Supra-Amphiphiles for Controlled Self-Assembly and Disassembly - Molecular Self-Assembly: Advances and Applications - page 217

Figure 6.8 Redox-responsive supra-amphiphiles. Reproduced with

permission of Ref. [35]. Copyright 2010, American Chemical
Society.

negative charges, can be hydrolyzed into neutral adenine and single-
charged phosphoric acid upon the treatment of alkaline phosphatase
(e.g., CIAP). Therefore, ATP is a natural multinegatively charged
enzyme-responsive molecule. Using this unique feature, ATP is
complexed with polyglycol-b-polylysine (PEG-b-PLKC) to form a
supra-amphiphile (PEG-b-PLKC-ATP) (Fig. 6.9) [36]. The supra-
amphiphile can self-assemble in water to form spherical aggregates.
Upon the treatment of CIAP, the spherical aggregates will disassemble
and release the loaded guest molecules. The release process can be
finished within 4 h, faster than the conventional enzyme-responsive
systems from amphiphilic polymers. The fast releasing speed could
be attributed to the high enzyme activity of the natural responsive
sites on ATP molecules and the dynamic nature of the electrostatic
interactions. The trend for the development of carrier for drugs will
rely more and more on some important features, including low cost,
high releasing efficiency, good compatibility, and hence forth. It is
anticipated that supra-amphiphiles will be a good candidate in the
areas of drug delivery and nanoreactors.