Macromolecular Research

, Volume 25, Issue 6, pp 599–614 | Cite as

Synthesis and post-polymerisation ligations of PEG-based hyperbranched polymers for RNA conjugation via reversible disulfide linkage

  • Aditya Ardana
  • Andrew K. Whittaker
  • Kristofer J. ThurechtEmail author


The synthesis of architectural polymers with multiple reactive functionalities offers significant promise as platform technologies for development of nano-medicines that require hybrid biomolecule-nanomaterial components. However, there can often be a mismatch in compatibility between the conditions required for the coupling chemistry, while maintaining stability of the biomolecule. This leads to decreased yields and poor functional fidelity. In this report, we describe the synthesis of hyperbranched polymers, where reversible addition fragmentation chaintransfer (RAFT) polymerization is used to control chain molecular weight, end group functionality and the final size of the hyperbranched polymer. Through optimization of the reaction conditions, we demonstrate that branched polymers with controlled size can be synthesized. The subsequent modification of the end-groups within the branched polymer through coupling to small oligonucleotides is then systematically investigated as a function of coupling chemistry. We demonstrate that to achieve the highest degree of coupling, chain extension of the end-group away from the sterically-hindered core of the polymer is required, and that the use of strained alkyne-azide coupling reactions appear to show the highest level of efficiency under the conditions studied. Indeed, when mixed attachment of both fluorescent dye molecules and oligos is attempted under these conditions, almost quantitative end-group modification is achieved. Overall, we highlight the importance of choosing compatible chemistries that allow efficient coupling of biomolecules to synthetic substrates under mild conditions to achieve optimal reaction performance.


polymer-siRNA conjugate hyperbranched polymer reversible addition fragmentation chain transfer bionanomaterial 


