Abstract

Insulin–gold nanoclusters exhibit outstanding biocompatibility, photostability, and fluorescence quantum efficiency. However, they have never been used in superresolution microscopy, which requires nonlinear switching or saturation of fluorescence. Here we examine the fluorescence and stimulated emission depletion properties of gold nanoclusters. Their bleaching rate is very slow, demonstrating superior photostability. Surprisingly, however, the best depletion efficiency is less than 70%, whereas the depletion intensity requirement is much higher than the expectation from a simple two-level model. Fluorescence lifetime measurement revealed two distinct lifetime components, which indicate intersystem and reverse intersystem crossing during excitation. Based on population dynamic calculation, excellent agreement of the maximal depletion efficiency is found. Our work not only features the first examination of STED with metallic clusters, but also reveals the significance of molecular transition dynamics when considering a STED labeling.

© 2015 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
    [Crossref] [PubMed]
  2. B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
    [Crossref] [PubMed]
  3. S. W. Hell, “Far-field optical nanoscopy,” Science 316(5828), 1153–1158 (2007).
    [Crossref] [PubMed]
  4. M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
    [Crossref] [PubMed]
  5. S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
    [Crossref] [PubMed]
  6. R. Heintzmann, T. M. Jovin, and C. Cremer, “Saturated patterned excitation microscopy--a concept for optical resolution improvement,” J. Opt. Soc. Am. A 19(8), 1599–1609 (2002).
    [Crossref] [PubMed]
  7. V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
    [Crossref] [PubMed]
  8. D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
    [Crossref] [PubMed]
  9. E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
    [Crossref]
  10. T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
    [Crossref] [PubMed]
  11. C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).
  12. X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
    [Crossref]
  13. C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
    [Crossref] [PubMed]
  14. B. Harke, J. Keller, C. K. Ullal, V. Westphal, A. Schönle, and S. W. Hell, “Resolution scaling in STED microscopy,” Opt. Express 16(6), 4154–4162 (2008).
    [Crossref] [PubMed]
  15. S. W. Hell, “Toward fluorescence nanoscopy,” Nat. Biotechnol. 21(11), 1347–1355 (2003).
    [Crossref] [PubMed]
  16. E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
    [Crossref] [PubMed]
  17. J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
    [Crossref] [PubMed]
  18. S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
    [Crossref]
  19. B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
    [Crossref] [PubMed]
  20. J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
    [Crossref] [PubMed]

2014 (1)

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

2013 (1)

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

2012 (1)

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

2011 (2)

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

2010 (2)

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

2009 (4)

B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
[Crossref] [PubMed]

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

2008 (3)

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

B. Harke, J. Keller, C. K. Ullal, V. Westphal, A. Schönle, and S. W. Hell, “Resolution scaling in STED microscopy,” Opt. Express 16(6), 4154–4162 (2008).
[Crossref] [PubMed]

2007 (2)

S. W. Hell, “Far-field optical nanoscopy,” Science 316(5828), 1153–1158 (2007).
[Crossref] [PubMed]

J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
[Crossref] [PubMed]

2006 (2)

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

2003 (1)

S. W. Hell, “Toward fluorescence nanoscopy,” Nat. Biotechnol. 21(11), 1347–1355 (2003).
[Crossref] [PubMed]

2002 (1)

Bates, M.

B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
[Crossref] [PubMed]

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

Bell, T. D.

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

Betzig, E.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Bock, H.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Bonifacino, J. S.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Bückers, J.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Chan, W. H.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Chandler, B.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Chang, H. W.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Chang, W. H.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Cheng, J. T.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Chien, Y. C.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Chou, P. T.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Chu, S. W.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Cremer, C.

Davidson, M. W.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

De Schryver, F. C.

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

Dedecker, P.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Dickson, R. M.

J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
[Crossref] [PubMed]

Eggeling, C.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

Fron, E.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Fujita, K.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Gilbertson, J. D.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Goodson, T.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Grotjohann, T.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Han, K. Y.

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

Harke, B.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

B. Harke, J. Keller, C. K. Ullal, V. Westphal, A. Schönle, and S. W. Hell, “Resolution scaling in STED microscopy,” Opt. Express 16(6), 4154–4162 (2008).
[Crossref] [PubMed]

Heintzmann, R.

Hell, S. W.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

B. Harke, J. Keller, C. K. Ullal, V. Westphal, A. Schönle, and S. W. Hell, “Resolution scaling in STED microscopy,” Opt. Express 16(6), 4154–4162 (2008).
[Crossref] [PubMed]

S. W. Hell, “Far-field optical nanoscopy,” Science 316(5828), 1153–1158 (2007).
[Crossref] [PubMed]

S. W. Hell, “Toward fluorescence nanoscopy,” Nat. Biotechnol. 21(11), 1347–1355 (2003).
[Crossref] [PubMed]

Hess, H. F.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Hofkens, J.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

Hotta, J.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Hsiao, J. K.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Hsiao, Y. H.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Hsieh, J. T.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Hsu, A. C.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Huang, B.

