Journal of the American Chemical Society
Article
indicating that larger hydrophobic core area was needed in
order to increase the solubility even with low concentration of
polymer. Following the addition of the block copolymer, the
peak integrals of Saquinavir mesylate increased compared with
DMF standard (Figure 3D), indicating that the solubility of
Saquinavir mesylate could be increased due to the encapsula-
tion behavior of star block copolymer. The solubility of
Saquinavir mesylate increased to 3.0 mM as calculated from the
ratio of the integrated DMF signal with the characteristic peaks
of guest molecule. Followed by a subtraction of the intrinsic
concentration in water, the encapsulated drug concentration
was calculated as 1.1 mM. The maximum loading capacity of
the block copolymer was then determined as 4 by dividing the
mole ratio of drug with the mole ratio of polymer, which means
that each star copolymer can encapsulate up to four Saquinavir
mesylate molecules on average.
ACKNOWLEDGMENTS
■
The authors acknowledge the financial support from the
University of Warwick and China Scholarship Council (Q.Z.).
Some of the equipment used was supported by the Innovative
Uses for Advanced Materials in the Modern World (AM2),
with support from Advantage West Midlands (AWM) and
partially funded by the European Regional Development Fund
(ERDF). D.M.H. is a Royal Society/Wolfson Fellow.
Christopher N. Scanlan has kindly provided the gp120. Royal
Society of Chemistry journal’s Grant for International Authors
Program (G.C.).
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ASSOCIATED CONTENT
■
S
* Supporting Information
Experimental details and supplementary data including NMR,
SEC, UV/vis, FTIR, and MALDI-ToF MS. This material is
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AUTHOR INFORMATION
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Corresponding Authors
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Notes
The authors declare the following competing financial
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dx.doi.org/10.1021/ja4131565 | J. Am. Chem. Soc. 2014, 136, 4325−4332