Cooperative Entrapment of Xanthene Dyes by a Core-Engineered Unimolecular Micelle

作者：Chen Jian; Lai Yi; Wan Decheng^*; Jin Ming; Pu Hongting

来源：Macromolecular Chemistry and Physics, 2013, 214(16): 1817-1828.

DOI：10.1002/macp.201300221

• cooperativity
• host-guest systems
• molecular recognition
• unimolecular micelles

The cooperative entrapment of a specified guest is only available for a well-defined host. Here it is reported that a common host conducts cooperative entrapment of guests. Alkylation of a hyperbranched polyethylenimine (PEI) by epoxy poly(ethylene glycol) monomethyl ethers (PEG1) leads to a water-soluble PEI@PEG1 (H1). The multifunctional core of H1 is modified to result in H2-H4, with different polarities and ionic charges. H1-H4 exist as unimolecular micelles, and can effectively entrap dyes of rose bengal (RB) or eosin Y (EY). Experiments indicate that the guest dyes are exclusively accommodated in the cores of H1-H4. The encapsulation proceeds in a cooperative manner, as analysis by the Hill equation (n > 1). It is found that the cooperativity stems from the enhanced - stacking of the dyes upon encapsulation, and a polar and ionic environment favors the cooperativity. This is the first example of a cooperative entrapment being realized by a common host.

• 出版日期2013-8-26
• 单位同济大学