zwitterion


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Related to zwitterion: isoelectric point

ion

 [i´on]
an atom or group of atoms having a positive (cation) or negative (anion) electric charge by virtue of having gained or lost an electron; substances forming ions are called electrolytes. adj., adj ion´ic.
dipolar ion an ion that has both positive and negative regions of charge.
hydrogen ion the positively charged hydrogen atom (H+), which is the positive ion of all acids. See also hydrogen ion concentration.
hydroxyl ion the negatively charged group, OH, present to excess in alkaline solutions.

zwitterion

/zwit·ter·ion/ (tsvit´er-i″on) an ion that has both positive and negative regions of charge.

zwitterion

[tsvit′ərī′ən]
a molecule that has regions of both negative and positive charge. Amino acids such as glycine are almost always present as zwitterions when in neutral solutions. Also called dipolar ion.
Zwitterionclick for a larger image
Fig. 318 Zwitterion . Molecular structure of (a) undissociated amino acid, (b) Zwitterion.

zwitterion

the chemical form of an AMINO ACID with a dipolar ion state. The pH at which the amino acid exists as a zwitterion is called its ISOELECTRIC POINT and at this pH it will not migrate in an electric field, produced, for example, by ELECTROPHORESIS.

zwitterion

an ion that has both positive and negative regions of charge. Called also dipolar ion.
References in periodicals archive ?
The points representing soil class came further towards the A-line when zwitterion, nonionic and anionic surfactant percentage increased.
Clays modified with zwitterion, nonionic and anionic surfactants gave the lowest contact angles compared to those for natural clay; however, the clays modified with cationic surfactants gave the highest contact angles; and
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.
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.
The properties of the zwitterionic polyurethanes were investigated, and it was found that their thermal stability decreased as the content of zwitterions increased.
Tetracycline-containing zwitterions at pH 7 have good adsorption on soils through cationic and anion exchanges.
The dictionary covers a wider range of terms than parasitology; some virology terms, such as Aino virus, are included, as are some far afield terms, including hundredweight, hydrogen half-cell, and zwitterions.
These "hills" are possibly composed of mostly the salts of carbamate zwitterions or ammonium bicarbonate, which are the reaction products between C[O.
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.