B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
[Crossref] [PubMed]

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

Huang, Y. T.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Irvine, S. E.

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

Jahn, R.

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

Jakobs, S.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Janssen, K. P. F.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Jovin, T. M.

Kamin, D.

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

Kastrup, L.

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

Kawano, S.

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Kawata, S.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Keller, J.

Lai, C. W.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Lauterbach, M. A.

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

Lavoie-Cardinal, F.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Lee, C. H.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Lee, H.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Lee, M. Y.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Lee, Y. C.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Leutenegger, M.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Li, C.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Li, J. K.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Lin, C. A. J.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Lindwasser, O. W.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Lippincott-Schwartz, J.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Liu, C. L.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Medda, R.

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

Melnikov, S. M.

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

Müllen, K.

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

Nicovich, P. R.

J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
[Crossref] [PubMed]

Oketani, R.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Olenych, S.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Patterson, G. H.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Peng, Y. K.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Ramakrishna, G.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Rittweger, E.

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

Rizzoli, S. O.

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

Schönle, A.

Shen, J. L.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Shih, C. W.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Smith, N. I.

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Sougrat, R.

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

Su, T. Y.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Tang, J.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Tang, K. C.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Testa, I.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Toh, Y. R.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Uegaki, K.

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Ullal, C. K.

Urban, N. T.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Varnavski, O.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Wang, H. H.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Wang, W.

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

Wen, X. M.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Westphal, V.

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

B. Harke, J. Keller, C. K. Ullal, V. Westphal, A. Schönle, and S. W. Hell, “Resolution scaling in STED microscopy,” Opt. Express 16(6), 4154–4162 (2008).
[Crossref] [PubMed]

Wildanger, D.

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

Willig, K. I.

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Wu, H. T.

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Wu, H. Y.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Yamanaka, M.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Yau, S. H.

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

Yeh, H. I.

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

Yeow, E. K.

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

Yonemaru, Y.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

Yu, P.

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Zheng, J.

J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
[Crossref] [PubMed]

Zhuang, X.

B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
[Crossref] [PubMed]

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

Zhuo, G. Y.

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Angew. Chem. Int. Ed. Engl. (1)

C. L. Liu, H. T. Wu, Y. H. Hsiao, C. W. Lai, C. W. Shih, Y. K. Peng, K. C. Tang, H. W. Chang, Y. C. Chien, J. K. Hsiao, J. T. Cheng, and P. T. Chou, “Insulin-directed synthesis of fluorescent gold nanoclusters: preservation of insulin bioactivity and versatility in cell imaging,” Angew. Chem. Int. Ed. Engl. 50(31), 7056–7060 (2011).
[Crossref] [PubMed]

Annu. Rev. Biochem. (1)

B. Huang, M. Bates, and X. Zhuang, “Super-resolution fluorescence microscopy,” Annu. Rev. Biochem. 78(1), 993–1016 (2009).
[Crossref] [PubMed]

Annu. Rev. Phys. Chem. (1)

J. Zheng, P. R. Nicovich, and R. M. Dickson, “Highly fluorescent noble-metal quantum dots,” Annu. Rev. Phys. Chem. 58(1), 409–431 (2007).
[Crossref] [PubMed]

J. Am. Chem. Soc. (1)

J. Hotta, E. Fron, P. Dedecker, K. P. F. Janssen, C. Li, K. Müllen, B. Harke, J. Bückers, S. W. Hell, and J. Hofkens, “Spectroscopic rationale for efficient stimulated-emission depletion microscopy fluorophores,” J. Am. Chem. Soc. 132(14), 5021–5023 (2010).
[Crossref] [PubMed]

J. Biomed. Opt. (1)

M. Yamanaka, Y. Yonemaru, S. Kawano, K. Uegaki, N. I. Smith, S. Kawata, and K. Fujita, “Saturated excitation microscopy for sub-diffraction-limited imaging of cell clusters,” J. Biomed. Opt. 18(12), 126002 (2013).
[Crossref] [PubMed]

J. Med. Biol. Eng. (1)

C. A. J. Lin, C. H. Lee, J. T. Hsieh, H. H. Wang, J. K. Li, J. L. Shen, W. H. Chan, H. I. Yeh, and W. H. Chang, “Synthesis of fluorescent metallic nanoclusters toward biomedical application: recent progress and present challenges,” J. Med. Biol. Eng. 29, 276–283 (2009).

