Poly(ethylene glycol)s in Semidilute Regime [electronic resource] : Radius of Gyration in the Bulk and Partitioning into a Nanopore
- Washington, D.C. : United States. Dept. of Energy. Office of Basic Energy Sciences, 2017.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- pages 2,477-2,483 : digital, PDF file
- Additional Creators:
- Oak Ridge National Laboratory, United States. Department of Energy. Office of Basic Energy Sciences, United States. Department of Energy. Office of Science, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- In this work, using two approaches, small-angle neutron scattering (SANS) from bulk solutions and nanopore conductance-fluctuation analysis, we studied structural and dynamic features of poly(ethylene glycol) (PEG) water/salt solutions in the dilute and semidilute regimes. SANS measurements on PEG 3400 at the zero-average contrast yielded the single chain radius of gyration (Rg) over 1–30 wt %. We observed a small but statistically reliable decrease in Rg with increasing PEG concentration: at 30 wt % the chain contracts by a factor of 0.94. Analyzing conductance fluctuations of the α-hemolysin nanopore in the mixtures of PEG 200 with PEG 3400, we demonstrated that polymer partitioning into the nanopore is mostly due to PEG 200. Specifically, for a 1:1 wt/wt mixture the smaller polymer dominates to the extent that only about 1/25 of the nanopore volume is taken by the larger polymer. In conclusion, these findings advance our conceptual and quantitative understanding of nanopore polymer partitioning; they also support the main assumptions of the recent “polymers-pushing-polymers” model.
- Report Numbers:
- E 1.99:1424464
- Published through SciTech Connect.
Macromolecules 50 6 ISSN 0024-9297 AM
Philip A. Gurnev; Christopher B. Stanley; M. Alphan Aksoyoglu; Kunlun Hong; V. Adrian Parsegian; Sergey M. Bezrukov.
- Funding Information:
View MARC record | catkey: 23497938