–13364 (2009).
[Crossref] [PubMed]

2008 (2)

G. S. He, L. S. Tan, Q. Zheng, and P. N. Prasad, “Multiphoton absorbing materials: Molecular designs, characterizations, and applications,” Chem. Rev. 108(4), 1245–1330 (2008).
[Crossref] [PubMed]

X. Yang and L. V. Wang, “Monkey brain cortex imaging by photoacoustic tomography,” J. Biomed. Opt. 13(4), 044009 (2008).
[Crossref] [PubMed]

2005 (1)

2003 (2)

R. Weissleder and V. Ntziachristos, “Shedding light onto live molecular targets,” Nat. Med. 9(1), 123–128 (2003).
[Crossref] [PubMed]

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

2002 (1)

T. S. Chen, S. Q. Zeng, Q. M. Luo, Z. H. Zhang, and W. Zhou, “High-order photobleaching of green fluorescent protein inside live cells in two-photon excitation microscopy,” Biochem. Biophys. Res. Commun. 291(5), 1272–1275 (2002).
[Crossref] [PubMed]

2001 (3)

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

F. Helmchen, M. S. Fee, D. W. Tank, and W. Denk, “A miniature head-mounted two-photon microscope. High-resolution brain imaging in freely moving animals,” Neuron 31(6), 903–912 (2001).
[Crossref] [PubMed]

2000 (1)

Y. G. Meng, J. Liang, W. L. Wong, and V. Chisholm, “Green fluorescent protein as a second selectable marker for selection of high producing clones from transfected CHO cells,” Gene 242(1-2), 201–207 (2000).
[Crossref] [PubMed]

1999 (2)

M. Maletic-Savatic, R. Malinow, and K. Svoboda, “Rapid dendritic morphogenesis in CA1 hippocampal dendrites induced by synaptic activity,” Science 283(5409), 1923–1927 (1999).
[Crossref] [PubMed]

J. White and E. Stelzer, “Photobleaching GFP reveals protein dynamics inside live cells,” Trends Cell Biol. 9(2), 61–65 (1999).
[Crossref] [PubMed]

Bastien, D.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Boas, D. A.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Cai, F. H.

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Chen, G. D.

Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
[Crossref]

Chen, H.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Chen, S.

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

Chen, S. C.

Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
[Crossref]

Chen, T. S.

T. S. Chen, S. Q. Zeng, Q. M. Luo, Z. H. Zhang, and W. Zhou, “High-order photobleaching of green fluorescent protein inside live cells in two-photon excitation microscopy,” Biochem. Biophys. Res. Commun. 291(5), 1272–1275 (2002).
[Crossref] [PubMed]

Chen, X.

Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
[Crossref]

Cheng, H.

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

Cheng, L.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Cheng, X.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Chisholm, V.

Y. G. Meng, J. Liang, W. L. Wong, and V. Chisholm, “Green fluorescent protein as a second selectable marker for selection of high producing clones from transfected CHO cells,” Gene 242(1-2), 201–207 (2000).
[Crossref] [PubMed]

Chui, Q. X.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

Chung, S. J.

Clark, C. G.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

Cui, Y. P.

Denk, W.

F. Helmchen, M. S. Fee, D. W. Tank, and W. Denk, “A miniature head-mounted two-photon microscope. High-resolution brain imaging in freely moving animals,” Neuron 31(6), 903–912 (2001).
[Crossref] [PubMed]

Ding, D.

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

Durst, M. E.

Fee, M. S.

F. Helmchen, M. S. Fee, D. W. Tank, and W. Denk, “A miniature head-mounted two-photon microscope. High-resolution brain imaging in freely moving animals,” Neuron 31(6), 903–912 (2001).
[Crossref] [PubMed]

Feng, G.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

Gallagher, A.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Gaudette, T.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Geng, J.

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Gong, H.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

He, G. S.

He, H.

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

He, S.

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

He, S. L.

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

Helmchen, F.

F. Helmchen, M. S. Fee, D. W. Tank, and W. Denk, “A miniature head-mounted two-photon microscope. High-resolution brain imaging in freely moving animals,” Neuron 31(6), 903–912 (2001).
[Crossref] [PubMed]

Hong, Y.

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

Horton, N. G.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

Hu, M. L.

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Hu, Y.

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

Kobat, D.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

D. Kobat, M. E. Durst, N. Nishimura, A. W. Wong, C. B. Schaffer, and C. Xu, “Deep tissue multiphoton microscopy using longer wavelength excitation,” Opt. Express 17(16), 13354–13364 (2009).
[Crossref] [PubMed]

Ku, G.

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Kwok, H. S.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Lam, J. W. Y.

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Lassonde, M.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Leong, D. T.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

Lepore, F.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Leung, C. W. T.

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

Li, A.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

Li, K.

