Skip to main content
Log in

Luminescent metal nanoclusters for biomedical applications

  • Review Article
  • Published:
Nano Research Aims and scope Submit manuscript

Abstract

Luminescent metal nanoclusters (NCs) have recently emerged as a novel class of luminescent nanomaterials and hold significant potential in biomedicine owing to their ultrasmall (< 2 nm) size, excellent photostability, and good biocompatibility. The recent rapid advances in the synthesis and functionalization of luminescent metal NCs have enabled scientists to develop colorful nanomaterials and nanodevices for a wide range of biomedical applications. In this review, we summarize the characteristics and advantages of luminescence from metal NCs, and highlight their applications in biomedicine. We focus on the research in biomedical detection, bio-imaging, drug delivery, and therapy, especially for the advances in the last five years. Luminescent metal NCs display a series of unique superiorities in biomedical applications, and the recent achievements have brought a lot of benefits to the diagnosis and treatment of clinical diseases, especially for tumors and cancers. Finally, we put forward the main challenges that currently still hinder the basic science studies and the practical development of luminescent metal NCs in biomedical applications. Overall, we expect that luminescent metal NCs will play a much more important role in future biomedicine and clinical applications.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Kreibig, U.; Vollmer, M. Optical Properties of Metal Clusters; Springer: Berlin, Heidelberg, 1995.

    Google Scholar 

  2. Ashcroft, N. W.; Mermin, N. D. Solid State Physics; Holt, Rinehart and Winston: New York, 1976.

    Google Scholar 

  3. Zheng, J.; Nicovich, P. R.; Dickson, R. M. Highly fluorescent noble-metal quantum dots. Annu. Rev. Phys. Chem. 2007, 58, 409–431.

    Google Scholar 

  4. Jin, R. C. Atomically precise metal nanoclusters: Stable sizes and optical properties. Nanoscale 2015, 7, 1549–1565.

    Google Scholar 

  5. Aikens, C. M. Electronic structure of ligand-passivated gold and silver nanoclusters. J. Phys. Chem. Lett. 2011, 2, 99–104.

    Google Scholar 

  6. Desireddy, A.; Conn, B. E.; Guo, J. S,; Yoon, B.; Barnett, R. N.; Monahan, B. M.; Kirschbaum, K.; Griffith, W. P.; Whetten, R. L.; Landman, U. et al. Ultrastable silver nanoparticles. Nature 2013, 501, 399–402.

    Google Scholar 

  7. Jin, R. C.; Zeng, C. J.; Zhou, M.; Chen, Y. X. Atomically precise colloidal metal nanoclusters and nanoparticles: Fundamentals and opportunities. Chem. Rev. 2016, 116, 10346–10413.

    Google Scholar 

  8. Jin, R. C. Quantum sized, thiolate-protected gold nanoclusters. Nanoscale 2010, 2, 343–362.

    Google Scholar 

  9. Shang, L.; Dong, S. J.; Nienhaus, G. U. Ultra-small fluorescent metal nanoclusters: Synthesis and biological applications. Nano Today 2011, 6, 401–418.

    Google Scholar 

  10. Lu, Y. Z.; Wei, W. T.; Chen, W. Copper nanoclusters: Synthesis, characterization and properties. Chin. Sci. Bull. 2012, 57, 41–47.

    Google Scholar 

  11. Xu, H. X.; Suslick, K. S. Water-soluble fluorescent silver nanoclusters. Adv. Mater. 2010, 22, 1078–1082.

    Google Scholar 

  12. Aiken III, J. D.; Finke, R. G. A review of modern transition-metal nanoclusters: Their synthesis, characterization, and applications in catalysis. J. Mol. Catal. A Chem. 1999, 145, 1–44.

    Google Scholar 

  13. Wilcoxon, J. P.; Abrams, B. L. Synthesis, structure and properties of metal nanoclusters. Chem. Soc. Rev. 2006, 35, 1162–1194.

    Google Scholar 

  14. Díez, I.; Ras, R. H. A. Fluorescent silver nanoclusters. Nanoscale 2011, 3, 1963–1970.

    Google Scholar 

  15. Jia, J. H.; Wang, Q. M. Intensely luminescent gold(I)−silver(I) cluster with hypercoordinated carbon. J. Am. Chem. Soc. 2009, 131, 16634–16635.

    Google Scholar 

  16. Jia, J. H.; Liang, J. X.; Lei, Z.; Cao, Z. X.; Wang, Q. M. A luminescent gold(I)–copper(I) cluster with unprecedented carbon-centered trigonal prismatic hexagold. Chem. Commun. 2011, 47, 4739–4741.

    Google Scholar 

  17. Lei, Z.; Pei, X. L.; Guan, Z. J.; Wang, Q. M. Full protection of intensely luminescent gold(I)–silver(I) cluster by phosphine ligands and inorganic anions. Angew. Chem., Int. Ed. 2017, 56, 7117–7120.

    Google Scholar 

  18. Bootharaju, M. S.; Joshi, C. P.; Parida, M. R.; Mohammed, O. F.; Bakr, O. M. Templated atom-precise galvanic synthesis and structure elucidation of a[Ag24Au(SR)18]− nanocluster. Angew. Chem., Int. Ed. 2016, 128, 934–938.

    Google Scholar 

  19. Kang, X.; Xiong, L.; Wang, S. X.; Yu, H. Z.; Jin, S.; Song, Y. B.; Chen, T.; Zheng, L. W.; Pan, C. S.; Pei, Y. et al. Shape-controlled synthesis of trimetallic nanoclusters: Structure elucidation and properties investigation. Chem.—Eur. J. 2016, 22, 17145–17150.

    Google Scholar 

  20. Bain, C. D.; Troughton, E. B.; Tao, Y. T.; Evall, J.; Whitesides, G. M.; Nuzzo, R. G. Formation of monolayer films by the spontaneous assembly of organic thiols from solution onto gold. J. Am. Chem. Soc. 1989, 111, 321–335.

    Google Scholar 

  21. Song, X. R.; Goswami, N.; Yang, H. H.; Xie, J. P. Functionalization of metal nanoclusters for biomedical applications. Analyst 2016, 141, 3126–3140.

    Google Scholar 

  22. Petty, J. T.; Fan, C. Y.; Story, S. P.; Sengupta, B.; St. John Iyer, A.; Prudowsky, Z.; Dickson, R. M. DNA encapsulation of 10 silver atoms producing a bright, modulatable, near-infrared-emitting cluster. J. Phys. Chem. Lett. 2010, 1, 2524–2529.

    Google Scholar 

  23. Xie, J. P.; Zheng, Y. G.; Ying, J. Y. Protein-directed synthesis of highly fluorescent gold nanoclusters. J. Am. Chem. Soc. 2009, 131, 888–889.

    Google Scholar 

  24. Zhang, Q.; Yang, M. Y.; Zhu, Y.; Mao, C. B. Metallic nanoclusters for cancer imaging and therapy. Curr. Med. Chem. 2018, 25, 1379–1396.

    Google Scholar 

  25. Zhu, M. Z.; Lanni, E.; Garg, N.; Bier, M. E.; Jin, R. C. Kinetically controlled, high-yield synthesis of Au25 clusters. J. Am. Chem. Soc. 2008, 130, 1138–1139.

    Google Scholar 

  26. Kumar, S.; Jin, R. C. Water-soluble Au25(capt)18 nanoclusters: Synthesis, thermal stability, and optical properties. Nanoscale 2012, 4, 4222–4227.

    Google Scholar 

  27. Tvedte, L. M.; Ackerson, C. J. Size-focusing synthesis of gold nanoclusters with p-mercaptobenzoic acid. J. Phys. Chem. A 2014, 118, 8124–8128.

    Google Scholar 

  28. Wu, Z. K.; Suhan, J.; Jin, R. C. One-pot synthesis of atomically monodisperse, thiol-functionalized Au25 nanoclusters. J. Mater. Chem. 2009, 19, 622–626.

    Google Scholar 

  29. Wu, Z. K.; MacDonald, M. A.; Chen, J.; Zhang, P.; Jin, R. C. Kinetic control and thermodynamic selection in the synthesis of atomically precise gold nanoclusters. J. Am. Chem. Soc. 2011, 133, 9670–9673.

    Google Scholar 

  30. Qian, H. F.; Eckenhoff, W. T.; Zhu, Y.; Pintauer, T.; Jin, R. C. Total structure determination of thiolate-protected Au38 nanoparticles. J. Am. Chem. Soc. 2010, 132, 8280–8281.

    Google Scholar 

  31. Qian, H. F.; Zhu, Y.; Jin, R. C. Size-focusing synthesis, optical and electrochemical properties of monodisperse Au38(SC2H4Ph)24 nanoclusters. ACS Nano 2009, 3, 3795–3803.

    Google Scholar 

  32. Zeng, C. J.; Chen, Y. X.; Li, G.; Jin, R. C. Magic size Au64(S-c-C6H11)32 nanocluster protected by cyclohexanethiolate. Chem. Mater. 2014, 26, 2635–2641.

    Google Scholar 

  33. Liu, C.; Lin, J. Z.; Shi, Y. W.; Li, G. Efficient synthesis of Au99(SR)42 nanoclusters. Nanoscale 2015, 7, 5987–5990.

    Google Scholar 

  34. Qian, H. F.; Jin, R. C. Controlling nanoparticles with atomic precision: The case of Au144(SCH2CH2Ph)60. Nano Lett. 2009, 9, 4083–4087.

    Google Scholar 

  35. Zeng, C. J.; Chen, Y. X.; Kirschbaum, K.; Lambright, K. J.; Jin, R. C. Emergence of hierarchical structural complexities in nanoparticles and their assembly. Science 2016, 354, 1580–1584.

    Google Scholar 

  36. Qian, H. F.; Zhu, Y.; Jin, R. C. Atomically precise gold nanocrystal molecules with surface Plasmon resonance. Proc. Natl. Acad. Sci. USA 2012, 109, 696–700.

    Google Scholar 

  37. Joshi, C. P.; Bootharaju, M. S.; Alhilaly, M. J.; Bakr, O. M. [Ag25(SR)18]−: The “golden” silver nanoparticle. J. Am. Chem. Soc. 2015, 137, 11578–11581.

    Google Scholar 

  38. Nguyen, T. A. D.; Jones, Z. R.; Leto, D. F.; Wu, G.; Scott, S. L.; Hayton, T. W. Ligand-exchange-induced growth of an atomically precise Cu29 nanocluster from a smaller cluster. Chem. Mater. 2016, 28, 8385–8390.

    Google Scholar 

  39. Wan, X. K.; Cheng, X. L.; Tang, Q.; Han, Y. Z.; Hu, G. X.; Jiang, D. E.; Wang, Q. M. Atomically precise bimetallic Au19Cu30 nanocluster with an icosidodecahedral Cu30 shell and an alkynyl–Cu interface. J. Am. Chem. Soc. 2017, 139, 9451–9454.

    Google Scholar 

  40. Kang, X.; Wang, S. X.; Song, Y. B.; Jin, S.; Sun, G. D.; Yu, H. Z.; Zhu, M. Z. Bimetallic Au2Cu6 nanoclusters: Strong luminescence induced by the aggregation of copper(I) complexes with gold(0) species. Angew. Chem., Int. Ed. 2016, 55, 3611–3614.

    Google Scholar 

  41. Kumar, S.; Bolan, M. D.; Bigioni, T. P. Glutathione-stabilized magic-number silver cluster compounds. J. Am. Chem. Soc. 2010, 132, 13141–13143.

    Google Scholar 

  42. Alvarez, M. M.; Khoury, J. T.; Schaaff, T. G.; Shafigullin, M. N.; Vezmar, I.; Whetten, R. L. Optical absorption spectra of nanocrystal gold molecules. J. Phys. Chem. B. 1997, 101, 3706–3712.

    Google Scholar 

  43. Zhou, M.; Zeng, C. J.; Song, Y. B.; Padelford, J. W.; Wang, G. L.; Sfeir, M. Y.; Higaki, T.; Jin, R. C. On the non-metallicity of 2.2 nm Au246(SR)80 nanoclusters. Angew. Chem., Int. Ed. 2017, 56, 16257–16261.

    Google Scholar 

  44. Higaki, T.; Zhou, M.; Lambright, K. J.; Kirschbaum, K.; Sfeir, M. Y.; Jin, R. C. Sharp transition from nonmetallic Au246 to metallic Au279 with nascent surface Plasmon resonance. J. Am. Chem. Soc. 2018, 140, 5691–5695.

    Google Scholar 

  45. Liu, J. H.; Wang, A. Q.; Chi, Y. S.; Lin, H. P.; Mou, C. Y. Synergistic effect in an Au−Ag alloy nanocatalyst: CO oxidation. J. Phys. Chem. B 2005, 109, 40–43.

    Google Scholar 

  46. Yamazoe, S.; Koyasu, K.; Tsukuda, T. Nonscalable oxidation catalysis of gold clusters. Acc. Chem. Res. 2014, 47, 816–824.

    Google Scholar 

  47. Zheng, K. Y.; Setyawati, M. I.; Leong, D. T.; Xie, J. P. Antimicrobial gold nanoclusters. ACS Nano 2017, 11, 6904–6910.

    Google Scholar 

  48. Zheng, J.; Zhou, C.; Yu, M. X.; Liu, J. B. Different sized luminescent gold nanoparticles. Nanoscale 2012, 4, 4073–4083.

    Google Scholar 

  49. Huang, T.; Murray, R. W. Visible luminescence of water-soluble monolayerprotected gold clusters. J. Phys. Chem. B 2001, 105, 12498–12502.

    Google Scholar 

  50. Huang, T.; Murray, R. W. Luminescence of tiopronin monolayer-protected silver clusters changes to that of gold clusters upon galvanic core metal exchange. J. Phys. Chem. B 2003, 107, 7434–7440.

    Google Scholar 

  51. Zhu, M. Z.; Aikens, C. M.; Hollander, F. J.; Schatz, G. C.; Jin, R. C. Correlating the crystal structure of a thiol-protected Au25 cluster and optical properties. J. Am. Chem. Soc. 2008, 130, 5883–5885.

    Google Scholar 

  52. Lu, Y. Z.; Chen, W. Sub-nanometre sized metal clusters: From synthetic challenges to the unique property discoveries. Chem. Soc. Rev. 2012, 41, 3594–3623.

    Google Scholar 

  53. Zheng, J.; Petty, J. T.; Dickson, R. M. High quantum yield blue emission from water-soluble Au8 nanodots. J. Am. Chem. Soc. 2003, 125, 7780–7781.

    Google Scholar 

  54. Zheng, J.; Zhang, C. W.; Dickson, R. M. Highly fluorescent, water-soluble, size-tunable gold quantum dots. Phys. Rev. Lett. 2004, 93, 077402.

    Google Scholar 

  55. Liu, X. F.; Li, C. H.; Xu, J. L.; Lv, J.; Zhu, M.; Guo, Y. B.; Cui, S.; Liu, H. B.; Wang, S.; Li, Y. L. Surfactant-free synthesis and functionalization of highly fluorescent gold quantum dots. J. Phys. Chem. C 2008, 112, 10778–10783.

    Google Scholar 

  56. Yang, X.; Shi, M. M.; Zhou, R. J.; Chen, X. Q.; Chen, H. Z. Blending of HAuCl4 and histidine in aqueous solution: A simple approach to the Au10 cluster. Nanoscale 2011, 3, 2596–2601.

    Google Scholar 

  57. Sun, C. J.; Yang, H.; Yuan, Y.; Tian, X.; Wang, L. M.; Guo, Y.; Xu, L.; Lei, J. L.; Gao, N.; Anderson, G. J. et al. Controlling assembly of paired gold clusters within apoferritin nanoreactor for in vivo kidney targeting and biomedical imaging. J. Am. Chem. Soc. 2011, 133, 8617–8624.

    Google Scholar 

  58. Huang, X.; Li, B. Y.; Li, L.; Zhang, H.; Majeed, I.; Hussain, I.; Tan, B. Facile preparation of highly blue fluorescent metal nanoclusters in organic media. J. Phys. Chem. C 2012, 116, 448–455.

    Google Scholar 

  59. Shang, L.; Dörlich, R. M.; Brandholt, S.; Schneider, R.; Trouillet, V.; Bruns, M.; Gerthsen, D.; Nienhaus, G. U. Facile preparation of water-soluble fluorescent gold nanoclusters for cellular imaging applications. Nanoscale 2011, 3, 2009–2014.

    Google Scholar 

  60. Wang, H. H.; Lin, C. A. J.; Lee, C. H.; Lin, Y. C.; Tseng, Y. M.; Hsieh, C. L.; Chen, C. H.; Tsai, C. H.; Hsieh, C. T.; Shen, J. L. et al. Fluorescent gold nanoclusters as a biocompatible marker for in vitro and in vivo tracking of endothelial cells. ACS Nano 2011, 5, 4337–4344.

    Google Scholar 

  61. Zhou, C.; Long, M.; Qin, Y. P.; Sun, X. K.; Zheng, J. Luminescent gold nanoparticles with efficient renal clearance. Angew. Chem., Int. Ed. 2011, 50, 3168–3172.

    Google Scholar 

  62. Kawasaki, H.; Hamaguchi, K.; Osaka, I.; Arakawa, R. Ph-dependent synthesis of pepsin-mediated gold nanoclusters with blue green and red fluorescent emission. Adv. Funct. Mater. 2011, 21, 3508–3515.

    Google Scholar 

  63. Shang, L.; Yang, L. X.; Stockmar, F.; Popescu, R.; Trouillet, V.; Bruns, M.; Gerthsen, D.; Nienhaus, G. U. Microwave-assisted rapid synthesis of luminescent gold nanoclusters for sensing Hg2+ in living cells using fluorescence imaging. Nanoscale 2012, 4, 4155–4160.

    Google Scholar 

  64. Yuan, X.; Luo, Z. T.; Zhang, Q. B.; Zhang, X. H.; Zheng, Y. G.; Lee, J. Y.; Xie, J. P. Synthesis of highly fluorescent metal (Ag, Au, Pt, and Cu) nanoclusters by electrostatically induced reversible phase transfer. ACS Nano 2011, 5, 8800–8808.

