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Related to zwitterion: isoelectric point


 (zwĭt′ər-ī′ən, swĭt′-, tsvĭt′-)
A molecule, especially an amino acid, containing a positively charged ion at one end and a negatively charged ion at the other.

[German : Zwitter, hybrid (from Middle High German zwitarn, from Old High German, from zwi-, twice; see dwo- in Indo-European roots) + Ion, ion (from Greek; see ion).]

zwit′ter·i·on′ic (-ī-ŏn′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Chemistry) chem an ion that carries both a positive and a negative charge
[C20: from German Zwitter hermaphrodite + ion]
zwitterionic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈzwɪt ərˌaɪ ən, ˈswɪt-, ˈtsvɪt-)

an ion with both a positive and a negative charge.
[< German Zwitterion (1897) =Zwitter hybrid, hermaphrodite + Ion ion]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
GLYP and AMPA are considered to exhibit low mobility in soils due to their zwitterion nature and supposed strong sorption to the soil matrix (Sprankle et al., 1975).
The attachment of PEG with [Gd.sub.n.sup.3+]-CNT was performed via a thermal reaction and zwitterion interaction between oxidized CNT carboxylic groups and terminated amines in PEG.
There are three different species of RB molecules depending on the pH of the solution (1) at pH > 4.0 zwitterion [RB.sup.[+ or -]], (2) at pH > (1.0-3.0) [RBH.sup.+], and (3) at pH < 1.0 [RBH.sub.2.sup.2+] [29, 30].
The resulting solid zwitterion was recovered by filtration and washed with ethyl acetate to completely remove the unreacted reactant and then dried at 60[degrees]C under vacuum overnight.
[T.sub.g] of spray-dried trileucine is reliant on pH and can be associated with amount of anion, cation, and zwitterion strength in solution.
Generally, because of the presence of an a-amino acid moiety, a zwitterion contribution is considered.
These functional groups can exist as cation, zwitterion or anion species, depending on the pH of the solution [3].
FQs are the group of chemical compounds called zwitterions. Zwitterion is a neutral molecule with both positive and negative electrical charges on its opposite sides.
The results of previous works reveal that the zwitterion mechanism developed by Caplow [21] and Danckwerts [22] is acceptable for this reaction [11]: