Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-12-29
pubmed:abstractText
Cyclic voltammetry and impedance spectroscopy were employed to probe the responsive properties of polyelectrolyte brushes. Poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes over 100 nm thick on gold substrates were synthesized via surface-initiated atom-transfer radical polymerization and quaternized with methane iodide to obtain cationic brushes (Q-PDMAEMA). Q-PDMAEMA brushes respond to electrolytes by exhibiting swollen and collapsed states. Swollen brushes allow good permeability of electroactive probes, while collapsed states block electron transport. Electrolytes have different impacts on the electrochemical properties of Q-PDMAEMA. Some salts (NaNO3) cause brush collapse due to charge screening, while others such as those with more hydrophobic anions (ClO4-, PF6-, and Tf2N-) induce brush collapse because of solubility changes. The collapsed brushes exhibit intrinsically different resistance as probed with impedance. Charged screened brushes retain good permeability to electroactive probes. Strongly coordinating hydrophobic anions lead to insoluble brushes, resulting in a high resistance. These results show that electrochemical impedance spectroscopy is a powerful technique to probe the properties and structure of polyelectrolyte brushes.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Jan
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
176-82
pubmed:year
2007
pubmed:articleTitle
Probing the responsive behavior of polyelectrolyte brushes using electrochemical impedance spectroscopy.
pubmed:affiliation
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China.
pubmed:publicationType
Journal Article