    Google Scholar 

  65. Wang, Z. J.; Wu, L. N.; Cai, W.; Jiang, Z. H. Luminescent Au11 nanocluster superlattices with high thermal stability. J. Mater. Chem. 2012, 22, 3632–3636.

    Google Scholar 

  66. Wang, Z. J.; Cai, W.; Sui, J. H. Blue luminescence emitted from monodisperse thiolate-capped Au11 clusters. Chem. Phys. Chem. 2009, 10, 2012–2015.

    Google Scholar 

  67. Bakr, O. M.; Amendola, V.; Aikens, C. M.; Wenseleers, W.; Li, R.; Dal Negro, L.; Schatz, G. C.; Stellacci, F. Silver nanoparticles with broad multiband linear optical absorption. Angew. Chem., Int. Ed. 2009, 48, 5921–5926.

    Google Scholar 

  68. Kim, Y.; Seff, K. Structure of a very small piece of silver metal. The octahedral silver (Ag6) molecule. Two crystal structures of partially decomposed vacuum-dehydrated fully Ag+-exchanged zeolite A. J. Am. Chem. Soc. 1977, 99, 7055–7057.

    Google Scholar 

  69. Zheng, J.; Dickson, R. M. Individual water-soluble dendrimer-encapsulated silver nanodot fluorescence. J. Am. Chem. Soc. 2002, 124, 13982–13983.

    Google Scholar 

  70. Shang, L.; Dong, S. J. Facile preparation of water-soluble fluorescent silver nanoclusters using a polyelectrolyte template. Chem. Commun. 2008, 1088–1090.

    Google Scholar 

  71. Choi, S.; Dickson, R. M.; Yu, J. H. Developing luminescent silver nanodots for biological applications. Chem. Soc. Rev. 2012, 41, 1867–1891.

    Google Scholar 

  72. O’Neill, P. R.; Young, K.; Schiffels, D.; Fygenson, D. K. Few-atom fluorescent silver clusters assemble at programmed sites on DNA nanotubes. Nano Lett. 2012, 12, 5464–5469.

    Google Scholar 

  73. Muhammed, M. A. H.; Aldeek, F.; Palui, G.; Trapiella-Alfonso, L.; Mattoussi, H. Growth of in situ functionalized luminescent silver nanoclusters by direct reduction and size focusing. ACS Nano 2012, 6, 8950–8961.

    Google Scholar 

  74. Zhang, H.; Huang, X.; Li, L.; Zhang, G. W.; Hussain, I.; Li, Z.; Tan, B. Photoreductive synthesis of water-soluble fluorescent metal nanoclusters. Chem. Commun. 2012, 48, 567–569.

    Google Scholar 

  75. Yang, X.; Gan, L. F.; Han, L.; Wang, E. K.; Wang, J. High-yield synthesis of silver nanoclusters protected by DNA monomers and DFT prediction of their photoluminescence properties. Angew. Chem., Int. Ed. 2013, 52, 2022–2026.

    Google Scholar 

  76. Kawasaki, H.; Kosaka, Y.; Myoujin, Y.; Narushima, T.; Yonezawa, T.; Arakawa, R. Microwave-assisted polyol synthesis of copper nanocrystals without using additional protective agents. Chem. Commun. 2011, 47, 7740–7742.

    Google Scholar 

  77. Chen, J.H.; Liu, J.; Fang, Z. Y.; Zeng, L. W. Random dsDNA-templated formation of copper nanoparticles as novel fluorescence probes for label-free lead ions detection. Chem. Commun. 2012, 48, 1057–1059.

    Google Scholar 

  78. Kawasaki, H.; Yamamoto, H.; Fujimori, H.; Arakawa, R.; Inada, M.; Iwasaki, Y. Surfactant-free solution synthesis of fluorescent platinum subnanoclusters. Chem. Commun. 2010, 46, 3759–3761.

    Google Scholar 

  79. Tanaka, S. I.; Miyazaki, J.; Tiwari, D. K.; Jin, T.; Inouye, Y. Fluorescent platinum nanoclusters: Synthesis, purification, characterization, and application to bioimaging. Angew. Chem., Int. Ed. 2011, 50, 431–435.

    Google Scholar 

  80. Sun, H. T.; Matsushita, Y.; Sakka, Y.; Shirahata, N.; Tanaka, M.; Katsuya, Y.; Gao, H.; Kobayashi, K. Synchrotron X-ray, photoluminescence, and quantum chemistry studies of bismuth-embedded dehydrated zeolite Y. J. Am. Chem. Soc. 2012, 134, 2918–2921.

    Google Scholar 

  81. Sun, H. T.; Sakka, Y.; Gao, H.; Miwa, Y.; Fujii, M.; Shirahata, N.; Bai, Z. H.; Li, J. G. Ultrabroad near-infrared photoluminescence from Bi5(AlCl4)3 crystal. J. Mater. Chem. 2011, 21, 4060–4063.

    Google Scholar 

  82. Sun, H. T.; Sakka, Y.; Fujii, M.; Shirahata, N.; Gao, H. Ultrabroad nearinfrared photoluminescence from ionic liquids containing subvalent bismuth. Opt. Lett. 2011, 36, 100–102.

    Google Scholar 

  83. Sun, H. T.; Sakka, Y.; Shirahata, N.; Gao, H.; Yonezawa, T. Experimental and theoretical studies of photoluminescence from Bi8 2+ and Bi5 3+ stabilized by [AlCl4]− in molecular crystals. J. Mater. Chem. 2012, 22, 12837–12841.

    Google Scholar 

  84. Sun, H. T.; Xu, B. B.; Yonezawa, T.; Sakka, Y.; Shirahata, N.; Fujii, M.; Qiu, J. R.; Gao, H. Photoluminescence from Bi5(GaCl4)3 molecular crystal. Dalton Trans. 2012, 41, 11055–11061.

    Google Scholar 

  85. Sun, H. T.; Yonezawa, T.; Gillett-Kunnath, M. M.; Sakka, Y.; Shirahata, N.; Rong Gui, S. C.; Fujii, M.; Sevov, S. C. Ultra-broad near-infrared photoluminescence from crystalline (K-crypt)2Bi2 containing [Bi2]2− dimers. J. Mater. Chem. 2012, 22, 20175–20178.

    Google Scholar 

  86. Grasset, F.; Molard, Y.; Cordier, S.; Dorson, F.; Mortier, M.; Perrin, C.; Guilloux-Viry, M.; Sasaki, T.; Haneda, H. When “metal atom clusters” meet zno nanocrystals: A ((n-C4H9)4N)2Mo6Br14@ZnO hybrid. Adv. Mater. 2008, 20, 1710–1715.

    Google Scholar 

  87. Aubert, T.; Nerambourg, N.; Saito, N.; Haneda, H.; Ohashi, N.; Mortier, M.; Cordier, S.; Grasset, F. Tunable visible emission of luminescent hybrid nanoparticles incorporating two complementary luminophores: ZnO nanocrystals and [Mo6Br14]2− nanosized cluster units. Part. Part. Syst. Char. 2013, 30, 90–95.

    Google Scholar 

  88. Molard, Y.; Labbé, C.; Cardin, J.; Cordier, S. Sensitization of Er3+ infrared photoluminescence embedded in a hybrid organic-inorganic copolymer containing octahedral molybdenum clusters. Adv. Funct. Mater. 2013, 23, 4821–4825.

    Google Scholar 

  89. Udayabhaskararao, T.; Sun, Y.; Goswami, N.; Pal, S. K.; Balasubramanian, K.; Pradeep, T. Ag7Au6: A 13-atom alloy quantum cluster. Angew. Chem., Int. Ed. 2012, 51, 2155–2159.

    Google Scholar 

  90. Mohanty, J. S.; Xavier, P. L.; Chaudhari, K.; Bootharaju, M. S.; Goswami, N.; Pal, S. K.; Pradeep, T. Luminescent, bimetallic auag alloy quantum clusters in protein templates. Nanoscale 2012, 4, 4255–4262.

    Google Scholar 

  91. Andolina, C. M.; Dewar, A. C.; Smith, A. M.; Marbella, L. E.; Hartmann, M. J.; Millstone, J. E. Photoluminescent gold–copper nanoparticle alloys with composition-tunable near-infrared emission. J. Am. Chem. Soc. 2013, 135, 5266–5269.

    Google Scholar 

  92. Xu, H. X.; Suslick, K. S. Sonochemical synthesis of highly fluorescent Ag nanoclusters. ACS Nano 2010, 4, 3209–3214.

    Google Scholar 

  93. Wu, Z. K.; Jin, R. C. On the ligand’s role in the fluorescence of gold nanoclusters. Nano Lett. 2010, 10, 2568–2573.

    Google Scholar 

  94. Chang, H. Y.; Chang, H. T.; Hung, Y. L.; Hsiung, T. M.; Lin, Y. W.; Huang, C. C. Ligand effect on the luminescence of gold nanodots and its application for detection of total mercury ions in biological samples. RSC Adv. 2013, 3, 4588–4597.

    Google Scholar 

  95. Li, G.; Lei, Z.; Wang, Q. M. Luminescent molecular Ag−S nanocluster [Ag62S13(SBut)32](BF4)4. J. Am. Chem. Soc. 2010, 132, 17678–17679.

