the pH at which a substance is electrically neutral or at which it is at its minimum ionization.
Origin of isoelectric point
First recorded in 1895–1900
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
biochem the pH value at which the net electric charge of a molecule, such as a protein or amino acid, is zero
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The pH at which the electrolyte concentration of an amphoteric substance such as protein is electrically zero because the concentration of its cation form equals the concentration of its anion form.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.