REVIEW
Probing protein nanopores with poly(ethylene glycol)s
Wenxing Liu,
Ekaterina M. Nestorovich,
Wenxing Liu
Department of Biology, The Catholic University of America, Washington, DC, USA
Search for more papers by this authorCorresponding Author
Ekaterina M. Nestorovich
Department of Biology, The Catholic University of America, Washington, DC, USA
Correspondence
Ekaterina M. Nestorovich, Department of Biology, The Catholic University of America, 620 Michigan Ave, WA DC, 20064, USA.
Email: [email protected]
Search for more papers by this author
Wenxing Liu,
Ekaterina M. Nestorovich,
Wenxing Liu
Department of Biology, The Catholic University of America, Washington, DC, USA
Search for more papers by this authorCorresponding Author
Ekaterina M. Nestorovich
Department of Biology, The Catholic University of America, Washington, DC, USA
Correspondence
Ekaterina M. Nestorovich, Department of Biology, The Catholic University of America, 620 Michigan Ave, WA DC, 20064, USA.
Email: [email protected]
Search for more papers by this authorAbstract
Neutral water-soluble poly(ethylene glycol)s (PEGs) have been extensively explored in protein nanopore research for the past several decades. The principal use of PEGs is to investigate the membrane protein ion channel physical characteristics and transport properties. In addition, protein nanopores are used to study polymer–protein interactions and polymer physicochemical properties. In this review, we focus on the biophysical studies on probing protein ion channels with PEGs, specifically on nanopore sizing by PEG partitioning. We discuss the fluctuation analysis of ion channel currents in response to the PEGs moving within their confined geometries. The advantages, limitations, and recent developments of the approach are also addressed.
CONFLICT OF INTEREST
The authors declare no conflict of interest.
Open Research
DATA AVAILABILITY STATEMENT
Data sharing is not applicable to this review article as no new data were created or analyzed in this study.
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