    Google Scholar 

  96. Jin, S.; Wang, S. X.; Song, Y. B.; Zhou, M.; Zhong, J.; Zhang, J.; Xia, A. D.; Pei, Y.; Chen, M.; Li, P. et al. Crystal structure and optical properties of the [Ag62S12(SBut)32]2+ nanocluster with a complete face-centered cubic kernel. J. Am. Chem. Soc. 2014, 136, 15559–15565.

    Google Scholar 

  97. Duan, H. W.; Nie, S. M. Etching colloidal gold nanocrystals with hyperbranched and multivalent polymers: A new route to fluorescent and water-soluble atomic clusters. J. Am. Chem. Soc. 2007, 129, 2412–2413.

    Google Scholar 

  98. Jin, R. C.; Nobusada, K. Doping and alloying in atomically precise gold nanoparticles. Nano Res. 2014, 7, 285–300.

    Google Scholar 

  99. Yao, C. H.; Lin, Y. J.; Yuan, J. Y.; Liao, L. W.; Zhu, M.; Weng, L. H.; Yang, J. L.; Wu, Z. K. Mono-cadmium vs mono-mercury doping of Au25 nanoclusters. J. Am. Chem. Soc. 2015, 137, 15350–15353.

    Google Scholar 

  100. Giepmans, B. N. G.; Adams, S. R.; Ellisman, M. H.; Tsien, R. Y. The fluorescent toolbox for assessing protein location and function. Science 2006, 312, 217–224.

    Google Scholar 

  101. Resch-Genger, U.; Grabolle, M.; Cavaliere-Jaricot, S.; Nitschke, R.; Nann, T. Quantum dots versus organic dyes as fluorescent labels. Nat. Methods 2008, 5, 763–775.

    Google Scholar 

  102. Chen, N.; He, Y.; Su, Y. Y.; Li, X. M.; Huang, Q.; Wang, H. F.; Zhang, X. Z.; Tai, R. Z.; Fan, C. H. The cytotoxicity of cadmium-based quantum dots. Biomaterials 2012, 33, 1238–1244.

    Google Scholar 

  103. Polavarapu, L.; Manna, M.; Xu, Q. H. Biocompatible glutathione capped gold clusters as one- and two-photon excitation fluorescence contrast agents for live cells imaging. Nanoscale 2011, 3, 429–434.

    Google Scholar 

  104. Wu, X.; He, X. X.; Wang, K. M.; Xie, C.; Zhou, B.; Qing, Z. H. Ultrasmall near-infrared gold nanoclusters for tumor fluorescence imaging in vivo. Nanoscale 2010, 2, 2244–2249.

    Google Scholar 

  105. Lin, C. A. J.; Yang, T. Y.; Lee, C. H.; Huang, S. H.; Sperling, R. A.; Zanella, M.; Li, J. K.; Shen, J. L.; Wang, H. H.; Yeh, H. I. et al. Synthesis, characterization, and bioconjugation of fluorescent gold nanoclusters toward biological labeling applications. ACS Nano 2009, 3, 395–401.

    Google Scholar 

  106. Koo, H.; Huh, M. S.; Ryu, J. H.; Lee, D. E.; Sun, I. C.; Choi, K.; Kim, K.; Kwon, I. C. Nanoprobes for biomedical imaging in living systems. Nano Today 2011, 6, 204–220.

    Google Scholar 

  107. Michalet, X.; Pinaud, F. F.; Bentolila, L. A.; Tsay, J. M.; Doose, S.; Li, J. J.; Sundaresan, G.; Wu, A. M.; Gambhir, S. S.; Weiss, S. Quantum dots for live cells, in vivo imaging, and diagnostics. Science 2005, 307, 538–544.

    Google Scholar 

  108. Choi, H. S.; Liu, W. H.; Misra, P.; Tanaka, E.; Zimmer, J. P.; Itty Ipe, B.; Bawendi, M. G.; Frangioni, J. V. Renal clearance of quantum dots. Nat. Biotechnol. 2007, 25, 1165–1170.

    Google Scholar 

  109. Zhang, N.; Si, Y. M.; Sun, Z. Z.; Li, S.; Li, S. Y.; Lin, Y. H.; Wang, H. Lab-on-a-drop: Biocompatible fluorescent nanoprobes of gold nanoclusters for label-free evaluation of phosphorylation-induced inhibition of acetylcholinesterase activity towards the ultrasensitive detection of pesticide residues. Analyst 2014, 139, 4620–4628.

    Google Scholar 

  110. Qiao, J.; Mu, X. Y.; Qi, L. J.; Deng, J. Q.; Mao, L. Q. Folic acidfunctionalized fluorescent gold nanoclusters with polymers as linkers for cancer cell imaging. Chem. Commun. 2013, 49, 8030–8032.

    Google Scholar 

  111. Yang, S.; Jiang, Z. Y.; Chen, Z. Z.; Tong, L. L.; Lu, J.; Wang, J. H. Bovine serum albumin-stabilized gold nanoclusters as a fluorescent probe for determination of ferrous ion in cerebrospinal fluids via the Fenton reaction. Microchim. Acta 2015, 182, 1911–1916.

    Google Scholar 

  112. Cao, X. L.; Lian, L. L.; Li, H. W.; Wu, Y. Q.; Lou, D. W. A fluorescence probe based on biomolecule-stabilized gold nanoclusters for the detection of pazufloxacin mesilate. Anal. Sci. 2014, 30, 817–822.

    Google Scholar 

  113. Oh, E.; Fatemi, F. K.; Currie, M.; Delehanty, J. B.; Pons, T.; Fragola, A.; Lévêque-Fort, S.; Goswami, R.; Susumu, K.; Huston, A. L. et al. Pegylated luminescent gold nanoclusters: Synthesis, characterization, bioconjugation, and application to one- and two-photon cellular imaging. Part. Part. Syst. Char. 2013, 30, 453–466.

    Google Scholar 

  114. Jin, L. H.; Shang, L.; Guo, S. J.; Fang, Y. X.; Wen, D.; Wang, L.; Yin, J. Y.; Dong, S. J. Biomolecule-stabilized Au nanoclusters as a fluorescence probe for sensitive detection of glucose. Biosens. Bioelectron. 2011, 26, 1965–1969.

    Google Scholar 

  115. Xia, X. D.; Long, Y. F.; Wang, J. X. Glucose oxidase-functionalized fluorescent gold nanoclusters as probes for glucose. Anal. Chim. Acta 2013, 772, 81–86.

    Google Scholar 

  116. Deng, H. H.; Wu, G. W.; He, D.; Peng, H. P.; Liu, A. L.; Xia, X. H.; Chen, W. Fenton reaction-mediated fluorescence quenching of Nacetyl- L-cysteine-protected gold nanoclusters: Analytical applications of hydrogen peroxide, glucose, and catalase detection. Analyst 2015, 140, 7650–7656.

    Google Scholar 

  117. Guo, S.; Fang, Q. H.; Li, Z. M.; Zhang, J.; Zhang, J. Y.; Li, G. Efficient base-free direct oxidation of glucose to gluconic acid over TiO2-supported gold clusters. Nanoscale 2019, 11, 1326–1334.

    Google Scholar 

  118. Zhu, Y.; Hu, X. C.; Shi, S.; Gao, R. R.; Huang, H. L.; Zhu, Y. Y.; Lv, X. Y.; Yao, T. M. Ultrasensitive and universal fluorescent aptasensor for the detection of biomolecules (ATP, adenosine and thrombin) based on DNA/Ag nanoclusters fluorescence light-up system. Biosens. Bioelectron. 2016, 79, 205–212.

    Google Scholar 

  119. Ma, J. L.; Yin, B. C.; Ye, B. C. A versatile proximity-dependent probe based on light-up DNA-scaffolded silver nanoclusters. Analyst 2016, 141, 1301–1306.

    Google Scholar 

  120. Tao, Y.; Lin, Y. H.; Ren, J. S.; Qu, X. G. A dual fluorometric and colorimetric sensor for dopamine based on BSA-stabilized Au nanoclusters. Biosens. Bioelectron. 2013, 42, 41–46.

    Google Scholar 

  121. Guo, X. R.; Wu, F. Y.; Ni, Y. N.; Kokot, S. Synthesizing a nano-composite of BSA-capped Au nanoclusters/graphitic carbon nitride nanosheets as a new fluorescent probe for dopamine detection. Anal. Chim. Acta 2016, 942, 112–120.

    Google Scholar 

  122. Wang, J.; Chang, Y.; Wu, W. B.; Zhang, P.; Lie, S. Q.; Huang, C. Z. Label-free and selective sensing of uric acid with gold nanoclusters as optical probe. Talanta 2016, 152, 314–320.

    Google Scholar 

  123. Yang, D. Q.; Luo, M. C.; Di, J. W.; Tu, Y. F.; Yan, J. L. Gold nanoclusterbased ratiometric fluorescent probes for hydrogen peroxide and enzymatic sensing of uric acid. Mikrochim. Acta 2018, 185, 305.