J. Microsc. (1)

D. Wildanger, R. Medda, L. Kastrup, and S. W. Hell, “A compact STED microscope providing 3D nanoscale resolution,” J. Microsc. 236(1), 35–43 (2009).
[Crossref] [PubMed]

J. Opt. Soc. Am. A (1)

J. Phys. Chem. A (1)

E. K. Yeow, S. M. Melnikov, T. D. Bell, F. C. De Schryver, and J. Hofkens, “Characterizing the fluorescence intermittency and photobleaching kinetics of dye molecules immobilized on a glass surface,” J. Phys. Chem. A 110(5), 1726–1734 (2006).
[Crossref] [PubMed]

J. Phys. Chem. C (2)

S. H. Yau, O. Varnavski, J. D. Gilbertson, B. Chandler, G. Ramakrishna, and T. Goodson, “Ultrafast optical study of small gold monolayer protected clusters: a closer look at emission,” J. Phys. Chem. C 114(38), 15979–15985 (2010).
[Crossref]

X. M. Wen, P. Yu, Y. R. Toh, A. C. Hsu, Y. C. Lee, and J. Tang, “Fluorescence dynamics in BSA-protected Au-25 nanoclusters,” J. Phys. Chem. C 116(35), 19032–19038 (2012).
[Crossref]

Nat. Biotechnol. (1)

S. W. Hell, “Toward fluorescence nanoscopy,” Nat. Biotechnol. 21(11), 1347–1355 (2003).
[Crossref] [PubMed]

Nat. Photonics (1)

E. Rittweger, K. Y. Han, S. E. Irvine, C. Eggeling, and S. W. Hell, “STED microscopy reveals crystal colour centres with nanometric resolution,” Nat. Photonics 3(3), 144–147 (2009).
[Crossref]

Nature (1)

T. Grotjohann, I. Testa, M. Leutenegger, H. Bock, N. T. Urban, F. Lavoie-Cardinal, K. I. Willig, C. Eggeling, S. Jakobs, and S. W. Hell, “Diffraction-unlimited all-optical imaging and writing with a photochromic GFP,” Nature 478(7368), 204–208 (2011).
[Crossref] [PubMed]

Opt. Express (1)

Phys. Rev. Lett. (1)

S. W. Chu, T. Y. Su, R. Oketani, Y. T. Huang, H. Y. Wu, Y. Yonemaru, M. Yamanaka, H. Lee, G. Y. Zhuo, M. Y. Lee, S. Kawata, and K. Fujita, “Measurement of a saturated emission of optical radiation from gold nanoparticles: application to an ultrahigh resolution microscope,” Phys. Rev. Lett. 112(1), 017402 (2014).
[Crossref] [PubMed]

Science (4)

E. Betzig, G. H. Patterson, R. Sougrat, O. W. Lindwasser, S. Olenych, J. S. Bonifacino, M. W. Davidson, J. Lippincott-Schwartz, and H. F. Hess, “Imaging intracellular fluorescent proteins at nanometer resolution,” Science 313(5793), 1642–1645 (2006).
[Crossref] [PubMed]

B. Huang, W. Wang, M. Bates, and X. Zhuang, “Three-dimensional super-resolution imaging by stochastic optical reconstruction microscopy,” Science 319(5864), 810–813 (2008).
[Crossref] [PubMed]

S. W. Hell, “Far-field optical nanoscopy,” Science 316(5828), 1153–1158 (2007).
[Crossref] [PubMed]

V. Westphal, S. O. Rizzoli, M. A. Lauterbach, D. Kamin, R. Jahn, and S. W. Hell, “Video-rate far-field optical nanoscopy dissects synaptic vesicle movement,” Science 320(5873), 246–249 (2008).
[Crossref] [PubMed]

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (3)

Fig. 1
Fig. 1

(a) Schematics of the experimental setup. The excitation and depletion beams are combined and sent into a laser scanning confocal microscope. The epi-collected fluorescence is guided through a dichroic mirror (DM), confocal aperture (CA), and suitable filters before reaching the photomultiplier tube (PMT). Insets show the emission spectrum and TEM image of IGNCs (scale bar: 5 nm). (b) Axial overlap and (c) temporal separation of the excitation (black) and depletion (red) beams.

Fig. 2
Fig. 2

(a) Fluorescence depletion curve of an IGNC film. Black rectangles are experimental results, and the corresponding exponential fitting is given as an equation and a red curve. Inset shows initial fluorescence image (exc. only) and image after depletion (exc. + dep.). Scale bar: 2 μm. Blue dashed line marks the position of 50% depletion and the corresponding value of Is. (b) Bleaching of IGNC fluorescence and its reversible depletion. Red triangles and curve show photobleaching with only an excitation beam on IGNC film; green curve shows photobleaching when the depletion beam is added. The fluorescence can be repetitively switched on and off, as shown by the black rectangles.

Fig. 3
Fig. 3

(a) Fluorescence lifetime measurement of IGNC film. Green line is the fitting with two exponential components, whose corresponding lifetimes and coefficients are given in the inset equation. (b) Schematic of energy levels of IGNCs. The ISC and RISC processes are shown. PF: prompt fluorescence; DF: delayed fluorescence.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

d [ S ] t dt = k f [ S ] t k isc [ S ] t + k risc [ T ] t ; d [ T ] t dt = k isc [ S ] t k risc [ T ] t k p [ T ] t ,
[ S ] t = [ S ] 0 { k risc k isc + k risc e ( k f + k p k isc k risc 1+ k isc k risc )t + k isc k isc + k risc e ( k isc + k risc )t }; [ T ] t = [ S ] 0 { k isc k isc + k risc e ( k f + k p k isc k risc 1+ k isc k risc )t k isc k isc + k risc e ( k isc + k risc )t } .

Metrics