Journal of Materials Science

, Volume 53, Issue 14, pp 10013–10024 | Cite as

Interfacial liquid phase-driven removal of copper ions for bioavailable hyperbranched polytriazoles

  • Qingfu Ban
  • Qiang Zhuang
  • Kehe Su
  • Si Wu
  • Jie Kong
Chemical routes to materials


The existence of toxic Cu ions in the products synthesized by Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) click chemistry hinders biomedical applications of these products. Cu ions are difficult to remove because stable Cu(II)–triazole coordination complexes are formed in the CuAAC products. To address this problem, we demonstrate a novel interfacial liquid phase-driven method for the removal of Cu ions. We synthesized small molecules, linear polymers, and hyperbranched polymers by using CuAAC. To remove Cu ions in these products, Cu ions were precipitated using Na2S in a solvent mixture that contains water, dimethylformamide, and dichloromethane (DCM). The products and the CuS precipitates were automatically dispersed in the DCM phase and aqueous phase, respectively, resulting in separation of the products and CuS. Compared to the conventional Cu removal methods, our new method is highly efficient, fast, and generally applicable to small molecules and polymers. More than 98% Cu in the CuAAC products can be removed by using our method. Moreover, we tested the biocompatibility of hyperbranched polymers synthesized using CuAAC and purified using our method. These polymers are compatible to cells, indicating our Cu removal method shows promise in purification of biomaterials synthesized using CuAAC.



The work is supported by the financial support from the National Natural Science Foundation of China (21374089/21703172), the Innovation Foundation for Doctor Dissertation of NPU (CX201706), State Key Laboratory of Solidification Processing in NWPU (SKLSP201629), Shaanxi Natural Science Foundation of Shaanxi Province (2016JQ2013), and Fundamental Research Funds for the Central Universities.

Compliance with ethical standards

Conflict of interest

Authors declare that they have no conflict of interest.

Supplementary material

10853_2018_2292_MOESM1_ESM.doc (26 mb)
Supplementary material 1 (DOC 26624 kb)


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of ScienceNorthwestern Polytechnical UniversityXi’anPeople’s Republic of China
  2. 2.Max Planck Institute for Polymer ResearchMainzGermany

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