    Google Scholar 

  124. Peng, H. P.; Jian, M. L.; Huang, Z. N.; Wang, W. J.; Deng, H. H.; Wu, W. H.; Liu, A. L.; Xia, X. H.; Chen, W. Facile electrochemiluminescence sensing platform based on high-quantum-yield gold nanocluster probe for ultrasensitive glutathione detection. Biosens. Bioelectron. 2018, 105, 71–76.

    Google Scholar 

  125. Zhang, J. R.; Wang, Z. L.; Qu, F.; Luo, H. Q.; Li, N. B. Polyethyleniminecapped silver nanoclusters as a fluorescence probe for highly sensitive detection of folic acid through a two-step electron-transfer process. J. Agric. Food Chem. 2014, 62, 6592–6599.

    Google Scholar 

  126. Chen, Y. L.; Ding, L.; Ju, H. X. In situ tracing of cell surface sialic acid by chemoselective recognition to unload gold nanocluster probe from density tunable dendrimeric array. Chem. Commun. 2013, 49, 862–864.

    Google Scholar 

  127. He, Y.; Wang, X.; Zhu, J. J.; Zhong, S. H.; Song, G. W. Ni2+-modified gold nanoclusters for fluorescence turn-on detection of histidine in biological fluids. Analyst 2012, 137, 4005–4009.

    Google Scholar 

  128. Zhou, Y.; Zhou, T. S.; Zhang, M.; Shi, G. Y. A DNA-scaffolded silver nanocluster/Cu2+ ensemble as a turn-on fluorescent probe for histidine. Analyst 2014, 139, 3122–3126.

    Google Scholar 

  129. Zheng, X. Y.; Yao, T. M.; Zhu, Y.; Shi, S. Cu2+ modulated silver nanoclusters as an on-off-on fluorescence probe for the selective detection of L-histidine. Biosens. Bioelectron. 2015, 66, 103–108.

    Google Scholar 

  130. Liu, T.; Su, Y. Y.; Song, H. J.; Lv, Y. Microwave-assisted green synthesis of ultrasmall fluorescent water-soluble silver nanoclusters and its application in chiral recognition of amino acids. Analyst 2013, 138, 6558–6564.

    Google Scholar 

  131. Zhu, J. J.; Song, X. C.; Gao, L.; Li, Z. M.; Liu, Z.; Ding, S.; Zou, S. B.; He, Y. A highly selective sensor of cysteine with tunable sensitivity and detection window based on dual-emission Ag nanoclusters. Biosens. Bioelectron. 2014, 53, 71–75.

    Google Scholar 

  132. Yu, H.; Liu, Y.; Wang, J. M.; Liang, Q.; Liu, H.; Xu, J.; Shao, S. J. A gold nanocluster-based ratiometric fluorescent probe for cysteine and homocysteine detection in living cells. New J. Chem. 2017, 41, 4416–4423.

    Google Scholar 

  133. Feng, T.; Chen, Y.; Feng, B. B.; Yan, J. L.; Di, J. W. Fluorescence red-shift of gold-silver nanoclusters upon interaction with cysteine and its application. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2019, 206, 97–103.

    Google Scholar 

  134. Zhang, J.; Sajid, M.; Na, N.; Huang, L. Y.; He, D. C.; Ouyang, J. The application of Au nanoclusters in the fluorescence imaging of human serum proteins after native page: Enhancing detection by low-temperature plasma treatment. Biosens. Bioelectron. 2012, 35, 313–318.

    Google Scholar 

  135. Alonso, M. C.; Trapiella-Alfonso, L.; Fernández, J. M. C.; Pereiro, R.; Sanz-Medel, A. Functionalized gold nanoclusters as fluorescent labels for immunoassays: Application to human serum immunoglobulin E determination. Biosens. Bioelectron. 2016, 77, 1055–1061.

    Google Scholar 

  136. Yang, D. Q.; Meng, H. J.; Tu, Y. F.; Yan, J. L. A nanocluster-based fluorescent sensor for sensitive hemoglobin detection. Talanta 2017, 170, 233–237.

    Google Scholar 

  137. Antunes, P.; Watterson, D.; Parmvi, M.; Burger, R.; Boisen, A.; Young, P.; Cooper, M. A.; Hansen, M. F.; Ranzoni, A.; Donolato, M. Quantification of ns1 dengue biomarker in serum via optomagnetic nanocluster detection. Sci. Rep. 2015, 5, 16145.

    Google Scholar 

  138. Quan, H.; Zuo, C. H.; Li, T.; Liu, Y. T.; Li, M. Y.; Zhong, M.; Zhang, Y. Y.; Qi, H. Z.; Yang, M. H. Electrochemical detection of carcinoembryonic antigen based on silver nanocluster/horseradish peroxidase nanocomposite as signal probe. Electrochim. Acta 2015, 176, 893–897.

    Google Scholar 

  139. Li, L. H.; Feng, D. X.; Zhao, J. Q.; Guo, Z. L.; Zhang, Y. Z. Simultaneous fluoroimmunoassay of two tumor markers based on CdTe quantum dots and gold nanocluster coated-silica nanospheres as labels. RSC Adv. 2015, 5, 105992–105998.

    Google Scholar 

  140. Yoshimoto, J.; Sangsuwan, A.; Osaka, I.; Yamashita, K.; Iwasaki, Y.; Inada, M.; Arakawa, R.; Kawasaki, H. Optical properties of 2-methacryloyloxyethyl phosphorylcholine-protected Au4 nanoclusters and their fluorescence sensing of C-reactive protein. J. Phys. Chem. C 2015, 119, 14319–14325.

    Google Scholar 

  141. Song, W.; Wang, Y.; Liang, R. P.; Zhang, L.; Qiu, J. D. Label-free fluorescence assay for protein kinase based on peptide biomineralized gold nanoclusters as signal sensing probe. Biosens. Bioelectron. 2015, 64, 234–240.

    Google Scholar 

  142. Liu, Q.; Na, W. D.; Wang, L.; Su, X. G. Gold nanocluster-based fluorescent assay for label-free detection of protein kinase and its inhibitors. Microchim. Acta. 2017, 184, 3381–3387.

    Google Scholar 

  143. Sun, A. L.; Jia, F. C.; Zhang, Y. F.; Wang, X. N. Gold nanoclusterencapsulated glucoamylase as a biolabel for sensitive detection of thrombin with glucometer readout. Microchim. Acta 2015, 182, 1169–1175.

    Google Scholar 

  144. Wang, L. H.; Ma, K. K.; Zhang, Y. D. Label-free fluorometric detection of S1 nuclease activity by using polycytosine oligonucleotide-templated silver nanoclusters. Anal. Biochem. 2015, 468, 34–38.

    Google Scholar 

  145. Qian, Y. X.; Zhang, Y. D.; Lu, L.; Cai, Y. N. A label-free DNA-templated silver nanocluster probe for fluorescence on-off detection of endonuclease activity and inhibition. Biosens. Bioelectron. 2014, 51, 408–412.

    Google Scholar 

  146. Zhang, Y. D.; Cai, Y. N.; Qi, Z. L.; Lu, L.; Qian, Y. X. DNA-templated silver nanoclusters for fluorescence turn-on assay of acetylcholinesterase activity. Anal. Chem. 2013, 85, 8455–8461.

    Google Scholar 

  147. Liu, R.; Wu, Z. Y.; Yang, Y. L.; Liao, S. Z.; Yu, R. Q. Application of gold–silver nanocluster based fluorescent sensors for determination of acetylcholinesterase activity and its inhibitor. Mater. Res. Express 2018, 5, 065027.

    Google Scholar 

  148. Ma, J. L.; Yin, B. C.; Wu, X.; Ye, B. C. Copper-mediated DNA-scaffolded silver nanocluster on-off switch for detection of pyrophosphate and alkaline phosphatase. Anal. Chem. 2016, 88, 9219–9225.

    Google Scholar 

  149. Liu, W. T.; Lai, H.; Huang, R.; Zhao, C. T.; Wang, Y. M.; Weng, X. C.; Zhou, X. DNA methyltransferase activity detection based on fluorescent silver nanocluster hairpin-shaped DNA probe with 5’-C-rich/g-rich-3’ tails. Biosens. Bioelectron. 2015, 68, 736–740.

    Google Scholar 

  150. Nguyen, P. D.; Cong, V. T.; Baek, C.; Min, J. Fabrication of peptide stabilized fluorescent gold nanocluster/graphene oxide nanocomplex and its application in turn-on detection of metalloproteinase-9. Biosens. Bioelectron. 2017, 89, 666–672.

    Google Scholar 

  151. Hu, L. Z.; Han, S.; Parveen, S.; Yuan, Y. L.; Zhang, L.; Xu, G. B. Highly sensitive fluorescent detection of trypsin based on BSA-stabilized gold nanoclusters. Biosens. Bioelectron. 2012, 32, 297–299.

    Google Scholar 

  152. Zhuo, C. X.; Wang, L. H.; Feng, J. J.; Zhang, Y. D. Label-free fluorescent detection of trypsin activity based on DNA-stabilized silver nanoclusterpeptide conjugates. Sensors 2016, 16, 1477.