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Liang, J.

Y. G. Meng, J. Liang, W. L. Wong, and V. Chisholm, “Green fluorescent protein as a second selectable marker for selection of high producing clones from transfected CHO cells,” Gene 242(1-2), 201–207 (2000).
[Crossref] [PubMed]

Lin, T. C.

Liu, B.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

Liu, H.

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Liu, J.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

Liu, Q.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

Liu, R.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Liu, X. L.

Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
[Crossref]

Liu, Y.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Lu, C. G.

Luo, J.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Luo, Q.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

Luo, Q. M.

T. S. Chen, S. Q. Zeng, Q. M. Luo, Z. H. Zhang, and W. Zhou, “High-order photobleaching of green fluorescent protein inside live cells in two-photon excitation microscopy,” Biochem. Biophys. Res. Commun. 291(5), 1272–1275 (2002).
[Crossref] [PubMed]

Lv, X. H.

Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
[Crossref]

Ma, E.

Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
[Crossref]

Maletic-Savatic, M.

M. Maletic-Savatic, R. Malinow, and K. Svoboda, “Rapid dendritic morphogenesis in CA1 hippocampal dendrites induced by synaptic activity,” Science 283(5409), 1923–1927 (1999).
[Crossref] [PubMed]

Malinow, R.

M. Maletic-Savatic, R. Malinow, and K. Svoboda, “Rapid dendritic morphogenesis in CA1 hippocampal dendrites induced by synaptic activity,” Science 283(5409), 1923–1927 (1999).
[Crossref] [PubMed]

Mandeville, J. B.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Marota, J. J. A.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Meng, Y. G.

Y. G. Meng, J. Liang, W. L. Wong, and V. Chisholm, “Green fluorescent protein as a second selectable marker for selection of high producing clones from transfected CHO cells,” Gene 242(1-2), 201–207 (2000).
[Crossref] [PubMed]

Nishimura, N.

Ntziachristos, V.

R. Weissleder and V. Ntziachristos, “Shedding light onto live molecular targets,” Nat. Med. 9(1), 123–128 (2003).
[Crossref] [PubMed]

Pang, Y.

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Peng, L.

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Prasad, P. N.

Qian, J.

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
[Crossref]

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Qin, A.

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

Qin, A. J.

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

Qin, W.

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
[Crossref]

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

Qiu, C.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Schaffer, C. B.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

D. Kobat, M. E. Durst, N. Nishimura, A. W. Wong, C. B. Schaffer, and C. Xu, “Deep tissue multiphoton microscopy using longer wavelength excitation,” Opt. Express 17(16), 13354–13364 (2009).
[Crossref] [PubMed]

Stelzer, E.

J. White and E. Stelzer, “Photobleaching GFP reveals protein dynamics inside live cells,” Trends Cell Biol. 9(2), 61–65 (1999).
[Crossref] [PubMed]

Stoica, G.

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Strangman, G.

D. A. Boas, T. Gaudette, G. Strangman, X. Cheng, J. J. A. Marota, and J. B. Mandeville, “The accuracy of near infrared spectroscopy and imaging during focal changes in cerebral hemodynamics,” Neuroimage 13(1), 76–90 (2001).
[Crossref] [PubMed]

Svoboda, K.

M. Maletic-Savatic, R. Malinow, and K. Svoboda, “Rapid dendritic morphogenesis in CA1 hippocampal dendrites induced by synaptic activity,” Science 283(5409), 1923–1927 (1999).
[Crossref] [PubMed]

Tan, L. S.

G. S. He, L. S. Tan, Q. Zheng, and P. N. Prasad, “Multiphoton absorbing materials: Molecular designs, characterizations, and applications,” Chem. Rev. 108(4), 1245–1330 (2008).
[Crossref] [PubMed]

Tang, B. Z.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
[Crossref]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

C. W. T. Leung, Y. Hong, S. Chen, E. Zhao, J. W. Y. Lam, and B. Z. Tang, “A photostable AIE luminogen for specific mitochondrial imaging and tracking,” J. Am. Chem. Soc. 135(1), 62–65 (2013).
[Crossref] [PubMed]

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
[Crossref]

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Tang, C.

Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
[Crossref]

Tank, D. W.

F. Helmchen, M. S. Fee, D. W. Tank, and W. Denk, “A miniature head-mounted two-photon microscope. High-resolution brain imaging in freely moving animals,” Neuron 31(6), 903–912 (2001).
[Crossref] [PubMed]

Tay, C. Y.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

Thériault, M.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Tomczak, N.

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
[Crossref] [PubMed]

K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
[Crossref] [PubMed]

Tremblay, J.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Vannasing, P.

D. Bastien, A. Gallagher, J. Tremblay, P. Vannasing, M. Thériault, M. Lassonde, and F. Lepore, “Specific functional asymmetries of the human visual cortex revealed by functional near-infrared spectroscopy,” Brain Res. 1431, 62–68 (2012).
[Crossref] [PubMed]

Wang, D.

D. Wang, J. Qian, W. Qin, A. Qin, B. Z. Tang, and S. He, “Biocompatible and photostable AIE dots with red emission for in vivo two-photon bioimaging,” Sci Rep 4, 4279 (2014).
[PubMed]

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Wang, K.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

Wang, L. V.

X. Yang and L. V. Wang, “Monkey brain cortex imaging by photoacoustic tomography,” J. Biomed. Opt. 13(4), 044009 (2008).
[Crossref] [PubMed]

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Wang, Q.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

Wang, X.

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Weissleder, R.

R. Weissleder and V. Ntziachristos, “Shedding light onto live molecular targets,” Nat. Med. 9(1), 123–128 (2003).
[Crossref] [PubMed]

White, J.

J. White and E. Stelzer, “Photobleaching GFP reveals protein dynamics inside live cells,” Trends Cell Biol. 9(2), 61–65 (1999).
[Crossref] [PubMed]

Wise, F. W.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

Wong, A. W.

Wong, W. L.

Y. G. Meng, J. Liang, W. L. Wong, and V. Chisholm, “Green fluorescent protein as a second selectable marker for selection of high producing clones from transfected CHO cells,” Gene 242(1-2), 201–207 (2000).
[Crossref] [PubMed]

Wu, J.

A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
[Crossref] [PubMed]

Wu, Y. X.

Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
[Crossref]

Xi, W.

J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Xie, X.

X. Wang, Y. Pang, G. Ku, X. Xie, G. Stoica, and L. V. Wang, “Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain,” Nat. Biotechnol. 21(7), 803–806 (2003).
[Crossref] [PubMed]

Xie, Z.

J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
[Crossref] [PubMed]

Xu, C.

N. G. Horton, K. Wang, D. Kobat, C. G. Clark, F. W. Wise, C. B. Schaffer, and C. Xu, “In vivo three-photon microscopy of subcortical structures within an intact mouse brain,” Nat. Photonics 7(3), 205–209 (2013).
[Crossref] [PubMed]

D. Kobat, M. E. Durst, N. Nishimura, A. W. Wong, C. B. Schaffer, and C. Xu, “Deep tissue multiphoton microscopy using longer wavelength excitation,” Opt. Express 17(16), 13354–13364 (2009).
[Crossref] [PubMed]

Xu, Z. P.

Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
[Crossref]

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W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
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A. Li, H. Gong, B. Zhang, Q. Wang, C. Yan, J. Wu, Q. Liu, S. Zeng, and Q. Luo, “Micro-optical sectioning tomography to obtain a high-resolution atlas of the mouse brain,” Science 330(6009), 1404–1408 (2010).
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Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
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K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
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J. Luo, Z. Xie, J. W. Y. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, and B. Z. Tang, “Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole,” Chem. Commun. (Camb.) 18(18), 1740–1741 (2001).
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Q. Zheng, H. Zhu, S. C. Chen, C. Tang, E. Ma, and X. Chen, “Frequency-upconverted stimulated emission by simultaneous five-photon absorption,” Nat. Photonics 7(3), 234–239 (2013).
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H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
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Adv. Funct. Mater. (1)

W. Qin, D. Ding, J. Liu, W. Z. Yuan, Y. Hu, B. Liu, and B. Z. Tang, “Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications,” Adv. Funct. Mater. 22(4), 771–779 (2012).
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J. Qian, D. Wang, F. H. Cai, W. Xi, L. Peng, Z. F. Zhu, H. He, M. L. Hu, and S. He, “Observation of multiphoton-induced fluorescence from graphene oxide nanoparticles and applications in in vivo functional bioimaging,” Angew. Chem. Int. Ed. Engl. 51(42), 10570–10575 (2012).
[Crossref] [PubMed]

Biochem. Biophys. Res. Commun. (1)

T. S. Chen, S. Q. Zeng, Q. M. Luo, Z. H. Zhang, and W. Zhou, “High-order photobleaching of green fluorescent protein inside live cells in two-photon excitation microscopy,” Biochem. Biophys. Res. Commun. 291(5), 1272–1275 (2002).
[Crossref] [PubMed]

Biomaterials (1)

G. Feng, C. Y. Tay, Q. X. Chui, R. Liu, N. Tomczak, J. Liu, B. Z. Tang, D. T. Leong, and B. Liu, “Ultrabright organic dots with aggregation-induced emission characteristics for cell tracking,” Biomaterials 35(30), 8669–8677 (2014).
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G. S. He, L. S. Tan, Q. Zheng, and P. N. Prasad, “Multiphoton absorbing materials: Molecular designs, characterizations, and applications,” Chem. Rev. 108(4), 1245–1330 (2008).
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[Crossref] [PubMed]