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  1. (1).
    A. Ardana, A. K. Whittaker, N. A. J. McMillan, and K. J. Thurecht, J. Chem. Technol. Biotechnol., 90, 1196 (2015).CrossRefGoogle Scholar
  2. (2).
    B. E. Rolfe, I. Blakey, O. Squires, H. Peng, N. R. B. Boase, C. Alexander, P. G. Parsons, G. M. Boyle, A. K. Whittaker, and K. J. Thurecht, J. Am. Chem. Soc., 136, 2413 (2014).CrossRefGoogle Scholar
  3. (3).
    K. J. Thurecht, I. Blakey, H. Peng, O. Squires, S. Hsu, C. Alexander, and A. K. Whittaker, J. Am. Chem. Soc., 132, 5336 (2010).CrossRefGoogle Scholar
  4. (4).
    N. R. B. Boase, I. Blakey, B. E. Rolfe, K. Mardon, and K. J. Thurecht, Polym. Chem., 5, 4450 (2014).CrossRefGoogle Scholar
  5. (5).
    U. Lachelt and E. Wagner, Chem Rev, 115, 11043 (2015).CrossRefGoogle Scholar
  6. (6).
    M. Smet, in Hyperbranched Polymers, John Wiley & Sons, Inc., 2011, pp 387–413.CrossRefGoogle Scholar
  7. (7).
    D. Wang, T. Zhao, X. Zhu, D. Yan, and W. Wang, Chem. Soc. Rev., 44, 4023 (2015).CrossRefGoogle Scholar
  8. (8).
    R. B. Arote, E. S. Lee, H. L. Jiang, Y. K. Kim, Y. J. Choi, M. H. Cho, and C. S. Cho, Bioconjug. Chem., 20, 2231 (2009).CrossRefGoogle Scholar
  9. (9).
    J. V. Jokerst, T. Lobovkina, R. N. Zare, and S. S. Gambhir, Nanomedicine, 6, 715 (2011).CrossRefGoogle Scholar
  10. (10).
    K. Knop, R. Hoogenboom, D. Fischer, and U. S. Schubert, Angew. Chem. Int. Ed. Engl., 49, 6288 (2010).CrossRefGoogle Scholar
  11. (11).
    S. S. Banerjee, N. Aher, R. Patil, and J. Khandare, J. Drug Deliv., 2012, 103973 (2012).CrossRefGoogle Scholar
  12. (12).
    W. R. Gombotz, G. H. Wang, T. A. Horbett, and A. S. Hoffman, J. Biomed. Mater. Res., 25, 1547 (1991).CrossRefGoogle Scholar
  13. (13).
    M. Ogris, S. Brunner, S. Schuller, R. Kircheis, and E. Wagner, Gene Ther., 6, 595 (1999).CrossRefGoogle Scholar
  14. (14).
    R. Haag and F. Kratz, Angew. Chem. Int. Ed. Engl., 45, 1198 (2006).CrossRefGoogle Scholar
  15. (15).
    D. Smith, A. C. Holley, and C. L. McCormick, Polym. Chem., 2, 1428 (2011).CrossRefGoogle Scholar
  16. (16).
    H. Ringsdorf, J. Polym. Sci., Polym. Symp., 51, 135 (2007).CrossRefGoogle Scholar
  17. (17).
    G. Moad, E. Rizzardo, and S. H. Thang, Australian J. Chem., 62, 1402 (2009).CrossRefGoogle Scholar
  18. (18).
    W. A. Braunecker and K. Matyjaszewski, Prog. Polym. Sci., 32, 93 (2007).CrossRefGoogle Scholar
  19. (19).
    K. Matyjaszewski and J. Xia, Chem. Rev., 101, 2921 (2001).CrossRefGoogle Scholar
  20. (20).
    D. A. Shipp, Polym. Rev., 51, 99 (2011).CrossRefGoogle Scholar
  21. (21).
    G. Moad, E. Rizzardo, and S. H. Thang, Australian J. Chem., 65, 985 (2012).CrossRefGoogle Scholar
  22. (22).
    G. Moad, E. Rizzardo, and S. H. Thang, Australian J. Chem., 58, 379 (2005).CrossRefGoogle Scholar
  23. (23).
    A. Gregory and M. H. Stenzel, Prog. Polym. Sci., 37, 38 (2012).CrossRefGoogle Scholar
  24. (24).
    K. Matyjaszewski, Macromolecules, 45, 4015 (2012).CrossRefGoogle Scholar
  25. (25).
    B. Ebeling, Smart Nanohybrids of RAFT Polymers and Inorganic Particles, Springer International Publishing, 2015.CrossRefGoogle Scholar
  26. (26).
    D. J. Keddie, Chem. Soc. Rev., 43, 496 (2014).CrossRefGoogle Scholar
  27. (27).
    Y. K. Chong, T. P. T. Le, G. Moad, E. Rizzardo, and S. H. Thang, Macromolecules, 32, 2071 (1999).CrossRefGoogle Scholar
  28. (28).
    C. L. McCormick and A. B. Lowe, Acc. Chem. Res., 37, 312 (2004).CrossRefGoogle Scholar
  29. (29).
    D. Quemener, T. P. Davis, C. Barner-Kowollik, and M. H. Stenzel, Chem. Commun., 5051 (2006).Google Scholar
  30. (30).
    R. Ranjan and W. J. Brittain, Macromolecules, 40, 6217 (2007).CrossRefGoogle Scholar
  31. (31).
    K. J. Thurecht, I. Blakey, H. Peng, O. Squires, S. Hsu, C. Alexander, and A. K. Whittaker, J. Am. Chem. Soc., 132, 5336 (2010).CrossRefGoogle Scholar
  32. (32).
    D. J. Coles, B. E. Rolfe, N. R. Boase, R. N. Veedu, and K. J. Thurecht, Chem. Commun., 49, 3836 (2013).CrossRefGoogle Scholar
  33. (33).
    G. Saito, J. A. Swanson, and K.-D. Lee, Adv. Drug Deliv. Rev., 55, 199 (2003).CrossRefGoogle Scholar
  34. (34).
    G. T. Hermanson, in Bioconjugate Techniques, 3rd ed., Academic Press, Boston, 2013, pp 229–258.CrossRefGoogle Scholar
  35. (35).
    G. Moad, E. Rizzardo, and S. H. Thang, Polym. Int., 60, 9 (2011).CrossRefGoogle Scholar