    Google Scholar 

  153. Wang, L.; Guo, T.; Lu, Q.; Yan, X. L.; Zhong, D. X.; Zhang, Z. P.; Ni, Y. F.; Han, Y.; Cui, D. X.; Li, X. F. et al. Sea-urchin-like Au nanocluster with surface-enhanced Raman scattering in detecting epidermal growth factor receptor (EGFR) mutation status of malignant pleural effusion. ACS Appl. Mater. Interfaces 2015, 7, 359–369.

    Google Scholar 

  154. Mousavi, M. F.; Mirsian, S.; Noori, A.; Ilkhani, H.; Sarparast, M.; Moradi, N.; Bathaie, S. Z.; Mehrgardi, M. A. BSA-templated Pb nanocluster as a biocompatible signaling probe for electrochemical EGFR immunosensing. Electroanalysis 2017, 29, 861–872.

    Google Scholar 

  155. Wang, G. F.; Zhu, Y. H.; Chen, L.; Zhang, X. J. Photoinduced electron transfer (PET) based label-free aptasensor for platelet-derived growth factor-BB and its logic gate application. Biosens. Bioelectron. 2015, 63, 552–557.

    Google Scholar 

  156. Chen, X.; Baker, G. A. Cholesterol determination using protein-templated fluorescent gold nanocluster probes. Analyst 2013, 138, 7299–7302.

    Google Scholar 

  157. Chang, H. C.; Ho, J. A. Gold nanocluster-assisted fluorescent detection for hydrogen peroxide and cholesterol based on the inner filter effect of gold nanoparticles. Anal. Chem. 2015, 87, 10362–10367.

    Google Scholar 

  158. Hassanzadeh, J.; Khataee, A.; Eskandari, H. Encapsulated cholesterol oxidase in metal-organic framework and biomimetic Ag nanocluster decorated MoS2 nanosheets for sensitive detection of cholesterol. Sens. Actuators. B Chem. 2018, 259, 402–410.

    Google Scholar 

  159. Li, Z. Y.; Wu, Y. T.; Tseng, W. L. UV-light-induced improvement of fluorescence quantum yield of DNA-templated gold nanoclusters: Application to ratiometric fluorescent sensing of nucleic acids. ACS Appl. Mater. Interfaces 2015, 7, 23708–23716.

    Google Scholar 

  160. Zhang, X. X.; Jin, Y.; Li, B. X. Copper nanocluster as a fluorescent indicator for label-free and sensitive detection of DNA hybridization assisted with a cascade isothermal exponential amplification reaction. New J. Chem. 2018, 42, 5178–5184.

    Google Scholar 

  161. Chen, J.; Chen, Q.; Gao, C. J.; Zhang, M. L.; Qin, B.; Qiu, H. D. A SiO2 NP–DNA/silver nanocluster sandwich structure-enhanced fluorescence polarization biosensor for amplified detection of hepatitis B virus DNA. J. Mater. Chem. B 2015, 3, 964–967.

    Google Scholar 

  162. Shah, P.; Choi, S. W.; Kim, H. J.; Cho, S. K.; Thulstrup, P. W.; Bjerrum, M. J.; Bhang, Y. J.; Ahn, J. C.; Yang, S. W. DNA/RNA chimera templates improve the emission intensity and target the accessibility of silver nanocluster-based sensors for human microRNA detection. Analyst 2015, 140, 3422–3430.

    Google Scholar 

  163. Zhang, L. B.; Zhu, J. B.; Zhou, Z. X.; Guo, S. J.; Li, J.; Dong, S. J.; Wang, E. K. A new approach to light up DNA/Ag nanocluster-based beacons for bioanalysis. Chem. Sci. 2013, 4, 4004–4010.

    Google Scholar 

  164. Zhou, W. J.; Zhu, J. B.; Fan, D. Q.; Teng, Y. Q.; Zhu, X. Q.; Dong, S. J. A multicolor chameleon DNA-templated silver nanocluster and its application for ratiometric fluorescence target detection with exponential signal response. Adv. Funct. Mater. 2017, 27, 1704092.

    Google Scholar 

  165. Ge, L.; Sun, X. M.; Hong, Q.; Li, F. Ratiometric nanocluster beacon: A label-free and sensitive fluorescent DNA detection platform. ACS Appl. Mater. Interfaces 2017, 9, 13102–13110.

    Google Scholar 

  166. Yin, J. J.; He, X. X.; Wang, K. M.; Xu, F. Z.; Shangguan, J.; He, D. G.; Shi, H. Label-free and turn-on aptamer strategy for cancer cells detection based on a DNA-silver nanocluster fluorescence upon recognition-induced hybridization. Anal. Chem. 2013, 85, 12011–12019.

    Google Scholar 

  167. Zhu, R.; Luo, X. Y.; Deng, L.; Lei, C. Y.; Huang, Y.; Nie, Z.; Yao, S. Z. An enzymatic polymerization-activated silver nanocluster probe for in situ apoptosis assay. Analyst 2018, 143, 2908–2914.

    Google Scholar 

  168. Cheng, D.; Yu, M. Q.; Fu, F.; Han, W. Y.; Li, G.; Xie, J. P.; Song, Y.; Swihart, M. T.; Song, E. Q. Dual recognition strategy for specific and sensitive detection of bacteria using aptamer-coated magnetic beads and antibiotic-capped gold nanoclusters. Anal. Chem. 2016, 88, 820–825.

    Google Scholar 

  169. Yan, R.; Shou, Z. X.; Chen, J.; Wu, H.; Zhao, Y.; Qiu, L.; Jiang, P. J.; Mou, X. Z.; Wang, J. H.; Li, Y. Q. On–off–on gold nanocluster-based fluorescent probe for rapid Escherichia coli differentiation, detection and bactericide screening. ACS Sustainable Chem. Eng. 2018, 6, 4504–4509.

    Google Scholar 

  170. Lin, X. D.; Liu, Y. Q.; Deng, J. K.; Lyu, Y. L.; Qian, P. C.; Li, Y. F.; Wang, S. Multiple advanced logic gates made of DNA-Ag nanocluster and the application for intelligent detection of pathogenic bacterial genes. Chem. Sci. 2018, 9, 1774–1781.

    Google Scholar 

  171. Sun, S. H.; Ning, X. H.; Zhang, G.; Wang, Y. C.; Peng, C. Q.; Zheng, J. Dimerization of organic dyes on luminescent gold nanoparticles for ratiometric pH sensing. Angew. Chem., Int. Ed. 2016, 55, 2421–2424.

    Google Scholar 

  172. Ding, C. Q.; Tian, Y. Gold nanocluster-based fluorescence biosensor for targeted imaging in cancer cells and ratiometric determination of intracellular pH. Biosens. Bioelectron. 2015, 65, 183–190.

    Google Scholar 

  173. Xiong, H. Y.; Zheng, H. L.; Wang, W.; Liang, J. C.; Wen, W.; Zhang, X. H.; Wang, S. F. A convenient purification method for silver nanoclusters and its applications in fluorescent pH sensors for bacterial monitoring. Biosens. Bioelectron. 2016, 86, 164–168.

    Google Scholar 

  174. Shang, L.; Stockmar, F.; Azadfar, N.; Nienhaus, G. U. Intracellular thermometry by using fluorescent gold nanoclusters. Angew. Chem., Int. Ed. 2013, 52, 11154–11157.

    Google Scholar 

  175. Zhou, W. J.; Zhu, J. B.; Teng, Y.; Du, B. J.; Han, X.; Dong, S. J. Novel dual fluorescence temperature-sensitive chameleon DNA-templated silver nanocluster pair for intracellular thermometry. Nano Res. 2018, 11, 2012–2023.

    Google Scholar 

  176. Wu, Y. T.; Shanmugam, C.; Tseng, W. B.; Hiseh, M. M.; Tseng, W. L. A gold nanocluster-based fluorescent probe for simultaneous pH and temperature sensing and its application to cellular imaging and logic gates. Nanoscale 2016, 8, 11210–11216.

    Google Scholar 

  177. Yang, L. X.; Shang, L.; Nienhaus, G. U. Mechanistic aspects of fluorescent gold nanocluster internalization by live HeLa cells. Nanoscale 2013, 5, 1537–1543.

    Google Scholar 

  178. Wang, X. Y.; Xia, J. H.; Wang, C.; Liu, L.; Zhu, S. X.; Feng, W.; Li, L. D. Preparation of novel fluorescent nanocomposites based on Au nanoclusters and their application in targeted detection of cancer cells. ACS Appl. Mater. Interfaces 2017, 9, 44856–44863.

    Google Scholar 

  179. Nebu, J.; Anjali Devi, J. S.; Aparna, R. S.; Abha, K.; Sony, G. Erlotinib conjugated gold nanocluster enveloped magnetic iron oxide nanoparticles—A targeted probe for imaging pancreatic cancer cells. Sensor. Actuat. B Chem. 2018, 257, 1035–1043.

    Google Scholar 

  180. Bian, P. P.; Zhou, J.; Liu, Y. Y.; Ma, Z. F. One-step fabrication of intense red fluorescent gold nanoclusters and their application in cancer cell imaging. Nanoscale 2013, 5, 6161–6166.

