zwitterions


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di·po·lar i·ons

ions possessing both a negative charge and a positive charge, each localized at a different point in the molecule, which thus has both positive and negative "poles"; amino acids are the most notable dipolar ions, containing a positively charged NH3+ group and a negatively charged COO- group at neutral pH.
Synonym(s): amphions, zwitterions

di·po·lar ions

(dī-pō'lăr ī'onz)
Ions possessing both a negative charge and a positive charge, each localized at a different point in the molecule, which thus has both positive and negative "poles."
Synonym(s): zwitterions.

zwit·ter hy·poth·e·sis

(tsvit'er hī-poth'ĕ-sis)
That an amphoteric molecule (e.g., an amino acid) has, at its isoelectric point, equal numbers of positive and negative charges, thus becoming a zwitterion (dipolar ion).

zwitterions

The dipolar ions that form from amino acids when they are in solution at a neutral pH.
References in periodicals archive ?
And the second step is the subsequent removal of the proton from the zwitterions by a base, which in case of an amine gives:
Application of the steady-state approximation to the zwitterions [R.
2] with primary and secondary alkanolamines with the zwitterion mechanism.
One was a zwitterion, 3-[4-(p-N,N-didecylaminostyryl 1-pyridinium) propylsulfonate], abbreviated as di-10-ASPPS (Molecular Probes).
a] and critical salt concentration (CSC) values for several zwitterions and their corresponding cyclopolymers.
Using calibration curve, the distance separating the charges of the unknown zwitterions (11 = 1) has been estimated to be 3.
3] spacer separating the zwitterions is reported to be 8.
Three types of hydrophilic groups: cations, anions, and zwitterions, known as "ionogenic groups," are generally employed and form, according to the ionic charges on the polymeric main chain: cationomers (6,7), anionomers (8-11), and zwitterionomers (12), respectively.
ZAPE 7 has dual groups of zwitterion and anion, and it is the anionic portion that dictates the viscosity plot (Fig.