  36. (36).
    C. Boyer, V. Bulmus, and T. P. Davis, Macromol. Rapid Commun., 30, 493 (2009).CrossRefGoogle Scholar
  37. (37).
    C. Boyer, J. Liu, V. Bulmus, and T. P. Davis, Australian J. Chem., 62, 830 (2009).CrossRefGoogle Scholar
  38. (38).
    J. Xu, C. Boyer, V. Bulmus, and T. P. Davis, J. Polym. Sci., Part A: Polym. Chem., 47, 4302 (2009).CrossRefGoogle Scholar
  39. (39).
    A. Ardana, A. K. Whittaker, and K. J. Thurecht, Macromolecules, 47, 5211 (2014).CrossRefGoogle Scholar
  40. (40).
    J. Liu, V. Bulmus, C. Barner-Kowollik, M. H. Stenzel, and T. P. Davis, Macromol. Rapid Commun., 28, 305 (2007).CrossRefGoogle Scholar
  41. (41).
    K. L. Heredia, T. H. Nguyen, C. W. Chang, V. Bulmus, T. P. Davis, and H. D. Maynard, Chem. Commun., 3245 (2008).Google Scholar
  42. (42).
    R. Ranjan and W. J. Brittain, Macromol. Rapid Commun., 28, 2084 (2007).CrossRefGoogle Scholar
  43. (43).
    S. Ghosh, S. Basu, and S. Thayumanavan, Macromolecules, 39, 5595 (2006).CrossRefGoogle Scholar
  44. (44).
    J. T. Lai, D. Filla, and R. Shea, Macromolecules, 35, 6754 (2002).CrossRefGoogle Scholar
  45. (45).
    B. Liu, A. Kazlauciunas, J. T. Guthrie, and S. Perrier, Macromolecules, 38, 2131 (2005).CrossRefGoogle Scholar
  46. (46).
    G. Sicilia, A. L. Davis, S. G. Spain, J. P. Magnusson, N. R. B. Boase, K. J. Thurecht, and C. Alexander, Polym. Chem., 7, 2180 (2016).CrossRefGoogle Scholar
  47. (47).
    K. Wang, H. Peng, K. J. Thurecht, S. Puttick, and A. K. Whittaker, Polym. Chem., 5, 1760 (2014).CrossRefGoogle Scholar
  48. (48).
    G. Moad, Macromol. Chem. Phys., 215, 9 (2014).CrossRefGoogle Scholar
  49. (49).
    G. Moad, E. Rizzardo, and S. H. Thang, Acc. Chem. Res., 41, 1133 (2008).CrossRefGoogle Scholar
  50. (50).
    E. Rizzardo, M. Chen, B. Chong, G. Moad, M. Skidmore, and S. H. Thang, Macromol. Symp., 248, 104 (2007).CrossRefGoogle Scholar
  51. (51).
    E. Bicciocchi, Y. K. Chong, L. Giorgini, G. Moad, E. Rizzardo, and S. H. Thang, Macromol. Chem. Phys., 211, 529 (2010).CrossRefGoogle Scholar
  52. (52).
    C. Barner-Kowollik, M. Buback, B. Charleux, M. L. Coote, M. Drache, T. Fukuda, A. Goto, B. Klumperman, A.B. Lowe, J. B. McLeary, G. Moad, M. J. Monteiro, R. D. Sanderson, M. P. Tonge, and P. Vana, J. Polym. Sci., Part A: Polym. Chem., 44, 5809 (2006).CrossRefGoogle Scholar
  53. (53).
    S. Perrier, P. Takolpuckdee, and C. A. Mars, Macromolecules, 38, 2033 (2005).CrossRefGoogle Scholar
  54. (54).
    T. R. Chan, R. Hilgraf, K. B. Sharpless, and V. V. Fokin, Org. Lett., 6, 2853 (2004).CrossRefGoogle Scholar
  55. (55).
    Q. Wang, T. R. Chan, R. Hilgraf, V. V. Fokin, K. B. Sharpless, and M. G. Finn, J. Am. Chem. Soc., 125, 3192 (2003).CrossRefGoogle Scholar
  56. (56).
    D. Giustarini, I. Dalle-Donne, R. Colombo, A. Milzani, and R. Rossi, Nitric Oxide, 19, 252 (2008).CrossRefGoogle Scholar
  57. (57).
    M. F. Debets, S. S. van Berkel, S. Schoffelen, F. P. Rutjes, J. C. van Hest, and F. L. van Delft, Chem. Commun., 46, 97 (2010).CrossRefGoogle Scholar
  58. (58).
    J. Dommerholt, O. van Rooijen, A. Borrmann, C. F. Guerra, F. M. Bickelhaupt, and F. L. van Delft, Nat. Commun., 5, 5378 (2014).CrossRefGoogle Scholar
  59. (59).
    X. Chen, F. Li, and Y. W. Wu, Chem. Commun., 51, 16537 (2015).CrossRefGoogle Scholar
  60. (60).
    M. R. Karver, R. Weissleder, and S. A. Hilderbrand, Angew. Chem. Int. Ed. Engl., 51, 920 (2012).CrossRefGoogle Scholar
  61. (61).
    B. Yameen, M. Ali, M. Álvarez, R. Neumann, W. Ensinger, W. Knoll, and O. Azzaroni, Polym. Chem., 1, 183 (2010).CrossRefGoogle Scholar
  62. (62).
    U. Mansfeld, C. Pietsch, R. Hoogenboom, C. R. Becer, and U. S. Schubert, Polym. Chem., 1, 1560 (2010).CrossRefGoogle Scholar

Copyright information

© The Polymer Society of Korea and Springer Science+Business Media B.V. 2017

Authors and Affiliations

  • Aditya Ardana
    • 1
  • Andrew K. Whittaker
    • 1
    • 2
  • Kristofer J. Thurecht
    • 1
    • 2
    Email author
  1. 1.Australian Institute for Bioengineering and Nanotechnology and Centre for Advanced ImagingThe University of QueenslandSt. LuciaAustralia
  2. 2.ARC Centre of Excellence in Convergent Bio-Nano Science and TechnologyThe University of QueenslandSt. LuciaAustralia

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