    Google Scholar 

  181. Zhang, W. S.; Lin, D. M.; Wang, H. X.; Li, J. F.; Nienhaus, G. U.; Su, Z. Q.; Wei, G.; Shang, L. Supramolecular self-assembly bioinspired synthesis of luminescent gold nanocluster-embedded peptide nanofibers for temperature sensing and cellular imaging. Bioconjugate Chem. 2017, 28, 2224–2229.

    Google Scholar 

  182. Chattoraj, S.; Bhattacharyya, K. Fluorescent gold nanocluster inside a live breast cell: Etching and higher uptake in cancer cell. J. Phys. Chem. C. 2014, 118, 22339–22346.

    Google Scholar 

  183. Li, J. J.; Zhong, X. Q.; Cheng, F. F.; Zhang, J. R.; Jiang, L. P.; Zhu, J. J. One-pot synthesis of aptamer-functionalized silver nanoclusters for celltype- specific imaging. Anal. Chem. 2012, 84, 4140–4146.

    Google Scholar 

  184. Li, J. J.; You, J.; Dai, Y.; Shi, M. L.; Han, C. P.; Xu, K. Gadolinium oxide nanoparticles and aptamer-functionalized silver nanoclusters-based multimodal molecular imaging nanoprobe for optical/magnetic resonance cancer cell imaging. Anal. Chem. 2014, 86, 11306–11311.

    Google Scholar 

  185. Arora, N.; Gavya, S. L.; Ghosh, S. S. Multi-facet implications of PEGylated lysozyme stabilized-silver nanoclusters loaded recombinant PTEN cargo in cancer theranostics. Biotechnol. Bioeng. 2018, 115, 1116–1127.

    Google Scholar 

  186. Zhang, X. R.; Chen, F. T.; Song, X. J.; He, P.; Zhang, S. S. Proximity ligation detection of lectin Concanavalin A and fluorescence imaging cancer cells using carbohydrate functionalized DNA-silver nanocluster probes. Biosens. Bioelectron. 2018, 104, 27–31.

    Google Scholar 

  187. Jiang, H.; Xu, G.; Sun, Y. M.; Zheng, W. W.; Zhu, X. X.; Wang, B. J.; Zhang, X. J.; Wang, G. F. A “turn-on” silver nanocluster based fluorescent sensor for folate receptor detection and cancer cell imaging under visual analysis. Chem. Commun. 2015, 51, 11810–11813.

    Google Scholar 

  188. Zhu, J. B.; Zhang, L. B.; Teng, Y.; Lou, B. H.; Jia, X. F.; Gu, X. X.; Wang, E. K. G-quadruplex enhanced fluorescence of DNA-silver nanoclusters and their application in bioimaging. Nanoscale 2015, 7, 13224–13229.

    Google Scholar 

  189. Mu, W. Y.; Yang, R.; Robertson, A.; Chen, Q. Y. A near-infrared BSA coated DNA-AgNCs for cellular imaging. Colloid. Surf. B Biointerfaces 2018, 162, 427–431.

    Google Scholar 

  190. Vankayala, R.; Gollavelli, G.; Mandal, B. K. Highly fluorescent and biocompatible iridium nanoclusters for cellular imaging. J. Mater. Sci. Mater. Med. 2013, 24, 1993–2000.

    Google Scholar 

  191. Ge, W.; Zhang, Y. Y.; Ye, J.; Chen, D. H.; Rehman, F. U.; Li, Q. W.; Chen, Y.; Jiang, H.; Wang, X. M. Facile synthesis of fluorescent Au/Ce nanoclusters for high-sensitive bioimaging. J. Nanobiotechnol. 2015, 13, 8.

    Google Scholar 

  192. Chen, H. Y.; Li, B. W.; Wang, C.; Zhang, X.; Cheng, Z. Q.; Dai, X.; Zhu, R.; Gu, Y. Q. Characterization of a fluorescence probe based on gold nanoclusters for cell and animal imaging. Nanotechnology 2013, 24, 055704.

    Google Scholar 

  193. Li, Z.; Peng, H. B.; Liu, J. L.; Tian, Y.; Yang, W. L.; Yao, J. R.; Shao, Z. Z.; Chen, X. Plant protein-directed synthesis of luminescent gold nanocluster hybrids for tumor imaging. ACS Appl. Mater. Interfaces 2018, 10, 83–90.

    Google Scholar 

  194. Liu, J. M.; Chen, J. T.; Yan, X. P. Near infrared fluorescent trypsin stabilized gold nanoclusters as surface Plasmon enhanced energy transfer biosensor and in vivo cancer imaging bioprobe. Anal. Chem. 2013, 85, 3238–3245.

    Google Scholar 

  195. Wu, X. T.; Li, L.; Zhang, L. Y.; Wang, T. T.; Wang, C. G.; Su, Z. M. Multifunctional spherical gold nanocluster aggregate@polyacrylic acid@mesoporous silica nanoparticles for combined cancer dual-modal imaging and chemo-therapy. J. Mater. Chem. B. 2015, 3, 2421–2425.

    Google Scholar 

  196. Nair, L. V.; Nair, R. V.; Shenoy, S. J.; Thekkuveettil, A.; Jayasree, R. S. Blood brain barrier permeable gold nanocluster for targeted brain imaging and therapy: An in vitro and in vivo study. J. Mater. Chem. B. 2017, 5, 8314–8321.

    Google Scholar 

  197. Yu, M. X.; Zhou, J. C.; Du, B. J.; Ning, X. H.; Authement, C.; Gandee, L.; Kapur, P.; Hsieh, J. T.; Zheng, J. Noninvasive staging of kidney dysfunction enabled by renal-clearable luminescent gold nanoparticles. Angew. Chem., Int. Ed. 2016, 55, 2787–2791.

    Google Scholar 

  198. Luo, Z. T.; Zheng, K. Y.; Xie, J. P. Engineering ultrasmall water-soluble gold and silver nanoclusters for biomedical applications. Chem. Commun. 2014, 50, 5143–5155.

    Google Scholar 

  199. Khandelia, R.; Bhandari, S.; Pan, U. N.; Ghosh, S. S.; Chattopadhyay, A. Gold nanocluster embedded albumin nanoparticles for two-photon imaging of cancer cells accompanying drug delivery. Small 2015, 11, 4075–4081.

    Google Scholar 

  200. Goswami, U.; Dutta, A.; Raza, A.; Kandimalla, R.; Kalita, S.; Ghosh, S. S.; Chattopadhyay, A. Transferrin-copper nanocluster-doxorubicin nanoparticles as targeted theranostic cancer nanodrug. ACS Appl. Mater. Interfaces 2018, 10, 3282–3294.

    Google Scholar 

  201. Zhang, X. D.; Wu, F. G.; Liu, P. D.; Wang, H. Y.; Gu, N.; Chen, Z. Synthesis of ultrastable and multifunctional gold nanoclusters with enhanced fluorescence and potential anticancer drug delivery application. J. Colloid Interface Sci. 2015, 455, 6–15.

    Google Scholar 

  202. Zhao, T. T.; Chen, Q. Y.; Yang, H. Spectroscopic study on the formation of DNA-Ag clusters and its application in temperature sensitive vehicles of DOX. Spectrochim. Acta A Mol. Biomol. Spectrosc. 2015, 137, 66–69.

    Google Scholar 

  203. Li, L.; Zhang, L. Y.; Wang, T. T.; Wu, X. T.; Ren, H.; Wang, C. G.; Su, Z. M. Facile and scalable synthesis of novel spherical Au nanocluster assemblies@polyacrylic acid/calcium phosphate nanoparticles for dual-modal imaging-guided cancer chemotherapy. Small 2015, 11, 3162–3173.

    Google Scholar 

  204. Zhou, F. Y.; Feng, B.; Yu, H. J.; Wang, D. G.; Wang, T. T.; Liu, J. P.; Meng, Q. S.; Wang, S. L.; Zhang, P. C.; Zhang, Z. W. et al. Cisplatin prodrug-conjugated gold nanocluster for fluorescence imaging and targeted therapy of the breast cancer. Theranostics 2016, 6, 679–687.

    Google Scholar 

  205. Chatterjee, B.; Ghoshal, A.; Chattopadhyay, A.; Ghosh, S. S. dGTPtemplated luminescent gold nanocluster-based composite nanoparticles for cancer theranostics. ACS Biomater. Sci. Eng. 2018, 4, 1005–1012.

    Google Scholar 

  206. Ghoshal, A.; Goswami, U.; Sahoo, A. K.; Chattopadhyay, A.; Ghosh, S. S. Targeting Wnt canonical signaling by recombinant sFRP1 bound luminescent Au-nanocluster embedded nanoparticles in cancer theranostics. ACS Biomater. Sci. Eng. 2015, 1, 1256–1266.

    Google Scholar 

  207. Chen, H. Y.; Albert, K.; Wen, C. C.; Hsieh, P. Y.; Chen, S. Y.; Huang, N. C.; Lo, S. C.; Chen, J. K.; Hsu, H. Y. Multifunctional silver nanoclusterhybrid oligonucleotide vehicle for cell imaging and microRNA-targeted gene silencing. Colloids Surf. B Biointerfaces 2017, 152, 423–431.

