中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Charge on a weak polyelectrolyte

文献类型:期刊论文

作者Wang, Shengqin1,2; Granick, Steve3,4,5; Zhao, Jiang1
刊名JOURNAL OF CHEMICAL PHYSICS
出版日期2008-12-28
卷号129期号:24
关键词Brightness Fluorescence Ionisation Ph Polymer Electrolytes Spectrochemical Analysis
ISSN号0021-9606
DOI10.1063/1.3055596
英文摘要Fluorescence measurements with single-molecule sensitivity are used to measure the hydrodynamic size and local pH of a weak polyelectrolyte, poly-2-vinyl pyridine end labeled with pH-sensitive dye, the polyelectrolyte having concentration so low (nanomolars) that molecular properties are resolvable only from fluorescence experiments and cannot be accessed by light scattering. We find that the local pH near the dye, inferred from its brightness, is consistently three orders of magnitude higher than the bulk pH. Upon varying the bulk pH, we measure the collapse point at which hydrophobic attraction overwhelms electrostatic repulsion between charged elements along the chain, and conclude that adding monovalent salt shifts this coil-to-globule collapse to higher pH than in the absence of salt. The influence of salt appears to shift the ionization equilibrium of this weak polyelectrolyte in the direction of the chain possessing enhanced electric charge at a given pH. Phenomenologically, this is opposite to the case for strong polyelectrolytes, although the mechanism differs.
语种英语
WOS记录号WOS:000262226800002
出版者AMER INST PHYSICS
源URL[http://ir.iccas.ac.cn/handle/121111/64857]  
专题中国科学院化学研究所
通讯作者Zhao, Jiang
作者单位1.Chinese Acad Sci, Inst Chem, Joint Lab Polymer Sci & Mat, Beijing Natl Lab Mol Sci, Beijing 100190, Peoples R China
2.Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China
3.Univ Illinois, Dept Mat Sci, Urbana, IL 61801 USA
4.Univ Illinois, Dept Chem, Urbana, IL 61801 USA
5.Univ Illinois, Dept Phys, Urbana, IL 61801 USA
推荐引用方式
GB/T 7714
Wang, Shengqin,Granick, Steve,Zhao, Jiang. Charge on a weak polyelectrolyte[J]. JOURNAL OF CHEMICAL PHYSICS,2008,129(24).
APA Wang, Shengqin,Granick, Steve,&Zhao, Jiang.(2008).Charge on a weak polyelectrolyte.JOURNAL OF CHEMICAL PHYSICS,129(24).
MLA Wang, Shengqin,et al."Charge on a weak polyelectrolyte".JOURNAL OF CHEMICAL PHYSICS 129.24(2008).

入库方式: OAI收割

来源:化学研究所

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