PMID- 18088093
OWN - NLM
STAT- MEDLINE
DCOM- 20080331
LR  - 20181201
IS  - 1526-4602 (Electronic)
IS  - 1525-7797 (Linking)
VI  - 9
IP  - 1
DP  - 2008 Jan
TI  - An acid-labile block copolymer of PDMAEMA and PEG as potential carrier for 
      intelligent gene delivery systems.
PG  - 109-15
AB  - Intelligent gene delivery systems based on physiologically triggered reversible 
      shielding technology have evinced enormous interest due to their potential in 
      vivo applications. In the present work, an acid-labile block copolymer consisting 
      of poly(ethylene glycol) and poly(2-(dimethylamino)ethyl methacrylate) segments 
      connected through a cyclic ortho ester linkage (PEG- a-PDMAEMA) was synthesized 
      by atom transfer radical polymerization of DMAEMA using a PEG macroinitiator with 
      an acid-cleavable end group. PEG- a-PDMAEMA condensed with plasmid DNA formed 
      polyplex nanoparticles with an acid-triggered reversible PEG shield. The 
      pH-dependent shielding/deshielding effect of PEG chains on the polyplex particles 
      were evaluated by zeta potential and size measurements. At pH 7.4, polyplexes 
      generated from PEG- a-PDMAEMA exhibited smaller particle size, lower surface 
      charge, reduced interaction with erythrocytes, and less cytotoxicity compared to 
      PDMAEMA-derived polyplexes. At pH 5.0, zeta potential of polyplexes formed from 
      PEG- a-PDMAEMA increased, leveled up after 2 h of incubation and gradual 
      aggregation occurred in the presence of bovine serum albumin (BSA). In contrast, 
      the stably shielded polyplexes formed by DNA and an acid-stable block copolymer, 
      PEG- b-PDMAEMA, did not change in size and zeta potential in 6 h. In vitro 
      transfection efficiency of the acid-labile copolymer greatly increased after 6 h 
      incubation at pH 5.0, approaching the same level of PDMAEMA, whereas there was 
      only slight increase in efficiency for the stable copolymer, PEG- b-PDMAEMA.
FAU - Lin, Song
AU  - Lin S
AD  - Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer 
      Chemistry and Physics of Ministry of Education, College of Chemistry & Molecular 
      Engineering, Peking University, Beijing 100871, PR China.
FAU - Du, Fusheng
AU  - Du F
FAU - Wang, Yang
AU  - Wang Y
FAU - Ji, Shouping
AU  - Ji S
FAU - Liang, Dehai
AU  - Liang D
FAU - Yu, Lei
AU  - Yu L
FAU - Li, Zichen
AU  - Li Z
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20071219
PL  - United States
TA  - Biomacromolecules
JT  - Biomacromolecules
JID - 100892849
RN  - 0 (Acids)
RN  - 0 (Drug Carriers)
RN  - 0 (Methacrylates)
RN  - 0 (Nylons)
RN  - 0 (poly(2-(dimethylamino)ethyl methacrylate))
RN  - 3WJQ0SDW1A (Polyethylene Glycols)
SB  - IM
MH  - Acids/*chemistry
MH  - Drug Carriers
MH  - Electrophoresis, Agar Gel
MH  - Erythrocytes/drug effects
MH  - Hemolysis
MH  - Humans
MH  - Hydrogen-Ion Concentration
MH  - In Vitro Techniques
MH  - Methacrylates/*chemistry/pharmacology
MH  - Nylons/*chemistry/pharmacology
MH  - Particle Size
MH  - Polyethylene Glycols/*chemistry/pharmacology
MH  - *Transfection
EDAT- 2007/12/20 09:00
MHDA- 2008/04/01 09:00
CRDT- 2007/12/20 09:00
PHST- 2007/12/20 09:00 [pubmed]
PHST- 2008/04/01 09:00 [medline]
PHST- 2007/12/20 09:00 [entrez]
AID - 10.1021/bm7008747 [doi]
PST - ppublish
SO  - Biomacromolecules. 2008 Jan;9(1):109-15. doi: 10.1021/bm7008747. Epub 2007 Dec 
      19.