    Google Scholar 

  208. Liu, R.; Xiao, W.; Hu, C.; Xie, R.; Gao, H. L. Theranostic size-reducible and no donor conjugated gold nanocluster fabricated hyaluronic acid nanoparticle with optimal size for combinational treatment of breast cancer and lung metastasis. J. Control. Release 2018, 278, 127–139.

    Google Scholar 

  209. Tao, Y.; Zhang, Y.; Ju, E. G.; Ren, H.; Ren, J. S. Gold nanocluster-based vaccines for dual-delivery of antigens and immunostimulatory oligonucleotides. Nanoscale 2015, 7, 12419–12426.

    Google Scholar 

  210. Li, Q. Z.; Pan, Y. T.; Chen, T. K.; Du, Y. X.; Ge, H. H.; Zhang, B. C.; Xie, J. P.; Yu, H. Z.; Zhu, M. Z. Design and mechanistic study of a novel gold nanocluster-based drug delivery system. Nanoscale 2018, 10, 10166–10172.

    Google Scholar 

  211. Chen, D. H.; Gao, S. P.; Ge, W.; Li, Q. W.; Jiang, H.; Wang, X. M. One-step rapid synthesis of fluorescent platinum nanoclusters for cellular imaging and photothermal treatment. RSC Adv. 2014, 4, 40141–40145.

    Google Scholar 

  212. Zhang, Y. Y.; Li, J. C.; Jiang, H.; Zhao, C. Q.; Wang, X. M. Rapid tumor bioimaging and photothermal treatment based on GSH-capped red fluorescent gold nanoclusters. RSC Adv. 2016, 6, 63331–63337.

    Google Scholar 

  213. Zhang, C. L.; Li, C.; Liu, Y. L.; Zhang, J. P.; Bao, C. C.; Liang, S. J.; Wang, Q.; Yang, Y.; Fu, H. L.; Wang, K. et al. Gold nanoclusters-based nanoprobes for simultaneous fluorescence imaging and targeted photodynamic therapy with superior penetration and retention behavior in tumors. Adv. Funct. Mater. 2015, 25, 1314–1325.

    Google Scholar 

  214. Ai, J.; Li, J.; Ga, L.; Yun, G. H.; Xu, L.; Wang, E. K. Multifunctional near-infrared fluorescent nanoclusters for simultaneous targeted cancer imaging and photodynamic therapy. Sensor. Actuat. B Chem. 2016, 222, 918–922.

    Google Scholar 

  215. Li, H.; Wang, P.; Deng, Y. X.; Zeng, M. Y.; Tang, Y.; Zhu, W. H.; Cheng, Y. S. Combination of active targeting, enzyme-triggered release and fluorescent dye into gold nanoclusters for endomicroscopy-guided photothermal/photodynamic therapy to pancreatic ductal adenocarcinoma. Biomaterials 2017, 139, 30–38.

    Google Scholar 

  216. Kawasaki, H.; Kumar, S.; Li, G.; Zeng, C. J.; Kauffman, D. R.; Yoshimoto, J.; Iwasaki, Y.; Jin, R. C. Generation of singlet oxygen by photoexcited Au25(SR)18 clusters. Chem. Mater. 2014, 26, 2777–2788.

    Google Scholar 

  217. Miyata, S.; Miyaji, H.; Kawasaki, H.; Yamamoto, M.; Nishida, E.; Takita, H.; Akasaka, T.; Ushijima, N.; Iwanaga, T.; Sugaya, T. Antimicrobial photodynamic activity and cytocompatibility of Au25(capt)18 clusters photoexcited by blue LED light irradiation. Int. J. Nanomed. 2017, 12, 2703–2716.

    Google Scholar 

  218. Cifuentes-Rius, A.; Ivask, A.; Das, S.; Penya-Auladell, N.; Fabregas, L.; Fletcher, N. L.; Houston, Z. H.; Thurecht, K. J.; Voelcker, N. H. Gold nanocluster-mediated cellular death under electromagnetic radiation. ACS Appl. Mater. Interfaces 2017, 9, 41159–41167.

    Google Scholar 

  219. Liang, G. H.; Jin, X. D.; Zhang, S. X.; Xing, D. RGD peptide-modified fluorescent gold nanoclusters as highly efficient tumor-targeted radiotherapy sensitizers. Biomaterials 2017, 144, 95–104.

    Google Scholar 

  220. Huang, H. Y.; Cai, K. B.; Chen, P. W.; Lin, C. A. J.; Chang, S. H.; Yuan, C. T. Engineering ligand-metal charge-transfer states in cross-linked gold nanoclusters for greener luminescent solar concentrators with solid-state quantum yields exceeding 50% and low reabsorption losses. J. Phys. Chem. C 2018, 122, 20019–20026.

    Google Scholar 

  221. Soldan, G.; Aljuhani, M. A.; Bootharaju, M. S.; AbdulHalim, L. G.; Parida, M. R.; Emwas, A. H.; Mohammed, O. F.; Bakr, O. M. Gold doping of silver nanoclusters: A 26-fold enhancement in the luminescence quantum yield. Angew. Chem., Int. Ed. 2016, 55, 5749–5753.

    Google Scholar 

  222. Deng, H. H.; Shi, X. Q.; Wang, F. F.; Peng, H. P.; Liu, A. L.; Xia, X. H.; Chen, W. Fabrication of water-soluble, green-emitting gold nanoclusters with a 65% photoluminescence quantum yield via host–guest recognition. Chem. Mater. 2017, 29, 1362–1369.

    Google Scholar 

  223. Naaz, S.; Poddar, S.; Bayen, S. P.; Mondal, M. K.; Roy, D.; Mondal, S. K.; Chowdhury, P.; Saha, S. K. Tenfold enhancement of fluorescence quantum yield of water soluble silver nanoclusters for nano-molar level glucose sensing and precise determination of blood glucose level. Sensor. Actuat. B Chem. 2018, 255, 332–340.

    Google Scholar 

  224. Vinluan III, R. D.; Liu, J. B.; Zhou, C.; Yu, M. X.; Yang, S. Y.; Kumar, A.; Sun, S. S.; Dean, A.; Sun, X. K.; Zheng, J. Glutathione-coated luminescent gold nanoparticles: A surface ligand for minimizing serum protein adsorption. ACS Appl. Mater. Interfaces 2014, 6, 11829–11833.

    Google Scholar 

  225. Vinluan III, R. D.; Yu, M. X.; Gannaway, M.; Sullins, J.; Xu, J.; Zheng, J. Labeling monomeric insulin with renal-clearable luminescent gold nanoparticles. Bioconjugate Chem. 2015, 26, 2435–2441.

    Google Scholar 

  226. Yang, S. Y.; Sun, S. S.; Zhou, C.; Hao, G. Y.; Liu, J. B.; Ramezani, S.; Yu, M. X.; Sun, X. K.; Zheng, J. Renal clearance and degradation of glutathionecoated copper nanoparticles. Bioconjugate Chem. 2015, 26, 511–519.

    Google Scholar 

  227. Zheng, K. Y.; Setyawati, M. I.; Leong, D. T.; Xie, J. P. Surface ligand chemistry of gold nanoclusters determines their antimicrobial ability. Chem. Mater. 2018, 30, 2800–2808.

    Google Scholar 

  228. Zheng, K. Y.; Setyawati, M. I.; Lim, T. P.; Leong, D. T.; Xie, J. P. Antimicrobial cluster bombs: Silver nanoclusters packed with daptomycin. ACS Nano 2016, 10, 7934–7942.

    Google Scholar 

  229. Yang, L.; Yao, C.; Li, F.; Dong, Y. H; Zhang, Z.K.; Yang, D. Y. Synthesis of branched DNA scaffolded super-nanoclusters with enhanced antibacterial performance. Small 2018, 14, 1800185.

    Google Scholar 

  230. Chen, W. Y.; Lin, J. Y.; Chen, W. J.; Luo, L. Y.; Wei-Guang Diau, E.; Chen, Y. C. Functional gold nanoclusters as antimicrobial agents for antibiotic-resistant bacteria. Nanomedicine 2010, 5, 755–764.

    Google Scholar 

  231. Díez, I.; Eronen, P.; Österberg, M.; Linder, M. B.; Ikkala, O.; Ras, R. H. A. Functionalization of nanofibrillated cellulose with silver nanoclusters: Fluorescence and antibacterial activity. Macromol. Biosci. 2011, 11, 1185–1191.

    Google Scholar 

  232. Miao, H.; Zhong, D.; Zhou, Z. N; Yang, X. M. Papain-templated Cu nanoclusters: Assaying and exhibiting dramatic antibacterial activity cooperating with H2O2. Nanoscale 2015, 7, 19066–19072.

    Google Scholar 

Download references

Acknowledgements

Z. K. L. acknowledges the financial support from the National Natural Science Foundation of China (No. 21107083), Zhejiang Public Welfare Technology Research Project (No. LGF19H030014), and Zhejiang Medical and Health Science & Technology Project (No. 2018PY032). R. C. J. acknowledges the support from the AFOSR.

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Rongchao Jin or Zhenkun Lin.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Su, Y., Xue, T., Liu, Y. et al. Luminescent metal nanoclusters for biomedical applications. Nano Res. 12, 1251–1265 (2019). https://doi.org/10.1007/s12274-019-2314-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12274-019-2314-y

Keywords

Navigation