J. Biomed. Opt. (1)

X. Yang and L. V. Wang, “Monkey brain cortex imaging by photoacoustic tomography,” J. Biomed. Opt. 13(4), 044009 (2008).
[Crossref] [PubMed]

J. Innov. Opt. Health Sci. (1)

Y. X. Wu, X. L. Liu, W. Zhou, X. H. Lv, and S. Q. Zeng, “Observing neuronal activities with random access two-photon microscope,” J. Innov. Opt. Health Sci. 2(01), 67–71 (2009).
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H. Cheng, W. Qin, Z. F. Zhu, J. Qian, A. J. Qin, B. Z. Tang, and S. L. He, “Nanoparticles with aggregation-induced emission for monitoring long time cell membrane interactions,” Prog. Electromagnetics Res. 140, 313–325 (2013).
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K. Li, W. Qin, D. Ding, N. Tomczak, J. Geng, R. Liu, J. Liu, X. Zhang, H. Liu, B. Liu, and B. Z. Tang, “Photostable fluorescent organic dots with aggregation-induced emission (AIE dots) for noninvasive long-term cell tracing,” Sci Rep 3, 1150 (2013).
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Z. F. Zhu, X. Y. Zhao, W. Qin, G. D. Chen, J. Qian, and Z. P. Xu, “Fluorescent AIE dots encapsulated organically modified silica (ORMOSIL) nanoparticles for two-photon cellular imaging,” Sci. China-Chem. 56(9), 1247–1252 (2013).
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Supplementary Material (2)

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Figures (9)

Fig. 1
Fig. 1 (a) Chemical structure of TPE-TPP molecule. (b) Photographs of DMSO solution (left), DMF solution (middle) and solid powder (right) of TPE-TPP taken under UV irradiation. Concentration of TPE-TPP: 10 μM.
Fig. 2
Fig. 2 (a) Absorption spectrum of TPE-TPP. (b) Fluorescence spectrum of TPE-TPP (5 μM) nanoaggregates in water, under the excitation of 320 nm. (c) A typical TEM image of TPE-TPP nanoaggregates. Scale bar: 500 nm.
Fig. 3
Fig. 3 Fluorescence intensity changes of TPE-TPP (5 μM) nanoaggregates treated with PBS, and pH 4 to 10 solutions for 18 h (normalized by the initial fluorescence peak intensity at 0 h). Excitation wavelength: 320 nm.
Fig. 4
Fig. 4 (a) Transmission spectrum of TPE-TPP in DMSO (1 cm-thickness). (b) Two-photon fluorescence spectrum of TPE-TPP in solid state. (c) Square dependence of two-photon fluorescence of solid TPE-TPP on excitation intensity of the 740 nm-fs laser.
Fig. 5
Fig. 5 Two-photon fluorescence images of primary neurons treated with TPE-TPP (5 μM) for 2 hours, under the excitation of a fs laser at 740 nm. (a) Fluorescence channel, (b) Bright-field channel, and (c) Merged channel. The scale bar is 50 μm.
Fig. 6
Fig. 6 (a) Two-photon fluorescence intensity (%) of TPE-TPP in neurons with increasing number of scans. Excitation time: 4.2 s/scan; excitation wavelength of the fs laser: 740 nm. (b) Loss ratio of two-photon fluorescence intensity [(two-photon fluorescence intensity before each scan - two-photon fluorescence intensity after each scan)/two-photon fluorescence intensity after each scan] with the two-photon fluorescence intensity (%) after each scan.
Fig. 7
Fig. 7 (a) A reconstructed 3D image illustrating the staining of TPE-TPP in the microglia of a mouse’s brain (30 minutes post-treatment) via the two-photon scanning microscope. Scale bar: 50 μm. (b) A magnified 3D two-photon fluorescence image of the brain of a mouse. Scale bar: 50 μm.
Fig. 8
Fig. 8 2D two-photon fluorescence images at different sections of the in vivo mouse brain. (a) The image at the top section. (b) The image at the middle section. (c) The image at the bottom section. Scale bar: 50 μm.
Fig. 9
Fig. 9 (a) 2D two-photon fluorescence images of a mouse’s brain treated with TPE-TPP, with increasing number of scans (1st, 27th, 54th, and 81st scan; excitation time: 4.2 s/scan). Scale bar: 50 μm (Media 1 and Media 2). (b) Two-photon fluorescence intensity (%) of TPE-TPP in the microglia with increasing scanning time. (c) Loss ratio of two-photon fluorescence intensity [(two-photon fluorescence intensity before each scan - two-photon fluorescence intensity after each scan)/two-photon fluorescence intensity after each scan] with the two-photon fluorescence intensity (%) after each scan.

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