Y. Ma, B. Chen, N. He, G. Chen, L. W. Li, C. Wu
www.mbs-journal.de
Acknowledgements: Financial support from the National
Natural Scientific Foundation Projects (20934005 and
5
1173177), the Ministry of Science and Technology Key Project
(
(
2012CB933802), and the Hong Kong SAR Earmarked Projects
CUHK4036/11P, 2130281; 2060431 and CUHK7/CRF/12G) is
gratefully acknowledged.
Received: May 24, 2014; Revised: August 17, 2014; Published
online: September 29, 2014; DOI: 10.1002/mabi.201400253
Keywords: degradation; disulfide bonds; gene delivery;
polyethylenimine
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2
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longer lPEI chains slightly more cytotoxic but has nearly
s-s
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ꢁ1
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chainswithasufficientlengthmayincreasetheuptakerate
and protect DNA from degradation. In the current study,
[
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further chain extension via disulfide bonds had nearly no
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initialbranchedbPEI-2kchainswithasimilarmolarmassof
lPEI
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were much smaller, so chain extension greatly affected
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[
[
gene transfection. A combination of our previous and
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plays the dominant role in promoting gene transfection
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Macromol. Biosci. 2014, 14, 1807–1815
ß 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
1814
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